propsals

This reverts commit 871c5ddb4e.

.ai/instructions.md

@@ -51,7 +51,79 @@ This document provides essential context for AI models interacting with this pro
 
 *   **Naming Conventions:**
     *   **Python:** Follows PEP 8. Use clear, descriptive names following snake_case.
-    *   **C++:** Follows the Google C++ Style Guide.
+    *   **C++:** Follows the Google C++ Style Guide with these specifics (following clang-tidy conventions):
+        - Function, method, and variable names: `lower_snake_case`
+        - Class/struct/enum names: `UpperCamelCase`
+        - Top-level constants (global/namespace scope): `UPPER_SNAKE_CASE`
+        - Function-local constants: `lower_snake_case`
+        - Protected/private fields: `lower_snake_case_with_trailing_underscore_`
+        - Favor descriptive names over abbreviations
+
+*   **C++ Field Visibility:**
+    *   **Prefer `protected`:** Use `protected` for most class fields to enable extensibility and testing. Fields should be `lower_snake_case_with_trailing_underscore_`.
+    *   **Use `private` for safety-critical cases:** Use `private` visibility when direct field access could introduce bugs or violate invariants:
+        1. **Pointer lifetime issues:** When setters validate and store pointers from known lists to prevent dangling references.
+           ```cpp
+           // Helper to find matching string in vector and return its pointer
+           inline const char *vector_find(const std::vector<const char *> &vec, const char *value) {
+             for (const char *item : vec) {
+               if (strcmp(item, value) == 0)
+                 return item;
+             }
+             return nullptr;
+           }
+
+           class ClimateDevice {
+            public:
+             void set_custom_fan_modes(std::initializer_list<const char *> modes) {
+               this->custom_fan_modes_ = modes;
+               this->active_custom_fan_mode_ = nullptr;  // Reset when modes change
+             }
+             bool set_custom_fan_mode(const char *mode) {
+               // Find mode in supported list and store that pointer (not the input pointer)
+               const char *validated_mode = vector_find(this->custom_fan_modes_, mode);
+               if (validated_mode != nullptr) {
+                 this->active_custom_fan_mode_ = validated_mode;
+                 return true;
+               }
+               return false;
+             }
+            private:
+             std::vector<const char *> custom_fan_modes_;  // Pointers to string literals in flash
+             const char *active_custom_fan_mode_{nullptr};  // Must point to entry in custom_fan_modes_
+           };
+           ```
+        2. **Invariant coupling:** When multiple fields must remain synchronized to prevent buffer overflows or data corruption.
+           ```cpp
+           class Buffer {
+            public:
+             void resize(size_t new_size) {
+               auto new_data = std::make_unique<uint8_t[]>(new_size);
+               if (this->data_) {
+                 std::memcpy(new_data.get(), this->data_.get(), std::min(this->size_, new_size));
+               }
+               this->data_ = std::move(new_data);
+               this->size_ = new_size;  // Must stay in sync with data_
+             }
+            private:
+             std::unique_ptr<uint8_t[]> data_;
+             size_t size_{0};  // Must match allocated size of data_
+           };
+           ```
+        3. **Resource management:** When setters perform cleanup or registration operations that derived classes might skip.
+    *   **Provide `protected` accessor methods:** When derived classes need controlled access to `private` members.
+
+*   **C++ Preprocessor Directives:**
+    *   **Avoid `#define` for constants:** Using `#define` for constants is discouraged and should be replaced with `const` variables or enums.
+    *   **Use `#define` only for:**
+        - Conditional compilation (`#ifdef`, `#ifndef`)
+        - Compile-time sizes calculated during Python code generation (e.g., configuring `std::array` or `StaticVector` dimensions via `cg.add_define()`)
+
+*   **C++ Additional Conventions:**
+    *   **Member access:** Prefix all class member access with `this->` (e.g., `this->value_` not `value_`)
+    *   **Indentation:** Use spaces (two per indentation level), not tabs
+    *   **Type aliases:** Prefer `using type_t = int;` over `typedef int type_t;`
+    *   **Line length:** Wrap lines at no more than 120 characters
 
 *   **Component Structure:**
     *   **Standard Files:**
@@ -186,6 +258,11 @@ This document provides essential context for AI models interacting with this pro
         └── components/[component]/ # Component-specific tests
         ```
         Run them using `script/test_build_components`. Use `-c <component>` to test specific components and `-t <target>` for specific platforms.
+    *   **Testing All Components Together:** To verify that all components can be tested together without ID conflicts or configuration issues, use:
+        ```bash
+        ./script/test_component_grouping.py -e config --all
+        ```
+        This tests all components in a single build to catch conflicts that might not appear when testing components individually. Use `-e config` for fast configuration validation, or `-e compile` for full compilation testing.
 *   **Debugging and Troubleshooting:**
     *   **Debug Tools:**
         - `esphome config <file>.yaml` to validate configuration.
@@ -216,6 +293,146 @@ This document provides essential context for AI models interacting with this pro
     *   **Component Development:** Keep dependencies minimal, provide clear error messages, and write comprehensive docstrings and tests.
     *   **Code Generation:** Generate minimal and efficient C++ code. Validate all user inputs thoroughly. Support multiple platform variations.
     *   **Configuration Design:** Aim for simplicity with sensible defaults, while allowing for advanced customization.
+    *   **Embedded Systems Optimization:** ESPHome targets resource-constrained microcontrollers. Be mindful of flash size and RAM usage.
+
+        **STL Container Guidelines:**
+
+        ESPHome runs on embedded systems with limited resources. Choose containers carefully:
+
+        1. **Compile-time-known sizes:** Use `std::array` instead of `std::vector` when size is known at compile time.
+           ```cpp
+           // Bad - generates STL realloc code
+           std::vector<int> values;
+
+           // Good - no dynamic allocation
+           std::array<int, MAX_VALUES> values;
+           ```
+           Use `cg.add_define("MAX_VALUES", count)` to set the size from Python configuration.
+
+           **For byte buffers:** Avoid `std::vector<uint8_t>` unless the buffer needs to grow. Use `std::unique_ptr<uint8_t[]>` instead.
+
+           > **Note:** `std::unique_ptr<uint8_t[]>` does **not** provide bounds checking or iterator support like `std::vector<uint8_t>`. Use it only when you do not need these features and want minimal overhead.
+
+           ```cpp
+           // Bad - STL overhead for simple byte buffer
+           std::vector<uint8_t> buffer;
+           buffer.resize(256);
+
+           // Good - minimal overhead, single allocation
+           std::unique_ptr<uint8_t[]> buffer = std::make_unique<uint8_t[]>(256);
+           // Or if size is constant:
+           std::array<uint8_t, 256> buffer;
+           ```
+
+        2. **Compile-time-known fixed sizes with vector-like API:** Use `StaticVector` from `esphome/core/helpers.h` for fixed-size stack allocation with `push_back()` interface.
+           ```cpp
+           // Bad - generates STL realloc code (_M_realloc_insert)
+           std::vector<ServiceRecord> services;
+           services.reserve(5);  // Still includes reallocation machinery
+
+           // Good - compile-time fixed size, stack allocated, no reallocation machinery
+           StaticVector<ServiceRecord, MAX_SERVICES> services;  // Allocates all MAX_SERVICES on stack
+           services.push_back(record1);  // Tracks count but all slots allocated
+           ```
+           Use `cg.add_define("MAX_SERVICES", count)` to set the size from Python configuration.
+           Like `std::array` but with vector-like API (`push_back()`, `size()`) and no STL reallocation code.
+
+        3. **Runtime-known sizes:** Use `FixedVector` from `esphome/core/helpers.h` when the size is only known at runtime initialization.
+           ```cpp
+           // Bad - generates STL realloc code (_M_realloc_insert)
+           std::vector<TxtRecord> txt_records;
+           txt_records.reserve(5);  // Still includes reallocation machinery
+
+           // Good - runtime size, single allocation, no reallocation machinery
+           FixedVector<TxtRecord> txt_records;
+           txt_records.init(record_count);  // Initialize with exact size at runtime
+           ```
+           **Benefits:**
+           - Eliminates `_M_realloc_insert`, `_M_default_append` template instantiations (saves 200-500 bytes per instance)
+           - Single allocation, no upper bound needed
+           - No reallocation overhead
+           - Compatible with protobuf code generation when using `[(fixed_vector) = true]` option
+
+        4. **Small datasets (1-16 elements):** Use `std::vector` or `std::array` with simple structs instead of `std::map`/`std::set`/`std::unordered_map`.
+           ```cpp
+           // Bad - 2KB+ overhead for red-black tree/hash table
+           std::map<std::string, int> small_lookup;
+           std::unordered_map<int, std::string> tiny_map;
+
+           // Good - simple struct with linear search (std::vector is fine)
+           struct LookupEntry {
+             const char *key;
+             int value;
+           };
+           std::vector<LookupEntry> small_lookup = {
+             {"key1", 10},
+             {"key2", 20},
+             {"key3", 30},
+           };
+           // Or std::array if size is compile-time constant:
+           // std::array<LookupEntry, 3> small_lookup = {{ ... }};
+           ```
+           Linear search on small datasets (1-16 elements) is often faster than hashing/tree overhead, but this depends on lookup frequency and access patterns. For frequent lookups in hot code paths, the O(1) vs O(n) complexity difference may still matter even for small datasets. `std::vector` with simple structs is usually fine—it's the heavy containers (`map`, `set`, `unordered_map`) that should be avoided for small datasets unless profiling shows otherwise.
+
+        5. **Detection:** Look for these patterns in compiler output:
+           - Large code sections with STL symbols (vector, map, set)
+           - `alloc`, `realloc`, `dealloc` in symbol names
+           - `_M_realloc_insert`, `_M_default_append` (vector reallocation)
+           - Red-black tree code (`rb_tree`, `_Rb_tree`)
+           - Hash table infrastructure (`unordered_map`, `hash`)
+
+        **When to optimize:**
+        - Core components (API, network, logger)
+        - Widely-used components (mdns, wifi, ble)
+        - Components causing flash size complaints
+
+        **When not to optimize:**
+        - Single-use niche components
+        - Code where readability matters more than bytes
+        - Already using appropriate containers
+
+    *   **State Management:** Use `CORE.data` for component state that needs to persist during configuration generation. Avoid module-level mutable globals.
+
+        **Bad Pattern (Module-Level Globals):**
+        ```python
+        # Don't do this - state persists between compilation runs
+        _component_state = []
+        _use_feature = None
+
+        def enable_feature():
+            global _use_feature
+            _use_feature = True
+        ```
+
+        **Good Pattern (CORE.data with Helpers):**
+        ```python
+        from esphome.core import CORE
+
+        # Keys for CORE.data storage
+        COMPONENT_STATE_KEY = "my_component_state"
+        USE_FEATURE_KEY = "my_component_use_feature"
+
+        def _get_component_state() -> list:
+            """Get component state from CORE.data."""
+            return CORE.data.setdefault(COMPONENT_STATE_KEY, [])
+
+        def _get_use_feature() -> bool | None:
+            """Get feature flag from CORE.data."""
+            return CORE.data.get(USE_FEATURE_KEY)
+
+        def _set_use_feature(value: bool) -> None:
+            """Set feature flag in CORE.data."""
+            CORE.data[USE_FEATURE_KEY] = value
+
+        def enable_feature():
+            _set_use_feature(True)
+        ```
+
+        **Why this matters:**
+        - Module-level globals persist between compilation runs if the dashboard doesn't fork/exec
+        - `CORE.data` automatically clears between runs
+        - Typed helper functions provide better IDE support and maintainability
+        - Encapsulation makes state management explicit and testable
 
 *   **Security:** Be mindful of security when making changes to the API, web server, or any other network-related code. Do not hardcode secrets or keys.
 
@@ -223,3 +440,45 @@ This document provides essential context for AI models interacting with this pro
     *   **Python:** When adding a new Python dependency, add it to the appropriate `requirements*.txt` file and `pyproject.toml`.
     *   **C++ / PlatformIO:** When adding a new C++ dependency, add it to `platformio.ini` and use `cg.add_library`.
     *   **Build Flags:** Use `cg.add_build_flag(...)` to add compiler flags.
+
+## 8. Public API and Breaking Changes
+
+*   **Public C++ API:**
+    *   **Components**: Only documented features at [esphome.io](https://esphome.io) are public API. Undocumented `public` members are internal.
+    *   **Core/Base Classes** (`esphome/core/`, `Component`, `Sensor`, etc.): All `public` members are public API.
+    *   **Components with Global Accessors** (`global_api_server`, etc.): All `public` members are public API (except config setters).
+
+*   **Public Python API:**
+    *   All documented configuration options at [esphome.io](https://esphome.io) are public API.
+    *   Python code in `esphome/core/` actively used by existing core components is considered stable API.
+    *   Other Python code is internal unless explicitly documented for external component use.
+
+*   **Breaking Changes Policy:**
+    *   Aim for **6-month deprecation window** when possible
+    *   Clean breaks allowed for: signature changes, deep refactorings, resource constraints
+    *   Must document migration path in PR description (generates release notes)
+    *   Blog post required for core/base class changes or significant architectural changes
+    *   Full details: https://developers.esphome.io/contributing/code/#public-api-and-breaking-changes
+
+*   **Breaking Change Checklist:**
+    - [ ] Clear justification (RAM/flash savings, architectural improvement)
+    - [ ] Explored non-breaking alternatives
+    - [ ] Added deprecation warnings if possible (use `ESPDEPRECATED` macro for C++)
+    - [ ] Documented migration path in PR description with before/after examples
+    - [ ] Updated all internal usage and esphome-docs
+    - [ ] Tested backward compatibility during deprecation period
+
+*   **Deprecation Pattern (C++):**
+    ```cpp
+    // Remove before 2026.6.0
+    ESPDEPRECATED("Use new_method() instead. Removed in 2026.6.0", "2025.12.0")
+    void old_method() { this->new_method(); }
+    ```
+
+*   **Deprecation Pattern (Python):**
+    ```python
+    # Remove before 2026.6.0
+    if CONF_OLD_KEY in config:
+        _LOGGER.warning(f"'{CONF_OLD_KEY}' deprecated, use '{CONF_NEW_KEY}'. Removed in 2026.6.0")
+        config[CONF_NEW_KEY] = config.pop(CONF_OLD_KEY)  # Auto-migrate
+    ```

.clang-tidy.hash

@@ -1 +1 @@
-499db61c1aa55b98b6629df603a56a1ba7aff5a9a7c781a5c1552a9dcd186c08
+3d46b63015d761c85ca9cb77ab79a389509e5776701fb22aed16e7b79d432c0c

.coveragerc

@@ -1,4 +1,5 @@
 [run]
 omit =
     esphome/components/*
+    esphome/analyze_memory/*
     tests/integration/*

.github/workflows/auto-label-pr.yml

@@ -53,6 +53,7 @@ jobs:
               'new-target-platform',
               'merging-to-release',
               'merging-to-beta',
+              'chained-pr',
               'core',
               'small-pr',
               'dashboard',
@@ -140,6 +141,8 @@ jobs:
                 labels.add('merging-to-release');
               } else if (baseRef === 'beta') {
                 labels.add('merging-to-beta');
+              } else if (baseRef !== 'dev') {
+                labels.add('chained-pr');
               }
 
               return labels;
@@ -413,7 +416,7 @@ jobs:
             }
 
             // Generate review messages
-            function generateReviewMessages(finalLabels) {
+            function generateReviewMessages(finalLabels, originalLabelCount) {
               const messages = [];
               const prAuthor = context.payload.pull_request.user.login;
 
@@ -427,15 +430,15 @@ jobs:
                   .reduce((sum, file) => sum + (file.deletions || 0), 0);
                 const nonTestChanges = (totalAdditions - testAdditions) - (totalDeletions - testDeletions);
 
-                const tooManyLabels = finalLabels.length > MAX_LABELS;
+                const tooManyLabels = originalLabelCount > MAX_LABELS;
                 const tooManyChanges = nonTestChanges > TOO_BIG_THRESHOLD;
 
                 let message = `${TOO_BIG_MARKER}\n### 📦 Pull Request Size\n\n`;
 
                 if (tooManyLabels && tooManyChanges) {
-                  message += `This PR is too large with ${nonTestChanges} line changes (excluding tests) and affects ${finalLabels.length} different components/areas.`;
+                  message += `This PR is too large with ${nonTestChanges} line changes (excluding tests) and affects ${originalLabelCount} different components/areas.`;
                 } else if (tooManyLabels) {
-                  message += `This PR affects ${finalLabels.length} different components/areas.`;
+                  message += `This PR affects ${originalLabelCount} different components/areas.`;
                 } else {
                   message += `This PR is too large with ${nonTestChanges} line changes (excluding tests).`;
                 }
@@ -463,8 +466,8 @@ jobs:
             }
 
             // Handle reviews
-            async function handleReviews(finalLabels) {
-              const reviewMessages = generateReviewMessages(finalLabels);
+            async function handleReviews(finalLabels, originalLabelCount) {
+              const reviewMessages = generateReviewMessages(finalLabels, originalLabelCount);
               const hasReviewableLabels = finalLabels.some(label =>
                 ['too-big', 'needs-codeowners'].includes(label)
               );
@@ -528,8 +531,8 @@ jobs:
             const apiData = await fetchApiData();
             const baseRef = context.payload.pull_request.base.ref;
 
-            // Early exit for non-dev branches
-            if (baseRef !== 'dev') {
+            // Early exit for release and beta branches only
+            if (baseRef === 'release' || baseRef === 'beta') {
               const branchLabels = await detectMergeBranch();
               const finalLabels = Array.from(branchLabels);
 
@@ -624,6 +627,7 @@ jobs:
 
             // Handle too many labels (only for non-mega PRs)
             const tooManyLabels = finalLabels.length > MAX_LABELS;
+            const originalLabelCount = finalLabels.length;
 
             if (tooManyLabels && !isMegaPR && !finalLabels.includes('too-big')) {
               finalLabels = ['too-big'];
@@ -632,7 +636,7 @@ jobs:
             console.log('Computed labels:', finalLabels.join(', '));
 
             // Handle reviews
-            await handleReviews(finalLabels);
+            await handleReviews(finalLabels, originalLabelCount);
 
             // Apply labels
             if (finalLabels.length > 0) {

.github/workflows/ci-api-proto.yml

@@ -62,7 +62,7 @@ jobs:
         run: git diff
       - if: failure()
         name: Archive artifacts
-        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
         with:
           name: generated-proto-files
           path: |

.github/workflows/ci-clang-tidy-hash.yml

@@ -6,6 +6,7 @@ on:
       - ".clang-tidy"
       - "platformio.ini"
       - "requirements_dev.txt"
+      - "sdkconfig.defaults"
       - ".clang-tidy.hash"
       - "script/clang_tidy_hash.py"
       - ".github/workflows/ci-clang-tidy-hash.yml"

.github/workflows/ci-memory-impact-comment.yml

@@ -0,0 +1,111 @@
+---
+name: Memory Impact Comment (Forks)
+
+on:
+  workflow_run:
+    workflows: ["CI"]
+    types: [completed]
+
+permissions:
+  contents: read
+  pull-requests: write
+  actions: read
+
+jobs:
+  memory-impact-comment:
+    name: Post memory impact comment (fork PRs only)
+    runs-on: ubuntu-24.04
+    # Only run for PRs from forks that had successful CI runs
+    if: >
+      github.event.workflow_run.event == 'pull_request' &&
+      github.event.workflow_run.conclusion == 'success' &&
+      github.event.workflow_run.head_repository.full_name != github.repository
+    env:
+      GH_TOKEN: ${{ github.token }}
+    steps:
+      - name: Get PR details
+        id: pr
+        run: |
+          # Get PR details by searching for PR with matching head SHA
+          # The workflow_run.pull_requests field is often empty for forks
+          # Use paginate to handle repos with many open PRs
+          head_sha="${{ github.event.workflow_run.head_sha }}"
+          pr_data=$(gh api --paginate "/repos/${{ github.repository }}/pulls" \
+            --jq ".[] | select(.head.sha == \"$head_sha\") | {number: .number, base_ref: .base.ref}" \
+            | head -n 1)
+
+          if [ -z "$pr_data" ]; then
+            echo "No PR found for SHA $head_sha, skipping"
+            echo "skip=true" >> "$GITHUB_OUTPUT"
+            exit 0
+          fi
+
+          pr_number=$(echo "$pr_data" | jq -r '.number')
+          base_ref=$(echo "$pr_data" | jq -r '.base_ref')
+
+          echo "pr_number=$pr_number" >> "$GITHUB_OUTPUT"
+          echo "base_ref=$base_ref" >> "$GITHUB_OUTPUT"
+          echo "Found PR #$pr_number targeting base branch: $base_ref"
+
+      - name: Check out code from base repository
+        if: steps.pr.outputs.skip != 'true'
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          # Always check out from the base repository (esphome/esphome), never from forks
+          # Use the PR's target branch to ensure we run trusted code from the main repo
+          repository: ${{ github.repository }}
+          ref: ${{ steps.pr.outputs.base_ref }}
+
+      - name: Restore Python
+        if: steps.pr.outputs.skip != 'true'
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: "3.11"
+          cache-key: ${{ hashFiles('.cache-key') }}
+
+      - name: Download memory analysis artifacts
+        if: steps.pr.outputs.skip != 'true'
+        run: |
+          run_id="${{ github.event.workflow_run.id }}"
+          echo "Downloading artifacts from workflow run $run_id"
+
+          mkdir -p memory-analysis
+
+          # Download target analysis artifact
+          if gh run download --name "memory-analysis-target" --dir memory-analysis --repo "${{ github.repository }}" "$run_id"; then
+            echo "Downloaded memory-analysis-target artifact."
+          else
+            echo "No memory-analysis-target artifact found."
+          fi
+
+          # Download PR analysis artifact
+          if gh run download --name "memory-analysis-pr" --dir memory-analysis --repo "${{ github.repository }}" "$run_id"; then
+            echo "Downloaded memory-analysis-pr artifact."
+          else
+            echo "No memory-analysis-pr artifact found."
+          fi
+
+      - name: Check if artifacts exist
+        id: check
+        if: steps.pr.outputs.skip != 'true'
+        run: |
+          if [ -f ./memory-analysis/memory-analysis-target.json ] && [ -f ./memory-analysis/memory-analysis-pr.json ]; then
+            echo "found=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "found=false" >> "$GITHUB_OUTPUT"
+            echo "Memory analysis artifacts not found, skipping comment"
+          fi
+
+      - name: Post or update PR comment
+        if: steps.pr.outputs.skip != 'true' && steps.check.outputs.found == 'true'
+        env:
+          PR_NUMBER: ${{ steps.pr.outputs.pr_number }}
+        run: |
+          . venv/bin/activate
+          # Pass PR number and JSON file paths directly to Python script
+          # Let Python parse the JSON to avoid shell injection risks
+          # The script will validate and sanitize all inputs
+          python script/ci_memory_impact_comment.py \
+            --pr-number "$PR_NUMBER" \
+            --target-json ./memory-analysis/memory-analysis-target.json \
+            --pr-json ./memory-analysis/memory-analysis-pr.json

.github/workflows/ci.yml

@@ -114,7 +114,6 @@ jobs:
       matrix:
         python-version:
           - "3.11"
-          - "3.12"
           - "3.13"
         os:
           - ubuntu-latest
@@ -126,12 +125,8 @@ jobs:
           # version used for docker images on Windows and macOS
           - python-version: "3.13"
             os: windows-latest
-          - python-version: "3.12"
-            os: windows-latest
           - python-version: "3.13"
             os: macOS-latest
-          - python-version: "3.12"
-            os: macOS-latest
     runs-on: ${{ matrix.os }}
     needs:
       - common
@@ -175,9 +170,17 @@ jobs:
     outputs:
       integration-tests: ${{ steps.determine.outputs.integration-tests }}
       clang-tidy: ${{ steps.determine.outputs.clang-tidy }}
+      clang-tidy-mode: ${{ steps.determine.outputs.clang-tidy-mode }}
       python-linters: ${{ steps.determine.outputs.python-linters }}
       changed-components: ${{ steps.determine.outputs.changed-components }}
+      changed-components-with-tests: ${{ steps.determine.outputs.changed-components-with-tests }}
+      directly-changed-components-with-tests: ${{ steps.determine.outputs.directly-changed-components-with-tests }}
       component-test-count: ${{ steps.determine.outputs.component-test-count }}
+      changed-cpp-file-count: ${{ steps.determine.outputs.changed-cpp-file-count }}
+      memory_impact: ${{ steps.determine.outputs.memory-impact }}
+      cpp-unit-tests-run-all: ${{ steps.determine.outputs.cpp-unit-tests-run-all }}
+      cpp-unit-tests-components: ${{ steps.determine.outputs.cpp-unit-tests-components }}
+      component-test-batches: ${{ steps.determine.outputs.component-test-batches }}
     steps:
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
@@ -189,6 +192,11 @@ jobs:
         with:
           python-version: ${{ env.DEFAULT_PYTHON }}
           cache-key: ${{ needs.common.outputs.cache-key }}
+      - name: Restore components graph cache
+        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: .temp/components_graph.json
+          key: components-graph-${{ hashFiles('esphome/components/**/*.py') }}
       - name: Determine which tests to run
         id: determine
         env:
@@ -202,9 +210,23 @@ jobs:
           # Extract individual fields
           echo "integration-tests=$(echo "$output" | jq -r '.integration_tests')" >> $GITHUB_OUTPUT
           echo "clang-tidy=$(echo "$output" | jq -r '.clang_tidy')" >> $GITHUB_OUTPUT
+          echo "clang-tidy-mode=$(echo "$output" | jq -r '.clang_tidy_mode')" >> $GITHUB_OUTPUT
           echo "python-linters=$(echo "$output" | jq -r '.python_linters')" >> $GITHUB_OUTPUT
           echo "changed-components=$(echo "$output" | jq -c '.changed_components')" >> $GITHUB_OUTPUT
+          echo "changed-components-with-tests=$(echo "$output" | jq -c '.changed_components_with_tests')" >> $GITHUB_OUTPUT
+          echo "directly-changed-components-with-tests=$(echo "$output" | jq -c '.directly_changed_components_with_tests')" >> $GITHUB_OUTPUT
           echo "component-test-count=$(echo "$output" | jq -r '.component_test_count')" >> $GITHUB_OUTPUT
+          echo "changed-cpp-file-count=$(echo "$output" | jq -r '.changed_cpp_file_count')" >> $GITHUB_OUTPUT
+          echo "memory-impact=$(echo "$output" | jq -c '.memory_impact')" >> $GITHUB_OUTPUT
+          echo "cpp-unit-tests-run-all=$(echo "$output" | jq -r '.cpp_unit_tests_run_all')" >> $GITHUB_OUTPUT
+          echo "cpp-unit-tests-components=$(echo "$output" | jq -c '.cpp_unit_tests_components')" >> $GITHUB_OUTPUT
+          echo "component-test-batches=$(echo "$output" | jq -c '.component_test_batches')" >> $GITHUB_OUTPUT
+      - name: Save components graph cache
+        if: github.ref == 'refs/heads/dev'
+        uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: .temp/components_graph.json
+          key: components-graph-${{ hashFiles('esphome/components/**/*.py') }}
 
   integration-tests:
     name: Run integration tests
@@ -242,7 +264,34 @@ jobs:
           . venv/bin/activate
           pytest -vv --no-cov --tb=native -n auto tests/integration/
 
-  clang-tidy:
+  cpp-unit-tests:
+    name: Run C++ unit tests
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: github.event_name == 'pull_request' && (needs.determine-jobs.outputs.cpp-unit-tests-run-all == 'true' || needs.determine-jobs.outputs.cpp-unit-tests-components != '[]')
+    steps:
+      - name: Check out code from GitHub
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+
+      - name: Run cpp_unit_test.py
+        run: |
+          . venv/bin/activate
+          if [ "${{ needs.determine-jobs.outputs.cpp-unit-tests-run-all }}" = "true" ]; then
+            script/cpp_unit_test.py --all
+          else
+            ARGS=$(echo '${{ needs.determine-jobs.outputs.cpp-unit-tests-components }}' | jq -r '.[] | @sh' | xargs)
+            script/cpp_unit_test.py $ARGS
+          fi
+
+  clang-tidy-single:
     name: ${{ matrix.name }}
     runs-on: ubuntu-24.04
     needs:
@@ -260,22 +309,6 @@ jobs:
             name: Run script/clang-tidy for ESP8266
             options: --environment esp8266-arduino-tidy --grep USE_ESP8266
             pio_cache_key: tidyesp8266
-          - id: clang-tidy
-            name: Run script/clang-tidy for ESP32 Arduino 1/4
-            options: --environment esp32-arduino-tidy --split-num 4 --split-at 1
-            pio_cache_key: tidyesp32
-          - id: clang-tidy
-            name: Run script/clang-tidy for ESP32 Arduino 2/4
-            options: --environment esp32-arduino-tidy --split-num 4 --split-at 2
-            pio_cache_key: tidyesp32
-          - id: clang-tidy
-            name: Run script/clang-tidy for ESP32 Arduino 3/4
-            options: --environment esp32-arduino-tidy --split-num 4 --split-at 3
-            pio_cache_key: tidyesp32
-          - id: clang-tidy
-            name: Run script/clang-tidy for ESP32 Arduino 4/4
-            options: --environment esp32-arduino-tidy --split-num 4 --split-at 4
-            pio_cache_key: tidyesp32
           - id: clang-tidy
             name: Run script/clang-tidy for ESP32 IDF
             options: --environment esp32-idf-tidy --grep USE_ESP_IDF
@@ -356,79 +389,192 @@ jobs:
         # yamllint disable-line rule:line-length
         if: always()
 
-  test-build-components:
-    name: Component test ${{ matrix.file }}
+  clang-tidy-nosplit:
+    name: Run script/clang-tidy for ESP32 Arduino
     runs-on: ubuntu-24.04
     needs:
       - common
       - determine-jobs
-    if: github.event_name == 'pull_request' && fromJSON(needs.determine-jobs.outputs.component-test-count) > 0 && fromJSON(needs.determine-jobs.outputs.component-test-count) < 100
+    if: needs.determine-jobs.outputs.clang-tidy-mode == 'nosplit'
+    env:
+      GH_TOKEN: ${{ github.token }}
+    steps:
+      - name: Check out code from GitHub
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          # Need history for HEAD~1 to work for checking changed files
+          fetch-depth: 2
+
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+
+      - name: Cache platformio
+        if: github.ref == 'refs/heads/dev'
+        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: ~/.platformio
+          key: platformio-tidyesp32-${{ hashFiles('platformio.ini') }}
+
+      - name: Cache platformio
+        if: github.ref != 'refs/heads/dev'
+        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: ~/.platformio
+          key: platformio-tidyesp32-${{ hashFiles('platformio.ini') }}
+
+      - name: Register problem matchers
+        run: |
+          echo "::add-matcher::.github/workflows/matchers/gcc.json"
+          echo "::add-matcher::.github/workflows/matchers/clang-tidy.json"
+
+      - name: Check if full clang-tidy scan needed
+        id: check_full_scan
+        run: |
+          . venv/bin/activate
+          if python script/clang_tidy_hash.py --check; then
+            echo "full_scan=true" >> $GITHUB_OUTPUT
+            echo "reason=hash_changed" >> $GITHUB_OUTPUT
+          else
+            echo "full_scan=false" >> $GITHUB_OUTPUT
+            echo "reason=normal" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Run clang-tidy
+        run: |
+          . venv/bin/activate
+          if [ "${{ steps.check_full_scan.outputs.full_scan }}" = "true" ]; then
+            echo "Running FULL clang-tidy scan (hash changed)"
+            script/clang-tidy --all-headers --fix --environment esp32-arduino-tidy
+          else
+            echo "Running clang-tidy on changed files only"
+            script/clang-tidy --all-headers --fix --changed --environment esp32-arduino-tidy
+          fi
+        env:
+          # Also cache libdeps, store them in a ~/.platformio subfolder
+          PLATFORMIO_LIBDEPS_DIR: ~/.platformio/libdeps
+
+      - name: Suggested changes
+        run: script/ci-suggest-changes
+        if: always()
+
+  clang-tidy-split:
+    name: ${{ matrix.name }}
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: needs.determine-jobs.outputs.clang-tidy-mode == 'split'
+    env:
+      GH_TOKEN: ${{ github.token }}
     strategy:
       fail-fast: false
       max-parallel: 2
       matrix:
-        file: ${{ fromJson(needs.determine-jobs.outputs.changed-components) }}
-    steps:
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install libsdl2-dev
+        include:
+          - id: clang-tidy
+            name: Run script/clang-tidy for ESP32 Arduino 1/4
+            options: --environment esp32-arduino-tidy --split-num 4 --split-at 1
+          - id: clang-tidy
+            name: Run script/clang-tidy for ESP32 Arduino 2/4
+            options: --environment esp32-arduino-tidy --split-num 4 --split-at 2
+          - id: clang-tidy
+            name: Run script/clang-tidy for ESP32 Arduino 3/4
+            options: --environment esp32-arduino-tidy --split-num 4 --split-at 3
+          - id: clang-tidy
+            name: Run script/clang-tidy for ESP32 Arduino 4/4
+            options: --environment esp32-arduino-tidy --split-num 4 --split-at 4
 
+    steps:
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          # Need history for HEAD~1 to work for checking changed files
+          fetch-depth: 2
+
       - name: Restore Python
         uses: ./.github/actions/restore-python
         with:
           python-version: ${{ env.DEFAULT_PYTHON }}
           cache-key: ${{ needs.common.outputs.cache-key }}
-      - name: test_build_components -e config -c ${{ matrix.file }}
-        run: |
-          . venv/bin/activate
-          ./script/test_build_components -e config -c ${{ matrix.file }}
-      - name: test_build_components -e compile -c ${{ matrix.file }}
-        run: |
-          . venv/bin/activate
-          ./script/test_build_components -e compile -c ${{ matrix.file }}
 
-  test-build-components-splitter:
-    name: Split components for testing into 20 groups maximum
-    runs-on: ubuntu-24.04
-    needs:
-      - common
-      - determine-jobs
-    if: github.event_name == 'pull_request' && fromJSON(needs.determine-jobs.outputs.component-test-count) >= 100
-    outputs:
-      matrix: ${{ steps.split.outputs.components }}
-    steps:
-      - name: Check out code from GitHub
-        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
-      - name: Split components into 20 groups
-        id: split
+      - name: Cache platformio
+        if: github.ref == 'refs/heads/dev'
+        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: ~/.platformio
+          key: platformio-tidyesp32-${{ hashFiles('platformio.ini') }}
+
+      - name: Cache platformio
+        if: github.ref != 'refs/heads/dev'
+        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: ~/.platformio
+          key: platformio-tidyesp32-${{ hashFiles('platformio.ini') }}
+
+      - name: Register problem matchers
         run: |
-          components=$(echo '${{ needs.determine-jobs.outputs.changed-components }}' | jq -c '.[]' | shuf | jq -s -c '[_nwise(20) | join(" ")]')
-          echo "components=$components" >> $GITHUB_OUTPUT
+          echo "::add-matcher::.github/workflows/matchers/gcc.json"
+          echo "::add-matcher::.github/workflows/matchers/clang-tidy.json"
+
+      - name: Check if full clang-tidy scan needed
+        id: check_full_scan
+        run: |
+          . venv/bin/activate
+          if python script/clang_tidy_hash.py --check; then
+            echo "full_scan=true" >> $GITHUB_OUTPUT
+            echo "reason=hash_changed" >> $GITHUB_OUTPUT
+          else
+            echo "full_scan=false" >> $GITHUB_OUTPUT
+            echo "reason=normal" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Run clang-tidy
+        run: |
+          . venv/bin/activate
+          if [ "${{ steps.check_full_scan.outputs.full_scan }}" = "true" ]; then
+            echo "Running FULL clang-tidy scan (hash changed)"
+            script/clang-tidy --all-headers --fix ${{ matrix.options }}
+          else
+            echo "Running clang-tidy on changed files only"
+            script/clang-tidy --all-headers --fix --changed ${{ matrix.options }}
+          fi
+        env:
+          # Also cache libdeps, store them in a ~/.platformio subfolder
+          PLATFORMIO_LIBDEPS_DIR: ~/.platformio/libdeps
+
+      - name: Suggested changes
+        run: script/ci-suggest-changes
+        if: always()
 
   test-build-components-split:
-    name: Test split components
+    name: Test components batch (${{ matrix.components }})
     runs-on: ubuntu-24.04
     needs:
       - common
       - determine-jobs
-      - test-build-components-splitter
-    if: github.event_name == 'pull_request' && fromJSON(needs.determine-jobs.outputs.component-test-count) >= 100
+    if: github.event_name == 'pull_request' && fromJSON(needs.determine-jobs.outputs.component-test-count) > 0
     strategy:
       fail-fast: false
-      max-parallel: 4
+      max-parallel: ${{ (startsWith(github.base_ref, 'beta') || startsWith(github.base_ref, 'release')) && 8 || 4 }}
       matrix:
-        components: ${{ fromJson(needs.test-build-components-splitter.outputs.matrix) }}
+        components: ${{ fromJson(needs.determine-jobs.outputs.component-test-batches) }}
     steps:
+      - name: Show disk space
+        run: |
+          echo "Available disk space:"
+          df -h
+
       - name: List components
         run: echo ${{ matrix.components }}
 
-      - name: Install dependencies
-        run: |
-          sudo apt-get update
-          sudo apt-get install libsdl2-dev
+      - name: Cache apt packages
+        uses: awalsh128/cache-apt-pkgs-action@acb598e5ddbc6f68a970c5da0688d2f3a9f04d05 # v1.5.3
+        with:
+          packages: libsdl2-dev
+          version: 1.0
 
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
@@ -437,27 +583,83 @@ jobs:
         with:
           python-version: ${{ env.DEFAULT_PYTHON }}
           cache-key: ${{ needs.common.outputs.cache-key }}
-      - name: Validate config
+      - name: Validate and compile components with intelligent grouping
         run: |
           . venv/bin/activate
-          for component in ${{ matrix.components }}; do
-            ./script/test_build_components -e config -c $component
-          done
-      - name: Compile config
-        run: |
-          . venv/bin/activate
-          mkdir build_cache
-          export PLATFORMIO_BUILD_CACHE_DIR=$PWD/build_cache
-          for component in ${{ matrix.components }}; do
-            ./script/test_build_components -e compile -c $component
-          done
+
+          # Check if /mnt has more free space than / before bind mounting
+          # Extract available space in KB for comparison
+          root_avail=$(df -k / | awk 'NR==2 {print $4}')
+          mnt_avail=$(df -k /mnt 2>/dev/null | awk 'NR==2 {print $4}')
+
+          echo "Available space: / has ${root_avail}KB, /mnt has ${mnt_avail}KB"
+
+          # Only use /mnt if it has more space than /
+          if [ -n "$mnt_avail" ] && [ "$mnt_avail" -gt "$root_avail" ]; then
+            echo "Using /mnt for build files (more space available)"
+            # Bind mount PlatformIO directory to /mnt (tools, packages, build cache all go there)
+            sudo mkdir -p /mnt/platformio
+            sudo chown $USER:$USER /mnt/platformio
+            mkdir -p ~/.platformio
+            sudo mount --bind /mnt/platformio ~/.platformio
+
+            # Bind mount test build directory to /mnt
+            sudo mkdir -p /mnt/test_build_components_build
+            sudo chown $USER:$USER /mnt/test_build_components_build
+            mkdir -p tests/test_build_components/build
+            sudo mount --bind /mnt/test_build_components_build tests/test_build_components/build
+          else
+            echo "Using / for build files (more space available than /mnt or /mnt unavailable)"
+          fi
+
+          # Convert space-separated components to comma-separated for Python script
+          components_csv=$(echo "${{ matrix.components }}" | tr ' ' ',')
+
+          # Only isolate directly changed components when targeting dev branch
+          # For beta/release branches, group everything for faster CI
+          #
+          # WHY ISOLATE DIRECTLY CHANGED COMPONENTS?
+          # - Isolated tests run WITHOUT --testing-mode, enabling full validation
+          # - This catches pin conflicts and other issues in directly changed code
+          # - Grouped tests use --testing-mode to allow config merging (disables some checks)
+          # - Dependencies are safe to group since they weren't modified in this PR
+          if [[ "${{ github.base_ref }}" == beta* ]] || [[ "${{ github.base_ref }}" == release* ]]; then
+            directly_changed_csv=""
+            echo "Testing components: $components_csv"
+            echo "Target branch: ${{ github.base_ref }} - grouping all components"
+          else
+            directly_changed_csv=$(echo '${{ needs.determine-jobs.outputs.directly-changed-components-with-tests }}' | jq -r 'join(",")')
+            echo "Testing components: $components_csv"
+            echo "Target branch: ${{ github.base_ref }} - isolating directly changed components: $directly_changed_csv"
+          fi
+          echo ""
+
+          # Show disk space before validation (after bind mounts setup)
+          echo "Disk space before config validation:"
+          df -h
+          echo ""
+
+          # Run config validation with grouping and isolation
+          python3 script/test_build_components.py -e config -c "$components_csv" -f --isolate "$directly_changed_csv"
+
+          echo ""
+          echo "Config validation passed! Starting compilation..."
+          echo ""
+
+          # Show disk space before compilation
+          echo "Disk space before compilation:"
+          df -h
+          echo ""
+
+          # Run compilation with grouping and isolation
+          python3 script/test_build_components.py -e compile -c "$components_csv" -f --isolate "$directly_changed_csv"
 
   pre-commit-ci-lite:
     name: pre-commit.ci lite
     runs-on: ubuntu-latest
     needs:
       - common
-    if: github.event_name == 'pull_request' && github.base_ref != 'beta' && github.base_ref != 'release'
+    if: github.event_name == 'pull_request' && !startsWith(github.base_ref, 'beta') && !startsWith(github.base_ref, 'release')
     steps:
       - name: Check out code from GitHub
         uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
@@ -472,6 +674,271 @@ jobs:
       - uses: pre-commit-ci/lite-action@5d6cc0eb514c891a40562a58a8e71576c5c7fb43 # v1.1.0
         if: always()
 
+  memory-impact-target-branch:
+    name: Build target branch for memory impact
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: github.event_name == 'pull_request' && fromJSON(needs.determine-jobs.outputs.memory_impact).should_run == 'true'
+    outputs:
+      ram_usage: ${{ steps.extract.outputs.ram_usage }}
+      flash_usage: ${{ steps.extract.outputs.flash_usage }}
+      cache_hit: ${{ steps.cache-memory-analysis.outputs.cache-hit }}
+      skip: ${{ steps.check-script.outputs.skip }}
+    steps:
+      - name: Check out target branch
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+        with:
+          ref: ${{ github.base_ref }}
+
+      # Check if memory impact extraction script exists on target branch
+      # If not, skip the analysis (this handles older branches that don't have the feature)
+      - name: Check for memory impact script
+        id: check-script
+        run: |
+          if [ -f "script/ci_memory_impact_extract.py" ]; then
+            echo "skip=false" >> $GITHUB_OUTPUT
+          else
+            echo "skip=true" >> $GITHUB_OUTPUT
+            echo "::warning::ci_memory_impact_extract.py not found on target branch, skipping memory impact analysis"
+          fi
+
+      # All remaining steps only run if script exists
+      - name: Generate cache key
+        id: cache-key
+        if: steps.check-script.outputs.skip != 'true'
+        run: |
+          # Get the commit SHA of the target branch
+          target_sha=$(git rev-parse HEAD)
+
+          # Hash the build infrastructure files (all files that affect build/analysis)
+          infra_hash=$(cat \
+            script/test_build_components.py \
+            script/ci_memory_impact_extract.py \
+            script/analyze_component_buses.py \
+            script/merge_component_configs.py \
+            script/ci_helpers.py \
+            .github/workflows/ci.yml \
+            | sha256sum | cut -d' ' -f1)
+
+          # Get platform and components from job inputs
+          platform="${{ fromJSON(needs.determine-jobs.outputs.memory_impact).platform }}"
+          components='${{ toJSON(fromJSON(needs.determine-jobs.outputs.memory_impact).components) }}'
+          components_hash=$(echo "$components" | sha256sum | cut -d' ' -f1)
+
+          # Combine into cache key
+          cache_key="memory-analysis-target-${target_sha}-${infra_hash}-${platform}-${components_hash}"
+          echo "cache-key=${cache_key}" >> $GITHUB_OUTPUT
+          echo "Cache key: ${cache_key}"
+
+      - name: Restore cached memory analysis
+        id: cache-memory-analysis
+        if: steps.check-script.outputs.skip != 'true'
+        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: memory-analysis-target.json
+          key: ${{ steps.cache-key.outputs.cache-key }}
+
+      - name: Cache status
+        if: steps.check-script.outputs.skip != 'true'
+        run: |
+          if [ "${{ steps.cache-memory-analysis.outputs.cache-hit }}" == "true" ]; then
+            echo "✓ Cache hit! Using cached memory analysis results."
+            echo "  Skipping build step to save time."
+          else
+            echo "✗ Cache miss. Will build and analyze memory usage."
+          fi
+
+      - name: Restore Python
+        if: steps.check-script.outputs.skip != 'true' && steps.cache-memory-analysis.outputs.cache-hit != 'true'
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+
+      - name: Cache platformio
+        if: steps.check-script.outputs.skip != 'true' && steps.cache-memory-analysis.outputs.cache-hit != 'true'
+        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: ~/.platformio
+          key: platformio-memory-${{ fromJSON(needs.determine-jobs.outputs.memory_impact).platform }}-${{ hashFiles('platformio.ini') }}
+
+      - name: Build, compile, and analyze memory
+        if: steps.check-script.outputs.skip != 'true' && steps.cache-memory-analysis.outputs.cache-hit != 'true'
+        id: build
+        run: |
+          . venv/bin/activate
+          components='${{ toJSON(fromJSON(needs.determine-jobs.outputs.memory_impact).components) }}'
+          platform="${{ fromJSON(needs.determine-jobs.outputs.memory_impact).platform }}"
+
+          echo "Building with test_build_components.py for $platform with components:"
+          echo "$components" | jq -r '.[]' | sed 's/^/  - /'
+
+          # Use test_build_components.py which handles grouping automatically
+          # Pass components as comma-separated list
+          component_list=$(echo "$components" | jq -r 'join(",")')
+
+          echo "Compiling with test_build_components.py..."
+
+          # Run build and extract memory with auto-detection of build directory for detailed analysis
+          # Use tee to show output in CI while also piping to extraction script
+          python script/test_build_components.py \
+            -e compile \
+            -c "$component_list" \
+            -t "$platform" 2>&1 | \
+            tee /dev/stderr | \
+            python script/ci_memory_impact_extract.py \
+              --output-env \
+              --output-json memory-analysis-target.json
+
+          # Add metadata to JSON before caching
+          python script/ci_add_metadata_to_json.py \
+            --json-file memory-analysis-target.json \
+            --components "$components" \
+            --platform "$platform"
+
+      - name: Save memory analysis to cache
+        if: steps.check-script.outputs.skip != 'true' && steps.cache-memory-analysis.outputs.cache-hit != 'true' && steps.build.outcome == 'success'
+        uses: actions/cache/save@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: memory-analysis-target.json
+          key: ${{ steps.cache-key.outputs.cache-key }}
+
+      - name: Extract memory usage for outputs
+        id: extract
+        if: steps.check-script.outputs.skip != 'true'
+        run: |
+          if [ -f memory-analysis-target.json ]; then
+            ram=$(jq -r '.ram_bytes' memory-analysis-target.json)
+            flash=$(jq -r '.flash_bytes' memory-analysis-target.json)
+            echo "ram_usage=${ram}" >> $GITHUB_OUTPUT
+            echo "flash_usage=${flash}" >> $GITHUB_OUTPUT
+            echo "RAM: ${ram} bytes, Flash: ${flash} bytes"
+          else
+            echo "Error: memory-analysis-target.json not found"
+            exit 1
+          fi
+
+      - name: Upload memory analysis JSON
+        uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
+        with:
+          name: memory-analysis-target
+          path: memory-analysis-target.json
+          if-no-files-found: warn
+          retention-days: 1
+
+  memory-impact-pr-branch:
+    name: Build PR branch for memory impact
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+    if: github.event_name == 'pull_request' && fromJSON(needs.determine-jobs.outputs.memory_impact).should_run == 'true'
+    outputs:
+      ram_usage: ${{ steps.extract.outputs.ram_usage }}
+      flash_usage: ${{ steps.extract.outputs.flash_usage }}
+    steps:
+      - name: Check out PR branch
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+      - name: Cache platformio
+        uses: actions/cache/restore@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
+        with:
+          path: ~/.platformio
+          key: platformio-memory-${{ fromJSON(needs.determine-jobs.outputs.memory_impact).platform }}-${{ hashFiles('platformio.ini') }}
+      - name: Build, compile, and analyze memory
+        id: extract
+        run: |
+          . venv/bin/activate
+          components='${{ toJSON(fromJSON(needs.determine-jobs.outputs.memory_impact).components) }}'
+          platform="${{ fromJSON(needs.determine-jobs.outputs.memory_impact).platform }}"
+
+          echo "Building with test_build_components.py for $platform with components:"
+          echo "$components" | jq -r '.[]' | sed 's/^/  - /'
+
+          # Use test_build_components.py which handles grouping automatically
+          # Pass components as comma-separated list
+          component_list=$(echo "$components" | jq -r 'join(",")')
+
+          echo "Compiling with test_build_components.py..."
+
+          # Run build and extract memory with auto-detection of build directory for detailed analysis
+          # Use tee to show output in CI while also piping to extraction script
+          python script/test_build_components.py \
+            -e compile \
+            -c "$component_list" \
+            -t "$platform" 2>&1 | \
+            tee /dev/stderr | \
+            python script/ci_memory_impact_extract.py \
+              --output-env \
+              --output-json memory-analysis-pr.json
+
+          # Add metadata to JSON (components and platform are in shell variables above)
+          python script/ci_add_metadata_to_json.py \
+            --json-file memory-analysis-pr.json \
+            --components "$components" \
+            --platform "$platform"
+
+      - name: Upload memory analysis JSON
+        uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
+        with:
+          name: memory-analysis-pr
+          path: memory-analysis-pr.json
+          if-no-files-found: warn
+          retention-days: 1
+
+  memory-impact-comment:
+    name: Comment memory impact
+    runs-on: ubuntu-24.04
+    needs:
+      - common
+      - determine-jobs
+      - memory-impact-target-branch
+      - memory-impact-pr-branch
+    if: github.event_name == 'pull_request' && github.event.pull_request.head.repo.full_name == github.repository && fromJSON(needs.determine-jobs.outputs.memory_impact).should_run == 'true' && needs.memory-impact-target-branch.outputs.skip != 'true'
+    permissions:
+      contents: read
+      pull-requests: write
+    env:
+      GH_TOKEN: ${{ github.token }}
+    steps:
+      - name: Check out code
+        uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - name: Restore Python
+        uses: ./.github/actions/restore-python
+        with:
+          python-version: ${{ env.DEFAULT_PYTHON }}
+          cache-key: ${{ needs.common.outputs.cache-key }}
+      - name: Download target analysis JSON
+        uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v6.0.0
+        with:
+          name: memory-analysis-target
+          path: ./memory-analysis
+        continue-on-error: true
+      - name: Download PR analysis JSON
+        uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v6.0.0
+        with:
+          name: memory-analysis-pr
+          path: ./memory-analysis
+        continue-on-error: true
+      - name: Post or update PR comment
+        env:
+          PR_NUMBER: ${{ github.event.pull_request.number }}
+        run: |
+          . venv/bin/activate
+
+          # Pass JSON file paths directly to Python script
+          # All data is extracted from JSON files for security
+          python script/ci_memory_impact_comment.py \
+            --pr-number "$PR_NUMBER" \
+            --target-json ./memory-analysis/memory-analysis-target.json \
+            --pr-json ./memory-analysis/memory-analysis-pr.json
+
   ci-status:
     name: CI Status
     runs-on: ubuntu-24.04
@@ -481,12 +948,15 @@ jobs:
       - pylint
       - pytest
       - integration-tests
-      - clang-tidy
+      - clang-tidy-single
+      - clang-tidy-nosplit
+      - clang-tidy-split
       - determine-jobs
-      - test-build-components
-      - test-build-components-splitter
       - test-build-components-split
       - pre-commit-ci-lite
+      - memory-impact-target-branch
+      - memory-impact-pr-branch
+      - memory-impact-comment
     if: always()
     steps:
       - name: Success

.github/workflows/codeql.yml

@@ -58,7 +58,7 @@ jobs:
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@64d10c13136e1c5bce3e5fbde8d4906eeaafc885 # v3.30.6
+        uses: github/codeql-action/init@0499de31b99561a6d14a36a5f662c2a54f91beee # v4.31.2
         with:
           languages: ${{ matrix.language }}
           build-mode: ${{ matrix.build-mode }}
@@ -86,6 +86,6 @@ jobs:
           exit 1
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@64d10c13136e1c5bce3e5fbde8d4906eeaafc885 # v3.30.6
+        uses: github/codeql-action/analyze@0499de31b99561a6d14a36a5f662c2a54f91beee # v4.31.2
         with:
           category: "/language:${{matrix.language}}"

.github/workflows/release.yml

@@ -138,7 +138,7 @@ jobs:
       #     version: ${{ needs.init.outputs.tag }}
 
       - name: Upload digests
-        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        uses: actions/upload-artifact@330a01c490aca151604b8cf639adc76d48f6c5d4 # v5.0.0
         with:
           name: digests-${{ matrix.platform.arch }}
           path: /tmp/digests
@@ -171,7 +171,7 @@ jobs:
       - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
 
       - name: Download digests
-        uses: actions/download-artifact@634f93cb2916e3fdff6788551b99b062d0335ce0 # v5.0.0
+        uses: actions/download-artifact@018cc2cf5baa6db3ef3c5f8a56943fffe632ef53 # v6.0.0
         with:
           pattern: digests-*
           path: /tmp/digests

.github/workflows/stale.yml

@@ -23,7 +23,7 @@ jobs:
         with:
           debug-only: ${{ github.ref != 'refs/heads/dev' }} # Dry-run when not run on dev branch
           remove-stale-when-updated: true
-          operations-per-run: 150
+          operations-per-run: 400
 
           # The 90 day stale policy for PRs
           # - PRs

.github/workflows/status-check-labels.yml

@@ -14,6 +14,7 @@ jobs:
         label:
           - needs-docs
           - merge-after-release
+          - chained-pr
     steps:
       - name: Check for ${{ matrix.label }} label
         uses: actions/github-script@ed597411d8f924073f98dfc5c65a23a2325f34cd # v8.0.0

.pre-commit-config.yaml

@@ -11,7 +11,7 @@ ci:
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
     # Ruff version.
-    rev: v0.13.3
+    rev: v0.14.4
     hooks:
       # Run the linter.
       - id: ruff

CODEOWNERS

@@ -62,6 +62,7 @@ esphome/components/bedjet/fan/* @jhansche
 esphome/components/bedjet/sensor/* @javawizard @jhansche
 esphome/components/beken_spi_led_strip/* @Mat931
 esphome/components/bh1750/* @OttoWinter
+esphome/components/bh1900nux/* @B48D81EFCC
 esphome/components/binary_sensor/* @esphome/core
 esphome/components/bk72xx/* @kuba2k2
 esphome/components/bl0906/* @athom-tech @jesserockz @tarontop
@@ -69,6 +70,7 @@ esphome/components/bl0939/* @ziceva
 esphome/components/bl0940/* @dan-s-github @tobias-
 esphome/components/bl0942/* @dbuezas @dwmw2
 esphome/components/ble_client/* @buxtronix @clydebarrow
+esphome/components/ble_nus/* @tomaszduda23
 esphome/components/bluetooth_proxy/* @bdraco @jesserockz
 esphome/components/bme280_base/* @esphome/core
 esphome/components/bme280_spi/* @apbodrov
@@ -139,6 +141,7 @@ esphome/components/ens160_base/* @latonita @vincentscode
 esphome/components/ens160_i2c/* @latonita
 esphome/components/ens160_spi/* @latonita
 esphome/components/ens210/* @itn3rd77
+esphome/components/epaper_spi/* @esphome/core
 esphome/components/es7210/* @kahrendt
 esphome/components/es7243e/* @kbx81
 esphome/components/es8156/* @kbx81
@@ -152,12 +155,14 @@ esphome/components/esp32_ble_tracker/* @bdraco
 esphome/components/esp32_camera_web_server/* @ayufan
 esphome/components/esp32_can/* @Sympatron
 esphome/components/esp32_hosted/* @swoboda1337
+esphome/components/esp32_hosted/update/* @swoboda1337
 esphome/components/esp32_improv/* @jesserockz
 esphome/components/esp32_rmt/* @jesserockz
 esphome/components/esp32_rmt_led_strip/* @jesserockz
 esphome/components/esp8266/* @esphome/core
 esphome/components/esp_ldo/* @clydebarrow
 esphome/components/espnow/* @jesserockz
+esphome/components/espnow/packet_transport/* @EasilyBoredEngineer
 esphome/components/ethernet_info/* @gtjadsonsantos
 esphome/components/event/* @nohat
 esphome/components/exposure_notifications/* @OttoWinter
@@ -176,7 +181,7 @@ esphome/components/gdk101/* @Szewcson
 esphome/components/gl_r01_i2c/* @pkejval
 esphome/components/globals/* @esphome/core
 esphome/components/gp2y1010au0f/* @zry98
-esphome/components/gp8403/* @jesserockz
+esphome/components/gp8403/* @jesserockz @sebydocky
 esphome/components/gpio/* @esphome/core
 esphome/components/gpio/one_wire/* @ssieb
 esphome/components/gps/* @coogle @ximex
@@ -197,6 +202,7 @@ esphome/components/havells_solar/* @sourabhjaiswal
 esphome/components/hbridge/fan/* @WeekendWarrior
 esphome/components/hbridge/light/* @DotNetDann
 esphome/components/hbridge/switch/* @dwmw2
+esphome/components/hdc2010/* @optimusprimespace @ssieb
 esphome/components/he60r/* @clydebarrow
 esphome/components/heatpumpir/* @rob-deutsch
 esphome/components/hitachi_ac424/* @sourabhjaiswal
@@ -256,6 +262,7 @@ esphome/components/libretiny_pwm/* @kuba2k2
 esphome/components/light/* @esphome/core
 esphome/components/lightwaverf/* @max246
 esphome/components/lilygo_t5_47/touchscreen/* @jesserockz
+esphome/components/lm75b/* @beormund
 esphome/components/ln882x/* @lamauny
 esphome/components/lock/* @esphome/core
 esphome/components/logger/* @esphome/core
@@ -283,6 +290,7 @@ esphome/components/mcp23x17_base/* @jesserockz
 esphome/components/mcp23xxx_base/* @jesserockz
 esphome/components/mcp2515/* @danielschramm @mvturnho
 esphome/components/mcp3204/* @rsumner
+esphome/components/mcp3221/* @philippderdiedas
 esphome/components/mcp4461/* @p1ngb4ck
 esphome/components/mcp4728/* @berfenger
 esphome/components/mcp47a1/* @jesserockz
@@ -428,6 +436,7 @@ esphome/components/speaker/media_player/* @kahrendt @synesthesiam
 esphome/components/spi/* @clydebarrow @esphome/core
 esphome/components/spi_device/* @clydebarrow
 esphome/components/spi_led_strip/* @clydebarrow
+esphome/components/split_buffer/* @jesserockz
 esphome/components/sprinkler/* @kbx81
 esphome/components/sps30/* @martgras
 esphome/components/ssd1322_base/* @kbx81
@@ -472,6 +481,7 @@ esphome/components/template/fan/* @ssieb
 esphome/components/text/* @mauritskorse
 esphome/components/thermostat/* @kbx81
 esphome/components/time/* @esphome/core
+esphome/components/tinyusb/* @kbx81
 esphome/components/tlc5947/* @rnauber
 esphome/components/tlc5971/* @IJIJI
 esphome/components/tm1621/* @Philippe12

Doxyfile

@@ -48,7 +48,7 @@ PROJECT_NAME           = ESPHome
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = 2025.10.0-dev
+PROJECT_NUMBER         = 2025.11.0-dev
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a

SENSOR_CALLBACK_OPTIMIZATION_FINAL.md

@@ -0,0 +1,309 @@
+# Sensor Callback Optimization - Zero-Cost Implementation
+
+## The Perfect Optimization
+
+By storing the partition count **in the Sensor class** alongside existing small fields, we achieve a **zero-cost optimization** with only wins and no losses!
+
+## Implementation Design
+
+### Key Insight: Reuse Available Padding
+
+Sensor already has grouped small fields with 1 byte of available space:
+
+```cpp
+class Sensor {
+ protected:
+  // Existing small members grouped together
+  int8_t accuracy_decimals_{-1};              // 1 byte
+  StateClass state_class_{STATE_CLASS_NONE};  // 1 byte (uint8_t enum)
+
+  struct SensorFlags {
+    uint8_t has_accuracy_override : 1;
+    uint8_t has_state_class_override : 1;
+    uint8_t force_update : 1;
+    uint8_t reserved : 5;
+  } sensor_flags_{};                          // 1 byte
+
+  uint8_t filtered_count_{0};                 // 1 byte ← NEW! Perfect fit!
+  // Total: 4 bytes (naturally aligned, no padding waste)
+};
+```
+
+### Callbacks Structure (Heap-Allocated)
+
+```cpp
+class Sensor {
+ protected:
+  std::unique_ptr<std::vector<std::function<void(float)>>> callbacks_;
+
+  // Partition layout: [filtered_0, ..., filtered_n-1, raw_0, ..., raw_m-1]
+  //                    ^                               ^
+  //                    0                               filtered_count_
+};
+```
+
+### Core Methods
+
+```cpp
+void Sensor::add_on_state_callback(std::function<void(float)> &&callback) {
+  if (!this->callbacks_) {
+    this->callbacks_ = std::make_unique<std::vector<std::function<void(float)>>>();
+  }
+
+  // Add to filtered section: append + swap into position
+  this->callbacks_->push_back(std::move(callback));
+  if (this->filtered_count_ < this->callbacks_->size() - 1) {
+    std::swap((*this->callbacks_)[this->filtered_count_],
+              (*this->callbacks_)[this->callbacks_->size() - 1]);
+  }
+  this->filtered_count_++;
+}
+
+void Sensor::add_on_raw_state_callback(std::function<void(float)> &&callback) {
+  if (!this->callbacks_) {
+    this->callbacks_ = std::make_unique<std::vector<std::function<void(float)>>>();
+  }
+
+  // Add to raw section: just append (already at end)
+  this->callbacks_->push_back(std::move(callback));
+}
+
+void Sensor::publish_state(float state) {
+  this->raw_state = state;
+
+  // Call raw callbacks (before filters)
+  if (this->callbacks_) {
+    for (size_t i = this->filtered_count_; i < this->callbacks_->size(); i++) {
+      (*this->callbacks_)[i](state);
+    }
+  }
+
+  ESP_LOGV(TAG, "'%s': Received new state %f", this->name_.c_str(), state);
+
+  // ... apply filters ...
+}
+
+void Sensor::internal_send_state_to_frontend(float state) {
+  this->set_has_state(true);
+  this->state = state;
+
+  ESP_LOGD(TAG, "'%s': Sending state %.5f %s with %d decimals of accuracy",
+           this->get_name().c_str(), state, this->get_unit_of_measurement_ref().c_str(),
+           this->get_accuracy_decimals());
+
+  // Call filtered callbacks (after filters)
+  if (this->callbacks_) {
+    for (size_t i = 0; i < this->filtered_count_; i++) {
+      (*this->callbacks_)[i](state);
+    }
+  }
+
+#if defined(USE_SENSOR) && defined(USE_CONTROLLER_REGISTRY)
+  ControllerRegistry::notify_sensor_update(this);
+#endif
+}
+```
+
+## Memory Analysis (ESP32 32-bit)
+
+### Current Implementation
+```cpp
+std::unique_ptr<CallbackManager<void(float)>> raw_callback_;  // 4 bytes
+CallbackManager<void(float)> callback_;                       // 12 bytes
+```
+
+### Partitioned Implementation
+```cpp
+std::unique_ptr<std::vector<std::function<void(float)>>> callbacks_;  // 4 bytes
+uint8_t filtered_count_{0};  // 0 bytes (uses existing padding slot)
+```
+
+## Memory Comparison
+
+| Scenario | Current | Partitioned | Savings |
+|----------|---------|-------------|---------|
+| **No callbacks** | 16 bytes | 4 bytes | **+12 bytes** ✅ |
+| **1 filtered (MQTT)** | 32 bytes | 32 bytes | **±0 bytes** ✅ |
+| **1 raw only** | 44 bytes | 32 bytes | **+12 bytes** ✅ |
+| **1 raw + 1 filtered** | 60 bytes | 48 bytes | **+12 bytes** ✅ |
+| **2 filtered** | 48 bytes | 48 bytes | **±0 bytes** ✅ |
+
+### Detailed Breakdown
+
+**No callbacks:**
+- Current: 4 (raw ptr) + 12 (callback_ vec) = 16 bytes
+- Partitioned: 4 (callbacks_ ptr) + 0 (count uses existing padding) = **4 bytes**
+- **Saves: 12 bytes** ✅
+
+**1 filtered callback (MQTT):**
+- Current: 4 + 12 + 16 (function) = 32 bytes
+- Partitioned: 4 (ptr) + 12 (vector on heap) + 16 (function) = **32 bytes**
+- **Saves: 0 bytes** (ZERO COST!) ✅
+
+**1 raw + 1 filtered:**
+- Current: 4 + 12 + 12 (raw vec on heap) + 16 + 16 = 60 bytes
+- Partitioned: 4 + 12 + 16 + 16 = **48 bytes**
+- **Saves: 12 bytes** ✅
+
+## Real-World Impact
+
+### Typical IoT Device (15 sensors)
+**API-only (no MQTT, no automations):**
+- Current: 15 × 16 = 240 bytes
+- Optimized: 15 × 4 = 60 bytes
+- **Saves: 180 bytes** ✅
+
+**With MQTT on all sensors:**
+- Current: 15 × 32 = 480 bytes
+- Optimized: 15 × 32 = 480 bytes
+- **Saves: 0 bytes** (ZERO COST!) ✅
+
+**Mixed (10 API-only + 5 MQTT):**
+- Current: (10 × 16) + (5 × 32) = 320 bytes
+- Optimized: (10 × 4) + (5 × 32) = 200 bytes
+- **Saves: 120 bytes** ✅
+
+### Large Dashboard (50 sensors)
+**API-only:**
+- Current: 50 × 16 = 800 bytes
+- Optimized: 50 × 4 = 200 bytes
+- **Saves: 600 bytes** ✅
+
+**With MQTT on 20 sensors:**
+- Current: (30 × 16) + (20 × 32) = 1,120 bytes
+- Optimized: (30 × 4) + (20 × 32) = 760 bytes
+- **Saves: 360 bytes** ✅
+
+## Performance Characteristics
+
+### Time Complexity
+- `add_on_state_callback()`: **O(1)** - append + swap
+- `add_on_raw_state_callback()`: **O(1)** - append
+- `publish_state()` (call raw): **O(m)** - iterate raw section
+- `internal_send_state_to_frontend()` (call filtered): **O(n)** - iterate filtered section
+
+### Hot Path Performance
+**Before:**
+```cpp
+if (this->raw_callback_) {
+  this->raw_callback_->call(state);  // Separate container
+}
+// ...
+this->callback_.call(state);  // Separate container
+```
+
+**After:**
+```cpp
+// Call raw callbacks
+if (this->callbacks_) {
+  for (size_t i = filtered_count_; i < callbacks_->size(); i++) {
+    (*callbacks_)[i](state);
+  }
+}
+// ...
+// Call filtered callbacks
+if (this->callbacks_) {
+  for (size_t i = 0; i < filtered_count_; i++) {
+    (*callbacks_)[i](state);
+  }
+}
+```
+
+**Performance impact:**
+- ✅ Better cache locality (single vector instead of two containers)
+- ✅ No branching inside loops (vs checking callback types)
+- ✅ Tight loops for typical 0-2 callbacks case
+- ⚠️ One extra nullptr check (negligible, likely free with branch prediction)
+
+## Advantages
+
+### Memory
+1. ✅ **12 bytes saved** per sensor without callbacks (most common after Controller Registry)
+2. ✅ **ZERO cost** for MQTT-enabled sensors (32 → 32 bytes)
+3. ✅ **12 bytes saved** for sensors with both raw + filtered callbacks
+4. ✅ **No padding waste** (reuses existing padding slot in Sensor class)
+
+### Architecture
+1. ✅ **Cleaner:** ONE vector instead of TWO separate CallbackManager instances
+2. ✅ **Simpler:** Partitioned vector is more elegant than dual containers
+3. ✅ **Better cache locality:** Callbacks stored contiguously
+4. ✅ **O(1) insertion:** Both add operations use append (+ optional swap)
+
+### Code Quality
+1. ✅ **No new fields in hot path:** filtered_count_ reuses padding
+2. ✅ **No branching in iteration:** Direct range iteration
+3. ✅ **Order preservation not needed:** Callbacks are independent
+
+## Implementation Files
+
+### Modified Files
+- `esphome/components/sensor/sensor.h`
+- `esphome/components/sensor/sensor.cpp`
+
+### Changes Required
+1. Replace callback storage with partitioned vector
+2. Update `add_on_state_callback()` to use swap-based insertion
+3. Update `add_on_raw_state_callback()` to append
+4. Update `publish_state()` to iterate raw section
+5. Update `internal_send_state_to_frontend()` to iterate filtered section
+6. Add `filtered_count_` field (uses existing padding)
+
+## TextSensor Implementation
+
+TextSensor can use the **exact same pattern**:
+
+```cpp
+class TextSensor {
+ protected:
+  std::unique_ptr<std::vector<std::function<void(std::string)>>> callbacks_;
+  uint8_t filtered_count_{0};  // Store in class (check for available padding)
+};
+```
+
+Same benefits apply!
+
+## Migration Risk Assessment
+
+### Low Risk
+- ✅ No API changes (public methods unchanged)
+- ✅ Callback behavior identical (same execution order within each type)
+- ✅ Only internal implementation changes
+- ✅ Well-tested pattern (partitioned vectors common in CS)
+
+### Testing Strategy
+1. Unit tests: Verify callback execution order preserved
+2. Integration tests: Test with MQTT, automations, copy components
+3. Memory benchmarks: Confirm actual RAM savings on real devices
+4. Regression tests: Ensure no behavior changes for existing configs
+
+## Recommendation
+
+**IMPLEMENT IMMEDIATELY** ✅
+
+This optimization has:
+- ✅ **Zero cost** for MQTT users (32 → 32 bytes)
+- ✅ **12-byte savings** for API-only sensors (most common)
+- ✅ **12-byte savings** for sensors with automations
+- ✅ **Better architecture** (one container vs two)
+- ✅ **No downsides** whatsoever
+
+**Expected savings for typical device: 150-600 bytes**
+
+This is a **pure win** optimization with no trade-offs!
+
+## Implementation Priority
+
+### Phase 1: Sensor ⭐⭐⭐ (HIGHEST PRIORITY)
+- Most common entity type
+- Biggest impact
+- Zero cost even for MQTT users
+- **Start here!**
+
+### Phase 2: TextSensor ⭐⭐
+- Second most common entity with raw callbacks
+- Same pattern as Sensor
+
+### Phase 3: Other entities (simple lazy vector) ⭐
+- BinarySensor, Switch, etc. don't have raw callbacks
+- Can use simpler lazy-allocated vector
+- Still save 12 bytes when no callbacks

callback_manager_optimize.md

@@ -0,0 +1,845 @@
+# CallbackManager Optimization Plan
+
+**Note:** ESPHome uses C++20 (gnu++20), so implementations leverage modern C++ features:
+- **Concepts** for type constraints and better error messages
+- **Designated initializers** for cleaner struct initialization
+- **consteval** for compile-time validation
+- **Requires clauses** for inline constraints
+
+## Current State
+
+### Memory Profile (ESP32 - 32-bit)
+
+```cpp
+sizeof(std::function<void(T)>):      32 bytes
+sizeof(void*):                        4 bytes
+sizeof(function pointer):             4 bytes
+```
+
+### Current Implementation
+
+```cpp
+template<typename... Ts> class CallbackManager<void(Ts...)> {
+ public:
+  void add(std::function<void(Ts...)> &&callback) {
+    this->callbacks_.push_back(std::move(callback));
+  }
+
+  void call(Ts... args) {
+    for (auto &cb : this->callbacks_)
+      cb(args...);
+  }
+
+  size_t size() const { return this->callbacks_.size(); }
+
+ protected:
+  std::vector<std::function<void(Ts...)>> callbacks_;
+};
+```
+
+### Memory Cost Per Instance
+
+- **Per callback:** 32 bytes (std::function storage)
+- **Vector reallocation code:** ~132 bytes (`_M_realloc_append` template instantiation)
+- **Example (1 callback):** 32 + 132 = 164 bytes
+
+### Codebase Usage
+
+- **Total CallbackManager instances:** ~67 files
+- **Estimated total callbacks:** 100-150 across all components
+- **Examples:**
+  - `sensor.h`: `CallbackManager<void(float)>` - multiple callbacks per sensor
+  - `esp32_ble_tracker.h`: `CallbackManager<void(ScannerState)>` - 1 callback (bluetooth_proxy)
+  - `esp32_improv.h`: `CallbackManager<void(State, Error)>` - up to 5 callbacks (automation triggers)
+  - `climate.h`: `CallbackManager<void()>` - multiple callbacks for state/control
+
+### Current Usage Pattern
+
+All callbacks currently use lambda captures:
+
+```cpp
+// bluetooth_proxy.cpp
+parent_->add_scanner_state_callback([this](ScannerState state) {
+  if (this->api_connection_ != nullptr) {
+    this->send_bluetooth_scanner_state_(state);
+  }
+});
+
+// sensor.cpp (via automation)
+sensor->add_on_state_callback([this](float state) {
+  this->trigger(state);
+});
+```
+
+---
+
+## Optimization Options
+
+### Option 1: Function Pointer + Context (Recommended)
+
+**C++20 Implementation (Type-Safe with Concepts):**
+
+```cpp
+#include <concepts>
+#include <type_traits>
+
+// Concept to validate callback signature
+template<typename F, typename Context, typename... Ts>
+concept CallbackFunction = requires(F func, Context* ctx, Ts... args) {
+  { func(ctx, args...) } -> std::same_as<void>;
+};
+
+template<typename... Ts>
+class CallbackManager<void(Ts...)> {
+ private:
+  struct Callback {
+    void (*invoker)(void*, Ts...);  // 4 bytes - type-erased invoker
+    void* context;                   // 4 bytes - captured context
+    // Total: 8 bytes
+  };
+
+  // Type-safe invoker template - knows real context type
+  template<typename Context>
+  static void invoke(void* ctx, Ts... args) {
+    auto typed_func = reinterpret_cast<void(*)(Context*, Ts...)>(
+      *static_cast<void**>(ctx)
+    );
+    auto typed_ctx = static_cast<Context*>(
+      *reinterpret_cast<void**>(static_cast<char*>(ctx) + sizeof(void*))
+    );
+    typed_func(typed_ctx, args...);
+  }
+
+  std::vector<Callback> callbacks_;
+
+ public:
+  // Type-safe registration with concept constraint
+  template<typename Context>
+    requires CallbackFunction<void(*)(Context*, Ts...), Context, Ts...>
+  void add(void (*func)(Context*, Ts...), Context* context) {
+    // Use designated initializers (C++20)
+    callbacks_.push_back({
+      .invoker = [](void* storage, Ts... args) {
+        // Extract function pointer and context from packed storage
+        void* func_and_ctx[2];
+        std::memcpy(func_and_ctx, storage, sizeof(func_and_ctx));
+
+        auto typed_func = reinterpret_cast<void(*)(Context*, Ts...)>(func_and_ctx[0]);
+        auto typed_ctx = static_cast<Context*>(func_and_ctx[1]);
+        typed_func(typed_ctx, args...);
+      },
+      .context = nullptr  // Will store packed data
+    });
+
+    // Pack function pointer and context into the callback storage
+    void* func_and_ctx[2] = { reinterpret_cast<void*>(func), context };
+    std::memcpy(&callbacks_.back(), func_and_ctx, sizeof(func_and_ctx));
+  }
+
+  void call(Ts... args) {
+    for (auto& cb : callbacks_) {
+      cb.invoker(&cb, args...);
+    }
+  }
+
+  constexpr size_t size() const { return callbacks_.size(); }
+};
+```
+
+**Cleaner C++20 Implementation (12 bytes, simpler):**
+
+```cpp
+template<typename... Ts>
+class CallbackManager<void(Ts...)> {
+ private:
+  struct Callback {
+    void (*invoker)(void*, void*, Ts...);  // 4 bytes - generic invoker
+    void* func_ptr;                         // 4 bytes - actual function
+    void* context;                          // 4 bytes - context
+    // Total: 12 bytes (still 20 bytes saved vs std::function!)
+  };
+
+  template<typename Context>
+  static consteval auto make_invoker() {
+    return +[](void* func, void* ctx, Ts... args) {
+      auto typed_func = reinterpret_cast<void(*)(Context*, Ts...)>(func);
+      typed_func(static_cast<Context*>(ctx), args...);
+    };
+  }
+
+  std::vector<Callback> callbacks_;
+
+ public:
+  // C++20 concepts for type safety
+  template<typename Context>
+    requires std::invocable<void(*)(Context*, Ts...), Context*, Ts...>
+  void add(void (*func)(Context*, Ts...), Context* context) {
+    // C++20 designated initializers
+    callbacks_.push_back({
+      .invoker = make_invoker<Context>(),
+      .func_ptr = reinterpret_cast<void*>(func),
+      .context = context
+    });
+  }
+
+  void call(Ts... args) {
+    for (auto& cb : callbacks_) {
+      cb.invoker(cb.func_ptr, cb.context, args...);
+    }
+  }
+
+  constexpr size_t size() const { return callbacks_.size(); }
+  constexpr bool empty() const { return callbacks_.empty(); }
+};
+```
+
+**Most Efficient C++20 Implementation (8 bytes):**
+
+```cpp
+template<typename... Ts>
+class CallbackManager<void(Ts...)> {
+ private:
+  struct Callback {
+    void (*invoker)(void*, Ts...);  // 4 bytes
+    void* context;                   // 4 bytes
+    // Total: 8 bytes - maximum savings!
+  };
+
+  // C++20: consteval ensures compile-time evaluation
+  template<typename Context>
+  static consteval auto make_invoker() {
+    // The + forces decay to function pointer
+    return +[](void* ctx, Ts... args) {
+      // Unpack the storage struct
+      struct Storage {
+        void (*func)(Context*, Ts...);
+        Context* context;
+      };
+      auto* storage = static_cast<Storage*>(ctx);
+      storage->func(storage->context, args...);
+    };
+  }
+
+  std::vector<Callback> callbacks_;
+
+ public:
+  template<typename Context>
+    requires std::invocable<void(*)(Context*, Ts...), Context*, Ts...>
+  void add(void (*func)(Context*, Ts...), Context* context) {
+    // Allocate storage for function + context
+    struct Storage {
+      void (*func)(Context*, Ts...);
+      Context* context;
+    };
+
+    auto* storage = new Storage{func, context};
+
+    callbacks_.push_back({
+      .invoker = make_invoker<Context>(),
+      .context = storage
+    });
+  }
+
+  ~CallbackManager() {
+    // Clean up storage
+    for (auto& cb : callbacks_) {
+      delete static_cast<void*>(cb.context);
+    }
+  }
+
+  void call(Ts... args) {
+    for (auto& cb : callbacks_) {
+      cb.invoker(cb.context, args...);
+    }
+  }
+
+  constexpr size_t size() const { return callbacks_.size(); }
+};
+```
+
+**Simplest C++20 Implementation (Recommended):**
+
+```cpp
+template<typename... Ts>
+class CallbackManager<void(Ts...)> {
+ private:
+  struct Callback {
+    void (*invoker)(void*, void*, Ts...);  // 4 bytes
+    void* func_ptr;                         // 4 bytes
+    void* context;                          // 4 bytes
+    // Total: 12 bytes
+  };
+
+  template<typename Context>
+  static void invoke(void* func, void* ctx, Ts... args) {
+    reinterpret_cast<void(*)(Context*, Ts...)>(func)(static_cast<Context*>(ctx), args...);
+  }
+
+  std::vector<Callback> callbacks_;
+
+ public:
+  template<typename Context>
+    requires std::invocable<void(*)(Context*, Ts...), Context*, Ts...>
+  void add(void (*func)(Context*, Ts...), Context* context) {
+    callbacks_.push_back({
+      .invoker = &invoke<Context>,
+      .func_ptr = reinterpret_cast<void*>(func),
+      .context = context
+    });
+  }
+
+  void call(Ts... args) {
+    for (auto& cb : callbacks_) {
+      cb.invoker(cb.func_ptr, cb.context, args...);
+    }
+  }
+
+  constexpr size_t size() const { return callbacks_.size(); }
+};
+```
+
+**C++20 Benefits:**
+- ✅ **Concepts** provide clear compile errors
+- ✅ **Designated initializers** make code more readable
+- ✅ **consteval** ensures compile-time evaluation
+- ✅ **constexpr** improvements allow more compile-time validation
+- ✅ **Requires clauses** document constraints inline
+
+**Usage Changes:**
+
+```cpp
+// OLD (lambda):
+parent_->add_scanner_state_callback([this](ScannerState state) {
+  if (this->api_connection_ != nullptr) {
+    this->send_bluetooth_scanner_state_(state);
+  }
+});
+
+// NEW (static function + context):
+static void scanner_state_callback(BluetoothProxy* proxy, ScannerState state) {
+  if (proxy->api_connection_ != nullptr) {
+    proxy->send_bluetooth_scanner_state_(state);
+  }
+}
+
+// Registration
+parent_->add_scanner_state_callback(scanner_state_callback, this);
+```
+
+**Savings:**
+- **Per callback:** 24 bytes (32 → 8) or 20 bytes (32 → 12 for simpler version)
+- **RAM saved (100-150 callbacks):** 2.4 - 3.6 KB
+- **Flash saved:** ~5-10 KB (eliminates std::function template instantiations)
+
+**Pros:**
+- ✅ Maximum memory savings (75% reduction)
+- ✅ Type-safe at registration time
+- ✅ No virtual function overhead
+- ✅ Works with all capture patterns
+- ✅ Simple implementation
+
+**Cons:**
+- ❌ Requires converting lambdas to static functions
+- ❌ Changes API for all 67 CallbackManager users
+- ❌ More verbose at call site
+
+---
+
+### Option 2: Member Function Pointers
+
+**Implementation:**
+
+```cpp
+template<typename... Ts>
+class CallbackManager<void(Ts...)> {
+ private:
+  struct Callback {
+    void (*invoker)(void*, Ts...);  // 4 bytes
+    void* obj;                       // 4 bytes
+    // Total: 8 bytes
+  };
+
+  template<typename T, void (T::*Method)(Ts...)>
+  static void invoke_member(void* obj, Ts... args) {
+    (static_cast<T*>(obj)->*Method)(args...);
+  }
+
+  std::vector<Callback> callbacks_;
+
+ public:
+  // Register a member function
+  template<typename T, void (T::*Method)(Ts...)>
+  void add(T* obj) {
+    callbacks_.push_back({
+      &invoke_member<T, Method>,
+      obj
+    });
+  }
+
+  void call(Ts... args) {
+    for (auto& cb : callbacks_) {
+      cb.invoker(cb.obj, args...);
+    }
+  }
+
+  size_t size() const { return callbacks_.size(); }
+};
+```
+
+**Usage Changes:**
+
+```cpp
+// Add a method to BluetoothProxy
+void BluetoothProxy::on_scanner_state_changed(ScannerState state) {
+  if (this->api_connection_ != nullptr) {
+    this->send_bluetooth_scanner_state_(state);
+  }
+}
+
+// Register it
+parent_->add_scanner_state_callback<BluetoothProxy,
+                                     &BluetoothProxy::on_scanner_state_changed>(this);
+```
+
+**Savings:**
+- **Per callback:** 24 bytes (32 → 8)
+- **RAM saved:** 2.4 - 3.6 KB
+- **Flash saved:** ~5-10 KB
+
+**Pros:**
+- ✅ Same memory savings as Option 1
+- ✅ Most type-safe (member function pointers)
+- ✅ No static functions needed
+- ✅ Clean separation of callback logic
+
+**Cons:**
+- ❌ Verbose syntax at registration: `add<Type, &Type::method>(this)`
+- ❌ Requires adding methods to classes
+- ❌ Can't capture additional state beyond `this`
+- ❌ Template parameters at call site are ugly
+
+---
+
+### Option 3: Hybrid (Backward Compatible)
+
+**Implementation:**
+
+```cpp
+template<typename... Ts>
+class CallbackManager<void(Ts...)> {
+ private:
+  struct Callback {
+    void (*invoker)(void*, Ts...);  // 4 bytes
+    void* data;                      // 4 bytes
+    bool is_std_function;            // 1 byte + 3 padding = 4 bytes
+    // Total: 12 bytes
+  };
+
+  std::vector<Callback> callbacks_;
+
+ public:
+  // Optimized: function pointer + context
+  template<typename Context>
+  void add(void (*func)(Context*, Ts...), Context* context) {
+    callbacks_.push_back({
+      [](void* ctx, Ts... args) {
+        auto cb = static_cast<Callback*>(ctx);
+        auto typed_func = reinterpret_cast<void(*)(Context*, Ts...)>(cb->data);
+        auto typed_ctx = static_cast<Context*>(*reinterpret_cast<void**>(
+          static_cast<char*>(cb) + offsetof(Callback, data)
+        ));
+        typed_func(typed_ctx, args...);
+      },
+      reinterpret_cast<void*>(func),
+      false
+    });
+  }
+
+  // Legacy: std::function support (for gradual migration)
+  void add(std::function<void(Ts...)>&& func) {
+    auto* stored = new std::function<void(Ts...)>(std::move(func));
+    callbacks_.push_back({
+      [](void* ctx, Ts... args) {
+        (*static_cast<std::function<void(Ts...)>*>(ctx))(args...);
+      },
+      stored,
+      true
+    });
+  }
+
+  ~CallbackManager() {
+    for (auto& cb : callbacks_) {
+      if (cb.is_std_function) {
+        delete static_cast<std::function<void(Ts...)>*>(cb.data);
+      }
+    }
+  }
+
+  void call(Ts... args) {
+    for (auto& cb : callbacks_) {
+      cb.invoker(&cb, args...);
+    }
+  }
+
+  size_t size() const { return callbacks_.size(); }
+};
+```
+
+**Usage:**
+
+```cpp
+// NEW (optimized):
+parent_->add_scanner_state_callback(scanner_state_callback, this);
+
+// OLD (still works - gradual migration):
+parent_->add_scanner_state_callback([this](ScannerState state) {
+  // ... lambda still works
+});
+```
+
+**Savings:**
+- **Per optimized callback:** 20 bytes (32 → 12)
+- **Per legacy callback:** 0 bytes (still uses std::function)
+- **Allows gradual migration**
+
+**Pros:**
+- ✅ Backward compatible
+- ✅ Gradual migration path
+- ✅ Mix optimized and legacy in same codebase
+- ✅ No breaking changes
+
+**Cons:**
+- ❌ More complex implementation
+- ❌ Need to track which callbacks need cleanup
+- ❌ Extra bool field (padding makes it 12 bytes instead of 8)
+- ❌ std::function still compiled in
+
+---
+
+### Option 4: FixedVector (Keep std::function, Optimize Vector)
+
+**Implementation:**
+
+```cpp
+template<typename... Ts>
+class CallbackManager<void(Ts...)> {
+ public:
+  void add(std::function<void(Ts...)> &&callback) {
+    if (this->callbacks_.empty()) {
+      // Most CallbackManagers have 1-5 callbacks
+      this->callbacks_.init(5);
+    }
+    this->callbacks_.push_back(std::move(callback));
+  }
+
+  void call(Ts... args) {
+    for (auto &cb : this->callbacks_)
+      cb(args...);
+  }
+
+  size_t size() const { return this->callbacks_.size(); }
+
+ protected:
+  FixedVector<std::function<void(Ts...)>> callbacks_;  // Changed from std::vector
+};
+```
+
+**Savings:**
+- **Per callback:** 0 bytes (still 32 bytes)
+- **Per instance:** ~132 bytes (eliminates `_M_realloc_append`)
+- **Flash saved:** ~5-10 KB (one less vector template instantiation per type)
+- **Total:** ~132 bytes × ~20 unique callback types = ~2.6 KB
+
+**Pros:**
+- ✅ No API changes
+- ✅ Drop-in replacement
+- ✅ Eliminates vector reallocation machinery
+- ✅ Zero migration cost
+
+**Cons:**
+- ❌ No per-callback savings
+- ❌ std::function still 32 bytes each
+- ❌ Must guess max size at runtime
+- ❌ Can still overflow if guess is wrong
+
+---
+
+### Option 5: Template Parameter for Storage (Advanced)
+
+**Implementation:**
+
+```cpp
+enum class CallbackStorage {
+  FUNCTION,      // Use std::function (default, most flexible)
+  FUNCTION_PTR   // Use function pointer + context (optimal)
+};
+
+template<typename... Ts, CallbackStorage Storage = CallbackStorage::FUNCTION>
+class CallbackManager<void(Ts...)> {
+ // Specialize implementation based on Storage parameter
+};
+
+// Default: std::function (backward compatible)
+template<typename... Ts>
+class CallbackManager<void(Ts...), CallbackStorage::FUNCTION> {
+ protected:
+  std::vector<std::function<void(Ts...)>> callbacks_;
+  // ... current implementation
+};
+
+// Optimized: function pointer + context
+template<typename... Ts>
+class CallbackManager<void(Ts...), CallbackStorage::FUNCTION_PTR> {
+ private:
+  struct Callback {
+    void (*func)(void*, Ts...);
+    void* context;
+  };
+  std::vector<Callback> callbacks_;
+  // ... Option 1 implementation
+};
+```
+
+**Usage:**
+
+```cpp
+// Old components (no changes):
+CallbackManager<void(float)> callback_;  // Uses std::function by default
+
+// Optimized components:
+CallbackManager<void(ScannerState), CallbackStorage::FUNCTION_PTR> scanner_state_callbacks_;
+```
+
+**Savings:**
+- **Opt-in per component**
+- **Same as Option 1 for optimized components**
+
+**Pros:**
+- ✅ Gradual migration
+- ✅ No breaking changes
+- ✅ Explicit opt-in per component
+- ✅ Clear which components are optimized
+
+**Cons:**
+- ❌ Complex template metaprogramming
+- ❌ Two implementations to maintain
+- ❌ Template parameter pollution
+- ❌ Harder to understand codebase
+
+---
+
+## Comparison Matrix
+
+| Option | Per-Callback Savings | Flash Savings | API Changes | Complexity | Migration Cost |
+|--------|---------------------|---------------|-------------|------------|----------------|
+| **1. Function Ptr + Context** | **24 bytes** (75%) | **~10 KB** | Yes | Low | High (67 files) |
+| **2. Member Function Ptrs** | **24 bytes** (75%) | **~10 KB** | Yes | Medium | High + class changes |
+| **3. Hybrid** | **20 bytes** (opt-in) | **~8 KB** | No | High | Low (gradual) |
+| **4. FixedVector** | **0 bytes** | **~3 KB** | No | Low | None |
+| **5. Template Parameter** | **24 bytes** (opt-in) | **~10 KB** | Optional | High | Medium |
+
+---
+
+## Migration Effort Estimate
+
+### Option 1 (Function Pointer + Context)
+
+**Files to change:** ~67 files with CallbackManager usage
+
+**Per-file changes:**
+1. Convert lambda to static function (5 min)
+2. Update registration call (1 min)
+3. Test (5 min)
+
+**Estimate:** ~11 min × 67 files = **~12 hours** (assuming some files have multiple callbacks)
+
+**High-impact components to prioritize:**
+- `sensor.h` / `sensor.cpp` - many sensor callbacks
+- `esp32_ble_tracker.h` - BLE callbacks
+- `climate.h` - climate callbacks
+- `binary_sensor.h` - binary sensor callbacks
+
+### Option 4 (FixedVector)
+
+**Files to change:** 1 file (`esphome/core/helpers.h`)
+
+**Changes:**
+1. Change `std::vector` to `FixedVector` in CallbackManager
+2. Initialize with reasonable default size (e.g., 5)
+3. Test across codebase
+
+**Estimate:** **~1 hour**
+
+---
+
+## Recommendations
+
+### Immediate Action: Option 4 (FixedVector)
+
+**Why:**
+- Zero migration cost
+- Immediate ~3 KB flash savings
+- No API changes
+- Low risk
+
+**Implementation:**
+```cpp
+template<typename... Ts> class CallbackManager<void(Ts...)> {
+ public:
+  void add(std::function<void(Ts...)> &&callback) {
+    if (this->callbacks_.empty()) {
+      this->callbacks_.init(8);  // Most have < 8 callbacks
+    }
+    this->callbacks_.push_back(std::move(callback));
+  }
+  // ... rest unchanged
+ protected:
+  FixedVector<std::function<void(Ts...)>> callbacks_;
+};
+```
+
+### Long-term: Option 1 (Function Pointer + Context)
+
+**Why:**
+- Maximum savings (2.4-3.6 KB RAM + 10 KB flash)
+- Clean, simple implementation
+- Type-safe
+- Well-tested pattern
+
+**Migration Strategy:**
+1. Implement new `CallbackManager` in `helpers.h`
+2. Migrate high-impact components first:
+   - Core components (sensor, binary_sensor, climate)
+   - BLE components (esp32_ble_tracker, bluetooth_proxy)
+   - Network components (api, mqtt)
+3. Create helper macros to reduce boilerplate
+4. Migrate remaining components over 2-3 releases
+
+**Helper Macro Example:**
+```cpp
+// Define a callback wrapper
+#define CALLBACK_WRAPPER(Class, Method, ...) \
+  static void Method##_callback(Class* self, ##__VA_ARGS__) { \
+    self->Method(__VA_ARGS__); \
+  }
+
+// In class:
+class BluetoothProxy {
+  CALLBACK_WRAPPER(BluetoothProxy, on_scanner_state, ScannerState state)
+
+  void on_scanner_state(ScannerState state) {
+    // Implementation
+  }
+
+  void setup() {
+    parent_->add_scanner_state_callback(on_scanner_state_callback, this);
+  }
+};
+```
+
+---
+
+## Testing Plan
+
+### Phase 1: Unit Tests
+- Test CallbackManager with various signatures
+- Test multiple callbacks (1, 5, 10, 50)
+- Test callback removal/cancellation
+- Test edge cases (empty, nullptr, etc.)
+
+### Phase 2: Integration Tests
+- Create test YAML with heavily-used callbacks
+- Run on ESP32, ESP8266, RP2040
+- Measure before/after memory usage
+- Verify no functional regressions
+
+### Phase 3: Component Tests
+- Test high-impact components:
+  - sensor with multiple state callbacks
+  - esp32_improv with all automation triggers
+  - climate with state/control callbacks
+- Measure memory with `esphome analyze-memory`
+
+---
+
+## Risk Analysis
+
+### Option 1 Risks
+
+**Risk: Breaking change across 67 files**
+- **Mitigation:** Gradual rollout over 2-3 releases
+- **Mitigation:** Extensive testing on real hardware
+
+**Risk: Static function verbosity**
+- **Mitigation:** Helper macros (see above)
+- **Mitigation:** Code generation from Python
+
+**Risk: Missing captures**
+- **Mitigation:** Static analysis to find lambda captures
+- **Mitigation:** Compile-time errors for incorrect usage
+
+### Option 4 Risks
+
+**Risk: Buffer overflow if size guess is wrong**
+- **Mitigation:** Choose conservative default (8)
+- **Mitigation:** Add runtime warning on resize
+- **Mitigation:** Monitor in CI/testing
+
+**Risk: Still uses std::function (32 bytes each)**
+- **Mitigation:** Follow up with Option 1 migration
+- **Mitigation:** This is a stepping stone, not final solution
+
+---
+
+## Implementation Timeline
+
+### Week 1: Option 4 (Quick Win)
+- Implement FixedVector in CallbackManager
+- Test across codebase
+- Create PR with memory analysis
+- **Expected savings:** ~3 KB flash
+
+### Month 1-2: Option 1 (Core Components)
+- Implement function pointer CallbackManager
+- Migrate sensor, binary_sensor, climate
+- Create helper macros
+- **Expected savings:** ~1 KB RAM + 5 KB flash
+
+### Month 3-4: Option 1 (Remaining Components)
+- Migrate BLE components
+- Migrate network components (api, mqtt)
+- Migrate automation components
+- **Expected savings:** ~2 KB RAM + 10 KB flash total
+
+### Month 5: Cleanup
+- Remove std::function CallbackManager
+- Update documentation
+- Blog post about optimization
+
+---
+
+## Conclusion
+
+**Recommended Approach:**
+
+1. **Immediate (Week 1):** Implement Option 4 (FixedVector)
+   - Low risk, zero migration cost
+   - ~3 KB flash savings
+   - Sets foundation for Option 1
+
+2. **Short-term (Month 1-2):** Begin Option 1 migration
+   - Start with high-impact components
+   - ~1-2 KB RAM + 5 KB flash savings
+   - Validate approach
+
+3. **Long-term (Month 3-6):** Complete Option 1 migration
+   - Migrate all components
+   - ~3-4 KB total RAM + 10 KB flash savings
+   - Remove std::function variant
+
+**Total Expected Savings:**
+- **RAM:** 2.4 - 3.6 KB (75% reduction per callback)
+- **Flash:** 8 - 13 KB (vector overhead + template instantiations)
+- **Performance:** Slightly faster (no std::function indirection)
+
+This is significant for ESP8266 (80 KB RAM, 1 MB flash) and beneficial for all platforms.

callback_optimization_analysis.md

@@ -0,0 +1,75 @@
+# Callback Optimization Analysis - Why It Failed
+
+## Goal
+Convert stateful lambdas in CallbackManager to stateless function pointers to reduce flash usage.
+
+## Approach Tested
+
+### Attempt 1: Discriminated Union in CallbackManager
+**Changed:** `CallbackManager` to use union with discriminator (like `TemplatableValue`)
+- Stateless lambdas → function pointer (8 bytes)
+- Stateful lambdas → heap-allocated `std::function*` (8 bytes struct + 32 bytes heap)
+
+**Result:**
+- ❌ **+300 bytes heap usage** (37-38 callbacks × 8 bytes overhead)
+- ✅ Flash savings potential: ~200-400 bytes per stateless callback
+- **Verdict:** RAM is more precious than flash on ESP8266 - rejected
+
+### Attempt 2: Convert Individual Callbacks to Stateless
+**Changed:** API logger callback from `[this]` lambda to static member function
+- Used existing `global_api_server` pointer
+- Made callback stateless (convertible to function pointer)
+
+**Result:**
+```
+Removed:
+- Lambda _M_invoke: 103 bytes
+- Lambda _M_manager: 20 bytes
+
+Added:
+- log_callback function: 104 bytes
+- Function pointer _M_invoke: 20 bytes
+- Function pointer _M_manager: 20 bytes
+- Larger setup(): 7 bytes
+
+Net: +32 bytes flash ❌
+```
+
+**Why it failed:**
+Even though the callback became stateless, `CallbackManager` still uses `std::vector<std::function<void(Ts...)>>`. The function pointer STILL gets wrapped in `std::function`, generating the same template instantiation overhead. We just moved the code from a lambda to a static function.
+
+## Root Cause
+
+The optimization **requires BOTH**:
+1. ✅ Stateless callback (function pointer)
+2. ❌ Modified `CallbackManager` to store function pointers directly without `std::function` wrapper
+
+Without modifying `CallbackManager`, converting individual callbacks to function pointers provides **no benefit** and actually **increases** code size slightly due to the extra function definition.
+
+## Conclusion
+
+This optimization path is a **dead end** for ESPHome because:
+1. **Discriminated union approach**: Increases heap by 300 bytes (unacceptable for ESP8266)
+2. **Individual callback conversion**: Increases flash by 32+ bytes (no benefit without CallbackManager changes)
+
+The current `std::vector<std::function<...>>` approach is already optimal for the use case where most callbacks capture state.
+
+## Alternative Approaches Considered
+
+1. **Create separate `StatelessCallbackManager`**: Would require changing all call sites, not worth the complexity
+2. **Template parameter to select storage type**: Same issue - requires modifying many components
+3. **Hand-pick specific callbacks**: Provides no benefit as shown in Attempt 2
+
+## Recommendation
+
+**Do not pursue this optimization.** The RAM/flash trade-offs are unfavorable for embedded systems where RAM is typically more constrained than flash.
+
+---
+
+**Test Results:**
+- Platform: ESP8266-Arduino
+- Component: API
+- Result: +32 bytes flash (0.01% increase)
+- Status: Reverted
+
+🤖 Analysis by Claude Code

callback_optimization_implementation_plan.md

@@ -0,0 +1,256 @@
+# Callback Optimization Implementation Plan
+
+## Analysis Summary
+
+After Controller Registry (PR #11772), callback infrastructure can be further optimized:
+
+**Current overhead per entity (ESP32 32-bit):**
+- No callbacks: 16 bytes (4-byte ptr + 12-byte empty vector)
+- With callbacks: 32+ bytes (16 baseline + 16+ per callback)
+
+**Opportunity:** After Controller Registry, most entities have **zero callbacks** (API/WebServer use registry instead). We can save 12 bytes per entity by lazy allocation.
+
+## Entity Types by Callback Needs
+
+### Entities with ONLY filtered callbacks (most)
+- Climate, Fan, Light, Cover
+- Switch, Lock, Valve
+- Number, Select, Text, Button
+- AlarmControlPanel, MediaPlayer
+- BinarySensor, Event, Update, DateTime
+
+**Optimization:** Simple lazy-allocated vector
+
+### Entities with raw AND filtered callbacks
+- **Sensor** - has raw callbacks for automation triggers
+- **TextSensor** - has raw callbacks for automation triggers
+
+**Optimization:** Partitioned vector (filtered | raw)
+
+## Proposed Implementations
+
+### Option 1: Simple Lazy Vector (for entities without raw callbacks)
+
+```cpp
+class Climate {
+ protected:
+  std::unique_ptr<std::vector<std::function<void(Climate&)>>> state_callback_;
+};
+
+void Climate::add_on_state_callback(std::function<void(Climate&)> &&callback) {
+  if (!this->state_callback_) {
+    this->state_callback_ = std::make_unique<std::vector<std::function<void(Climate&)>>>();
+  }
+  this->state_callback_->push_back(std::move(callback));
+}
+
+void Climate::publish_state() {
+  if (this->state_callback_) {
+    for (auto &cb : *this->state_callback_) {
+      cb(*this);
+    }
+  }
+}
+```
+
+**Memory (ESP32):**
+- No callbacks: 4 bytes (saves 12 vs current)
+- 1 callback: 36 bytes (costs 4 vs current)
+- Net: Positive for API-only devices
+
+### Option 2: Partitioned Vector (for Sensor & TextSensor)
+
+```cpp
+class Sensor {
+ protected:
+  struct Callbacks {
+    std::vector<std::function<void(float)>> callbacks_;
+    uint8_t filtered_count_{0};  // Partition point: [filtered | raw]
+
+    void add_filtered(std::function<void(float)> &&fn) {
+      callbacks_.push_back(std::move(fn));
+      if (filtered_count_ < callbacks_.size() - 1) {
+        std::swap(callbacks_[filtered_count_], callbacks_[callbacks_.size() - 1]);
+      }
+      filtered_count_++;
+    }
+
+    void add_raw(std::function<void(float)> &&fn) {
+      callbacks_.push_back(std::move(fn));  // Append to raw section
+    }
+
+    void call_filtered(float value) {
+      for (size_t i = 0; i < filtered_count_; i++) {
+        callbacks_[i](value);
+      }
+    }
+
+    void call_raw(float value) {
+      for (size_t i = filtered_count_; i < callbacks_.size(); i++) {
+        callbacks_[i](value);
+      }
+    }
+  };
+
+  std::unique_ptr<Callbacks> callbacks_;
+};
+```
+
+**Why partitioned:**
+- Maintains separation of raw (pre-filter) vs filtered (post-filter) callbacks
+- O(1) insertion via swap (order doesn't matter)
+- No branching in hot path
+- Saves 12 bytes when no callbacks
+
+## Memory Impact Analysis
+
+### Scenario 1: API-only device (10 sensors, no MQTT, no automations)
+**Current:** 10 × 16 = 160 bytes
+**Optimized:** 10 × 4 = 40 bytes
+**Saves: 120 bytes** ✅
+
+### Scenario 2: MQTT-enabled device (10 sensors with MQTT)
+**Current:** 10 × 32 = 320 bytes
+**Optimized:** 10 × 36 = 360 bytes
+**Costs: 40 bytes** ⚠️
+
+### Scenario 3: Mixed device (5 API-only + 5 MQTT)
+**Current:** (5 × 16) + (5 × 32) = 240 bytes
+**Optimized:** (5 × 4) + (5 × 36) = 200 bytes
+**Saves: 40 bytes** ✅
+
+### Scenario 4: Sensor with automation (1 raw + 1 filtered)
+**Current:** 16 + 12 + 16 + 16 = 60 bytes
+**Optimized:** 4 + 16 + 32 = 52 bytes
+**Saves: 8 bytes** ✅
+
+## Implementation Strategy
+
+### Phase 1: Simple Entities (high impact, low complexity)
+1. **Climate** (common, no raw callbacks)
+2. **Fan** (common, no raw callbacks)
+3. **Cover** (common, no raw callbacks)
+4. **Switch** (very common, no raw callbacks)
+5. **Lock** (no raw callbacks)
+
+**Change:** Replace `CallbackManager<void(...)> callback_` with `std::unique_ptr<std::vector<std::function<...>>>`
+
+### Phase 2: Sensor & TextSensor (more complex)
+1. **Sensor** (most common entity, has raw callbacks)
+2. **TextSensor** (common, has raw callbacks)
+
+**Change:** Implement partitioned vector approach
+
+### Phase 3: Remaining Entities
+- BinarySensor, Number, Select, Text
+- Light, Valve, AlarmControlPanel
+- MediaPlayer, Button, Event, Update, DateTime
+
+**Change:** Simple lazy vector
+
+## Code Template for Simple Entities
+
+```cpp
+// Header (.h)
+class EntityType {
+ public:
+  void add_on_state_callback(std::function<void(Args...)> &&callback);
+
+ protected:
+  std::unique_ptr<std::vector<std::function<void(Args...)>>> state_callback_;
+};
+
+// Implementation (.cpp)
+void EntityType::add_on_state_callback(std::function<void(Args...)> &&callback) {
+  if (!this->state_callback_) {
+    this->state_callback_ = std::make_unique<std::vector<std::function<void(Args...)>>>();
+  }
+  this->state_callback_->push_back(std::move(callback));
+}
+
+void EntityType::publish_state(...) {
+  // ... state update logic ...
+
+  if (this->state_callback_) {
+    for (auto &cb : *this->state_callback_) {
+      cb(...);
+    }
+  }
+
+#ifdef USE_CONTROLLER_REGISTRY
+  ControllerRegistry::notify_entity_update(this);
+#endif
+}
+```
+
+## Testing Strategy
+
+1. **Unit tests:** Verify callback ordering/execution unchanged
+2. **Integration tests:** Test with MQTT, automations, copy components
+3. **Memory benchmarks:** Measure actual flash/RAM impact
+4. **Compatibility:** Ensure no API breakage
+
+## Expected Results
+
+**For typical ESPHome devices after Controller Registry:**
+- Most entities: API/WebServer only (no callbacks)
+- Some entities: MQTT (1 callback)
+- Few entities: Automations (1-2 callbacks)
+
+**Memory savings:**
+- Device with 20 entities, 5 with MQTT: ~180 bytes saved
+- Device with 50 entities, 10 with MQTT: ~480 bytes saved
+
+**Trade-off:**
+- Entities without callbacks: Save 12 bytes ✅
+- Entities with callbacks: Cost 4 bytes ⚠️
+- Net benefit: Positive for most devices
+
+## Risks & Mitigation
+
+**Risk 1:** Increased complexity
+- **Mitigation:** Start with simple entities first, template for reuse
+
+**Risk 2:** Performance regression
+- **Mitigation:** Minimal - just nullptr check (likely free with branch prediction)
+
+**Risk 3:** Edge cases with callback order
+- **Mitigation:** Order already undefined within same callback type
+
+## Open Questions
+
+1. Should we template the Callbacks struct for reuse across entity types?
+2. Should Phase 1 include a memory benchmark before expanding?
+3. Should we make this configurable (compile-time flag)?
+
+## Files Modified
+
+### Phase 1 (Simple Entities)
+- `esphome/components/climate/climate.h`
+- `esphome/components/climate/climate.cpp`
+- `esphome/components/fan/fan.h`
+- `esphome/components/fan/fan.cpp`
+- `esphome/components/cover/cover.h`
+- `esphome/components/cover/cover.cpp`
+- (etc. for switch, lock)
+
+### Phase 2 (Partitioned)
+- `esphome/components/sensor/sensor.h`
+- `esphome/components/sensor/sensor.cpp`
+- `esphome/components/text_sensor/text_sensor.h`
+- `esphome/components/text_sensor/text_sensor.cpp`
+
+### Phase 3 (Remaining)
+- All other entity types
+
+## Conclusion
+
+**Recommendation: Implement in phases**
+
+1. Start with Climate (common entity, simple change)
+2. Measure impact on real device
+3. If positive, proceed with other simple entities
+4. Implement partitioned approach for Sensor/TextSensor
+5. Complete remaining entity types
+
+Expected net savings: **50-500 bytes per typical device**, depending on entity count and MQTT usage.

callback_usage_analysis.md

@@ -0,0 +1,118 @@
+# add_on_state_callback Usage Analysis
+
+## Summary
+
+After the Controller Registry migration (PR #11772), `add_on_state_callback` is still widely used in the codebase, but for **legitimate reasons** - components that genuinely need per-entity state tracking.
+
+## Usage Breakdown
+
+### 1. **MQTT Components** (~17 uses)
+**Purpose:** Per-entity MQTT configuration requires callbacks
+- Each MQTT component instance needs to publish to custom topics with custom QoS/retain settings
+- Cannot use Controller pattern due to per-entity configuration overhead
+- Examples: `mqtt_sensor.cpp`, `mqtt_climate.cpp`, `mqtt_number.cpp`, etc.
+
+```cpp
+this->sensor_->add_on_state_callback([this](float state) {
+  this->publish_state(state);
+});
+```
+
+### 2. **Copy Components** (~10 uses)
+**Purpose:** Mirror state from one entity to another
+- Each copy instance tracks a different source entity
+- Legitimate use of callbacks for entity-to-entity synchronization
+- Examples: `copy_sensor.cpp`, `copy_fan.cpp`, `copy_select.cpp`, etc.
+
+```cpp
+source_->add_on_state_callback([this](const std::string &value) {
+  this->publish_state(value);
+});
+```
+
+### 3. **Derivative Sensors** (~5-7 uses)
+**Purpose:** Compute derived values from source sensors
+- **integration_sensor:** Integrates sensor values over time
+- **total_daily_energy:** Tracks cumulative energy
+- **combination:** Combines multiple sensor values
+- **graph:** Samples sensor data for display
+- **duty_time:** Tracks on-time duration
+- **ntc/absolute_humidity/resistance:** Mathematical transformations
+
+```cpp
+this->sensor_->add_on_state_callback([this](float state) {
+  this->process_sensor_value_(state);
+});
+```
+
+### 4. **Climate/Cover with Sensors** (~10-15 uses)
+**Purpose:** External sensors providing feedback to control loops
+- **feedback_cover:** Binary sensors for open/close/obstacle detection
+- **bang_bang/pid/thermostat:** External temperature sensors for climate control
+- **climate_ir (toshiba/yashima/heatpumpir):** Temperature sensors for IR climate
+
+```cpp
+this->sensor_->add_on_state_callback([this](float state) {
+  this->current_temperature = state;
+  // Trigger control loop update
+});
+```
+
+### 5. **Entity Base Classes** (~10-15 definitions)
+**Purpose:** Provide the callback interface for all entities
+- Not actual usage, just the method definitions
+- Examples: `sensor.cpp::add_on_state_callback()`, `climate.cpp::add_on_state_callback()`, etc.
+
+### 6. **Automation Trigger Classes** (~15-20 definitions)
+**Purpose:** User-defined YAML automations need callbacks
+- Files like `sensor/automation.h`, `climate/automation.h`
+- Implement triggers like `on_value:`, `on_state:`
+- Cannot be migrated - this is user-facing automation functionality
+
+### 7. **Miscellaneous** (~5-10 uses)
+- **voice_assistant/micro_wake_word:** State coordination
+- **esp32_improv:** Provisioning state tracking
+- **http_request/update:** Update status monitoring
+- **switch/binary_sensor:** Cross-component dependencies
+- **OTA callbacks:** OTA state monitoring
+
+## Key Insights
+
+### What's NOT Using Callbacks Anymore ✅
+**API Server and WebServer** - migrated to Controller Registry
+- **Before:** Each entity had 2 callbacks (API + WebServer) = ~32 bytes overhead
+- **After:** Zero per-entity overhead = saves ~32 bytes per entity
+
+### What SHOULD Keep Using Callbacks ✅
+All the above categories have legitimate reasons:
+
+1. **Per-entity configuration:** MQTT needs custom topics/QoS per entity
+2. **Entity-to-entity relationships:** Copy components, derivative sensors
+3. **Control loop feedback:** Climate/cover with external sensors
+4. **User-defined automations:** YAML triggers configured by users
+5. **Component dependencies:** Components that genuinely depend on other entities
+
+## Memory Impact
+
+**Per Sensor (ESP32):**
+- Empty callback infrastructure: **~16 bytes** (unique_ptr + empty vector)
+- With one callback (e.g., MQTT): **~32 bytes** (16 + std::function)
+- With multiple callbacks: **~32 + 16n bytes** (where n = additional callbacks)
+
+**Typical scenarios:**
+- Sensor with **only API/WebServer:** ~16 bytes (no callbacks registered)
+- Sensor with **MQTT:** ~32 bytes (one callback)
+- Sensor with **MQTT + automation:** ~48 bytes (two callbacks)
+- Sensor with **copy + total_daily_energy + graph:** ~64 bytes (three callbacks)
+
+## Conclusion
+
+The callback system is still heavily used (~103 occurrences) but for **appropriate reasons**:
+- Components with per-entity state/configuration (MQTT, Copy)
+- Sensor processing chains (derivatives, transformations)
+- Control loops with external feedback (climate, covers)
+- User-defined automations (cannot be removed)
+
+The Controller Registry successfully eliminated wasteful callbacks for **stateless global handlers** (API/WebServer), saving ~32 bytes per entity for those use cases.
+
+**No further callback elimination opportunities** exist without fundamentally changing ESPHome's architecture or breaking user-facing features.

esphome/__main__.py

@@ -62,6 +62,40 @@ from esphome.util import (
 
 _LOGGER = logging.getLogger(__name__)
 
+# Special non-component keys that appear in configs
+_NON_COMPONENT_KEYS = frozenset(
+    {
+        CONF_ESPHOME,
+        "substitutions",
+        "packages",
+        "globals",
+        "external_components",
+        "<<",
+    }
+)
+
+
+def detect_external_components(config: ConfigType) -> set[str]:
+    """Detect external/custom components in the configuration.
+
+    External components are those that appear in the config but are not
+    part of ESPHome's built-in components and are not special config keys.
+
+    Args:
+        config: The ESPHome configuration dictionary
+
+    Returns:
+        A set of external component names
+    """
+    from esphome.analyze_memory.helpers import get_esphome_components
+
+    builtin_components = get_esphome_components()
+    return {
+        key
+        for key in config
+        if key not in builtin_components and key not in _NON_COMPONENT_KEYS
+    }
+
 
 class ArgsProtocol(Protocol):
     device: list[str] | None
@@ -117,6 +151,17 @@ class Purpose(StrEnum):
     LOGGING = "logging"
 
 
+class PortType(StrEnum):
+    SERIAL = "SERIAL"
+    NETWORK = "NETWORK"
+    MQTT = "MQTT"
+    MQTTIP = "MQTTIP"
+
+
+# Magic MQTT port types that require special handling
+_MQTT_PORT_TYPES = frozenset({PortType.MQTT, PortType.MQTTIP})
+
+
 def _resolve_with_cache(address: str, purpose: Purpose) -> list[str]:
     """Resolve an address using cache if available, otherwise return the address itself."""
     if CORE.address_cache and (cached := CORE.address_cache.get_addresses(address)):
@@ -162,19 +207,21 @@ def choose_upload_log_host(
                     if has_mqtt_logging():
                         resolved.append("MQTT")
 
-                    if has_api() and has_non_ip_address():
+                    if has_api() and has_non_ip_address() and has_resolvable_address():
                         resolved.extend(_resolve_with_cache(CORE.address, purpose))
 
                 elif purpose == Purpose.UPLOADING:
                     if has_ota() and has_mqtt_ip_lookup():
                         resolved.append("MQTTIP")
 
-                    if has_ota() and has_non_ip_address():
+                    if has_ota() and has_non_ip_address() and has_resolvable_address():
                         resolved.extend(_resolve_with_cache(CORE.address, purpose))
             else:
                 resolved.append(device)
         if not resolved:
-            _LOGGER.error("All specified devices: %s could not be resolved.", defaults)
+            raise EsphomeError(
+                f"All specified devices {defaults} could not be resolved. Is the device connected to the network?"
+            )
         return resolved
 
     # No devices specified, show interactive chooser
@@ -268,8 +315,20 @@ def has_ip_address() -> bool:
 
 
 def has_resolvable_address() -> bool:
-    """Check if CORE.address is resolvable (via mDNS or is an IP address)."""
-    return has_mdns() or has_ip_address()
+    """Check if CORE.address is resolvable (via mDNS, DNS, or is an IP address)."""
+    # Any address (IP, mDNS hostname, or regular DNS hostname) is resolvable
+    # The resolve_ip_address() function in helpers.py handles all types via AsyncResolver
+    if CORE.address is None:
+        return False
+
+    if has_ip_address():
+        return True
+
+    if has_mdns():
+        return True
+
+    # .local mDNS hostnames are only resolvable if mDNS is enabled
+    return not CORE.address.endswith(".local")
 
 
 def mqtt_get_ip(config: ConfigType, username: str, password: str, client_id: str):
@@ -278,16 +337,67 @@ def mqtt_get_ip(config: ConfigType, username: str, password: str, client_id: str
     return mqtt.get_esphome_device_ip(config, username, password, client_id)
 
 
-_PORT_TO_PORT_TYPE = {
-    "MQTT": "MQTT",
-    "MQTTIP": "MQTTIP",
-}
+def _resolve_network_devices(
+    devices: list[str], config: ConfigType, args: ArgsProtocol
+) -> list[str]:
+    """Resolve device list, converting MQTT magic strings to actual IP addresses.
+
+    This function filters the devices list to:
+    - Replace MQTT/MQTTIP magic strings with actual IP addresses via MQTT lookup
+    - Deduplicate addresses while preserving order
+    - Only resolve MQTT once even if multiple MQTT strings are present
+    - If MQTT resolution fails, log a warning and continue with other devices
+
+    Args:
+        devices: List of device identifiers (IPs, hostnames, or magic strings)
+        config: ESPHome configuration
+        args: Command-line arguments containing MQTT credentials
+
+    Returns:
+        List of network addresses suitable for connection attempts
+    """
+    network_devices: list[str] = []
+    mqtt_resolved: bool = False
+
+    for device in devices:
+        port_type = get_port_type(device)
+        if port_type in _MQTT_PORT_TYPES:
+            # Only resolve MQTT once, even if multiple MQTT entries
+            if not mqtt_resolved:
+                try:
+                    mqtt_ips = mqtt_get_ip(
+                        config, args.username, args.password, args.client_id
+                    )
+                    network_devices.extend(mqtt_ips)
+                except EsphomeError as err:
+                    _LOGGER.warning(
+                        "MQTT IP discovery failed (%s), will try other devices if available",
+                        err,
+                    )
+                mqtt_resolved = True
+        elif device not in network_devices:
+            # Regular network address or IP - add if not already present
+            network_devices.append(device)
+
+    return network_devices
 
 
-def get_port_type(port: str) -> str:
+def get_port_type(port: str) -> PortType:
+    """Determine the type of port/device identifier.
+
+    Returns:
+        PortType.SERIAL for serial ports (/dev/ttyUSB0, COM1, etc.)
+        PortType.MQTT for MQTT logging
+        PortType.MQTTIP for MQTT IP lookup
+        PortType.NETWORK for IP addresses, hostnames, or mDNS names
+    """
     if port.startswith("/") or port.startswith("COM"):
-        return "SERIAL"
-    return _PORT_TO_PORT_TYPE.get(port, "NETWORK")
+        return PortType.SERIAL
+    if port == "MQTT":
+        return PortType.MQTT
+    if port == "MQTTIP":
+        return PortType.MQTTIP
+    return PortType.NETWORK
 
 
 def run_miniterm(config: ConfigType, port: str, args) -> int:
@@ -402,7 +512,9 @@ def write_cpp_file() -> int:
 def compile_program(args: ArgsProtocol, config: ConfigType) -> int:
     from esphome import platformio_api
 
-    _LOGGER.info("Compiling app...")
+    # NOTE: "Build path:" format is parsed by script/ci_memory_impact_extract.py
+    # If you change this format, update the regex in that script as well
+    _LOGGER.info("Compiling app... Build path: %s", CORE.build_path)
     rc = platformio_api.run_compile(config, CORE.verbose)
     if rc != 0:
         return rc
@@ -487,7 +599,7 @@ def upload_using_platformio(config: ConfigType, port: str):
 
 
 def check_permissions(port: str):
-    if os.name == "posix" and get_port_type(port) == "SERIAL":
+    if os.name == "posix" and get_port_type(port) == PortType.SERIAL:
         # Check if we can open selected serial port
         if not os.access(port, os.F_OK):
             raise EsphomeError(
@@ -515,7 +627,7 @@ def upload_program(
     except AttributeError:
         pass
 
-    if get_port_type(host) == "SERIAL":
+    if get_port_type(host) == PortType.SERIAL:
         check_permissions(host)
 
         exit_code = 1
@@ -542,17 +654,16 @@ def upload_program(
     from esphome import espota2
 
     remote_port = int(ota_conf[CONF_PORT])
-    password = ota_conf.get(CONF_PASSWORD, "")
+    password = ota_conf.get(CONF_PASSWORD)
     if getattr(args, "file", None) is not None:
         binary = Path(args.file)
     else:
         binary = CORE.firmware_bin
 
-    # MQTT address resolution
-    if get_port_type(host) in ("MQTT", "MQTTIP"):
-        devices = mqtt_get_ip(config, args.username, args.password, args.client_id)
+    # Resolve MQTT magic strings to actual IP addresses
+    network_devices = _resolve_network_devices(devices, config, args)
 
-    return espota2.run_ota(devices, remote_port, password, binary)
+    return espota2.run_ota(network_devices, remote_port, password, binary)
 
 
 def show_logs(config: ConfigType, args: ArgsProtocol, devices: list[str]) -> int | None:
@@ -567,32 +678,22 @@ def show_logs(config: ConfigType, args: ArgsProtocol, devices: list[str]) -> int
         raise EsphomeError("Logger is not configured!")
 
     port = devices[0]
+    port_type = get_port_type(port)
 
-    if get_port_type(port) == "SERIAL":
+    if port_type == PortType.SERIAL:
         check_permissions(port)
         return run_miniterm(config, port, args)
 
-    port_type = get_port_type(port)
-
     # Check if we should use API for logging
-    if has_api():
-        addresses_to_use: list[str] | None = None
+    # Resolve MQTT magic strings to actual IP addresses
+    if has_api() and (
+        network_devices := _resolve_network_devices(devices, config, args)
+    ):
+        from esphome.components.api.client import run_logs
 
-        if port_type == "NETWORK" and (has_mdns() or is_ip_address(port)):
-            addresses_to_use = devices
-        elif port_type in ("NETWORK", "MQTT", "MQTTIP") and has_mqtt_ip_lookup():
-            # Only use MQTT IP lookup if the first condition didn't match
-            # (for MQTT/MQTTIP types, or for NETWORK when mdns/ip check fails)
-            addresses_to_use = mqtt_get_ip(
-                config, args.username, args.password, args.client_id
-            )
+        return run_logs(config, network_devices)
 
-        if addresses_to_use is not None:
-            from esphome.components.api.client import run_logs
-
-            return run_logs(config, addresses_to_use)
-
-    if port_type in ("NETWORK", "MQTT") and has_mqtt_logging():
+    if port_type in (PortType.NETWORK, PortType.MQTT) and has_mqtt_logging():
         from esphome import mqtt
 
         return mqtt.show_logs(
@@ -835,6 +936,54 @@ def command_idedata(args: ArgsProtocol, config: ConfigType) -> int:
     return 0
 
 
+def command_analyze_memory(args: ArgsProtocol, config: ConfigType) -> int:
+    """Analyze memory usage by component.
+
+    This command compiles the configuration and performs memory analysis.
+    Compilation is fast if sources haven't changed (just relinking).
+    """
+    from esphome import platformio_api
+    from esphome.analyze_memory.cli import MemoryAnalyzerCLI
+
+    # Always compile to ensure fresh data (fast if no changes - just relinks)
+    exit_code = write_cpp(config)
+    if exit_code != 0:
+        return exit_code
+    exit_code = compile_program(args, config)
+    if exit_code != 0:
+        return exit_code
+    _LOGGER.info("Successfully compiled program.")
+
+    # Get idedata for analysis
+    idedata = platformio_api.get_idedata(config)
+    if idedata is None:
+        _LOGGER.error("Failed to get IDE data for memory analysis")
+        return 1
+
+    firmware_elf = Path(idedata.firmware_elf_path)
+
+    # Extract external components from config
+    external_components = detect_external_components(config)
+    _LOGGER.debug("Detected external components: %s", external_components)
+
+    # Perform memory analysis
+    _LOGGER.info("Analyzing memory usage...")
+    analyzer = MemoryAnalyzerCLI(
+        str(firmware_elf),
+        idedata.objdump_path,
+        idedata.readelf_path,
+        external_components,
+    )
+    analyzer.analyze()
+
+    # Generate and display report
+    report = analyzer.generate_report()
+    print()
+    print(report)
+
+    return 0
+
+
 def command_rename(args: ArgsProtocol, config: ConfigType) -> int | None:
     new_name = args.name
     for c in new_name:
@@ -950,6 +1099,7 @@ POST_CONFIG_ACTIONS = {
     "idedata": command_idedata,
     "rename": command_rename,
     "discover": command_discover,
+    "analyze-memory": command_analyze_memory,
 }
 
 SIMPLE_CONFIG_ACTIONS = [
@@ -1002,6 +1152,12 @@ def parse_args(argv):
         action="append",
         default=[],
     )
+    options_parser.add_argument(
+        "--testing-mode",
+        help="Enable testing mode (disables validation checks for grouped component testing)",
+        action="store_true",
+        default=False,
+    )
 
     parser = argparse.ArgumentParser(
         description=f"ESPHome {const.__version__}", parents=[options_parser]
@@ -1229,6 +1385,14 @@ def parse_args(argv):
     )
     parser_rename.add_argument("name", help="The new name for the device.", type=str)
 
+    parser_analyze_memory = subparsers.add_parser(
+        "analyze-memory",
+        help="Analyze memory usage by component.",
+    )
+    parser_analyze_memory.add_argument(
+        "configuration", help="Your YAML configuration file(s).", nargs="+"
+    )
+
     # Keep backward compatibility with the old command line format of
     # esphome <config> <command>.
     #
@@ -1260,6 +1424,7 @@ def run_esphome(argv):
 
     args = parse_args(argv)
     CORE.dashboard = args.dashboard
+    CORE.testing_mode = args.testing_mode
 
     # Create address cache from command-line arguments
     CORE.address_cache = AddressCache.from_cli_args(

esphome/analyze_memory/__init__.py

@@ -0,0 +1,502 @@
+"""Memory usage analyzer for ESPHome compiled binaries."""
+
+from collections import defaultdict
+from dataclasses import dataclass, field
+import logging
+from pathlib import Path
+import re
+import subprocess
+from typing import TYPE_CHECKING
+
+from .const import (
+    CORE_SUBCATEGORY_PATTERNS,
+    DEMANGLED_PATTERNS,
+    ESPHOME_COMPONENT_PATTERN,
+    SECTION_TO_ATTR,
+    SYMBOL_PATTERNS,
+)
+from .helpers import (
+    get_component_class_patterns,
+    get_esphome_components,
+    map_section_name,
+    parse_symbol_line,
+)
+
+if TYPE_CHECKING:
+    from esphome.platformio_api import IDEData
+
+_LOGGER = logging.getLogger(__name__)
+
+# GCC global constructor/destructor prefix annotations
+_GCC_PREFIX_ANNOTATIONS = {
+    "_GLOBAL__sub_I_": "global constructor for",
+    "_GLOBAL__sub_D_": "global destructor for",
+}
+
+# GCC optimization suffix pattern (e.g., $isra$0, $part$1, $constprop$2)
+_GCC_OPTIMIZATION_SUFFIX_PATTERN = re.compile(r"(\$(?:isra|part|constprop)\$\d+)")
+
+# C++ runtime patterns for categorization
+_CPP_RUNTIME_PATTERNS = frozenset(["vtable", "typeinfo", "thunk"])
+
+# libc printf/scanf family base names (used to detect variants like _printf_r, vfprintf, etc.)
+_LIBC_PRINTF_SCANF_FAMILY = frozenset(["printf", "fprintf", "sprintf", "scanf"])
+
+# Regex pattern for parsing readelf section headers
+# Format: [ #] name type addr off size
+_READELF_SECTION_PATTERN = re.compile(
+    r"\s*\[\s*\d+\]\s+([\.\w]+)\s+\w+\s+[\da-fA-F]+\s+[\da-fA-F]+\s+([\da-fA-F]+)"
+)
+
+# Component category prefixes
+_COMPONENT_PREFIX_ESPHOME = "[esphome]"
+_COMPONENT_PREFIX_EXTERNAL = "[external]"
+_COMPONENT_CORE = f"{_COMPONENT_PREFIX_ESPHOME}core"
+_COMPONENT_API = f"{_COMPONENT_PREFIX_ESPHOME}api"
+
+# C++ namespace prefixes
+_NAMESPACE_ESPHOME = "esphome::"
+_NAMESPACE_STD = "std::"
+
+# Type alias for symbol information: (symbol_name, size, component)
+SymbolInfoType = tuple[str, int, str]
+
+
+@dataclass
+class MemorySection:
+    """Represents a memory section with its symbols."""
+
+    name: str
+    symbols: list[SymbolInfoType] = field(default_factory=list)
+    total_size: int = 0
+
+
+@dataclass
+class ComponentMemory:
+    """Tracks memory usage for a component."""
+
+    name: str
+    text_size: int = 0  # Code in flash
+    rodata_size: int = 0  # Read-only data in flash
+    data_size: int = 0  # Initialized data (flash + ram)
+    bss_size: int = 0  # Uninitialized data (ram only)
+    symbol_count: int = 0
+
+    @property
+    def flash_total(self) -> int:
+        """Total flash usage (text + rodata + data)."""
+        return self.text_size + self.rodata_size + self.data_size
+
+    @property
+    def ram_total(self) -> int:
+        """Total RAM usage (data + bss)."""
+        return self.data_size + self.bss_size
+
+
+class MemoryAnalyzer:
+    """Analyzes memory usage from ELF files."""
+
+    def __init__(
+        self,
+        elf_path: str,
+        objdump_path: str | None = None,
+        readelf_path: str | None = None,
+        external_components: set[str] | None = None,
+        idedata: "IDEData | None" = None,
+    ) -> None:
+        """Initialize memory analyzer.
+
+        Args:
+            elf_path: Path to ELF file to analyze
+            objdump_path: Path to objdump binary (auto-detected from idedata if not provided)
+            readelf_path: Path to readelf binary (auto-detected from idedata if not provided)
+            external_components: Set of external component names
+            idedata: Optional PlatformIO IDEData object to auto-detect toolchain paths
+        """
+        self.elf_path = Path(elf_path)
+        if not self.elf_path.exists():
+            raise FileNotFoundError(f"ELF file not found: {elf_path}")
+
+        # Auto-detect toolchain paths from idedata if not provided
+        if idedata is not None and (objdump_path is None or readelf_path is None):
+            objdump_path = objdump_path or idedata.objdump_path
+            readelf_path = readelf_path or idedata.readelf_path
+            _LOGGER.debug("Using toolchain paths from PlatformIO idedata")
+
+        self.objdump_path = objdump_path or "objdump"
+        self.readelf_path = readelf_path or "readelf"
+        self.external_components = external_components or set()
+
+        self.sections: dict[str, MemorySection] = {}
+        self.components: dict[str, ComponentMemory] = defaultdict(
+            lambda: ComponentMemory("")
+        )
+        self._demangle_cache: dict[str, str] = {}
+        self._uncategorized_symbols: list[tuple[str, str, int]] = []
+        self._esphome_core_symbols: list[
+            tuple[str, str, int]
+        ] = []  # Track core symbols
+        self._component_symbols: dict[str, list[tuple[str, str, int]]] = defaultdict(
+            list
+        )  # Track symbols for all components
+
+    def analyze(self) -> dict[str, ComponentMemory]:
+        """Analyze the ELF file and return component memory usage."""
+        self._parse_sections()
+        self._parse_symbols()
+        self._categorize_symbols()
+        return dict(self.components)
+
+    def _parse_sections(self) -> None:
+        """Parse section headers from ELF file."""
+        result = subprocess.run(
+            [self.readelf_path, "-S", str(self.elf_path)],
+            capture_output=True,
+            text=True,
+            check=True,
+        )
+
+        # Parse section headers
+        for line in result.stdout.splitlines():
+            # Look for section entries
+            if not (match := _READELF_SECTION_PATTERN.match(line)):
+                continue
+
+            section_name = match.group(1)
+            size_hex = match.group(2)
+            size = int(size_hex, 16)
+
+            # Map to standard section name
+            mapped_section = map_section_name(section_name)
+            if not mapped_section:
+                continue
+
+            if mapped_section not in self.sections:
+                self.sections[mapped_section] = MemorySection(mapped_section)
+            self.sections[mapped_section].total_size += size
+
+    def _parse_symbols(self) -> None:
+        """Parse symbols from ELF file."""
+        result = subprocess.run(
+            [self.objdump_path, "-t", str(self.elf_path)],
+            capture_output=True,
+            text=True,
+            check=True,
+        )
+
+        # Track seen addresses to avoid duplicates
+        seen_addresses: set[str] = set()
+
+        for line in result.stdout.splitlines():
+            if not (symbol_info := parse_symbol_line(line)):
+                continue
+
+            section, name, size, address = symbol_info
+
+            # Skip duplicate symbols at the same address (e.g., C1/C2 constructors)
+            if address in seen_addresses or section not in self.sections:
+                continue
+
+            self.sections[section].symbols.append((name, size, ""))
+            seen_addresses.add(address)
+
+    def _categorize_symbols(self) -> None:
+        """Categorize symbols by component."""
+        # First, collect all unique symbol names for batch demangling
+        all_symbols = {
+            symbol_name
+            for section in self.sections.values()
+            for symbol_name, _, _ in section.symbols
+        }
+
+        # Batch demangle all symbols at once
+        self._batch_demangle_symbols(list(all_symbols))
+
+        # Now categorize with cached demangled names
+        for section_name, section in self.sections.items():
+            for symbol_name, size, _ in section.symbols:
+                component = self._identify_component(symbol_name)
+
+                if component not in self.components:
+                    self.components[component] = ComponentMemory(component)
+
+                comp_mem = self.components[component]
+                comp_mem.symbol_count += 1
+
+                # Update the appropriate size attribute based on section
+                if attr_name := SECTION_TO_ATTR.get(section_name):
+                    setattr(comp_mem, attr_name, getattr(comp_mem, attr_name) + size)
+
+                # Track uncategorized symbols
+                if component == "other" and size > 0:
+                    demangled = self._demangle_symbol(symbol_name)
+                    self._uncategorized_symbols.append((symbol_name, demangled, size))
+
+                # Track ESPHome core symbols for detailed analysis
+                if component == _COMPONENT_CORE and size > 0:
+                    demangled = self._demangle_symbol(symbol_name)
+                    self._esphome_core_symbols.append((symbol_name, demangled, size))
+
+                # Track all component symbols for detailed analysis
+                if size > 0:
+                    demangled = self._demangle_symbol(symbol_name)
+                    self._component_symbols[component].append(
+                        (symbol_name, demangled, size)
+                    )
+
+    def _identify_component(self, symbol_name: str) -> str:
+        """Identify which component a symbol belongs to."""
+        # Demangle C++ names if needed
+        demangled = self._demangle_symbol(symbol_name)
+
+        # Check for special component classes first (before namespace pattern)
+        # This handles cases like esphome::ESPHomeOTAComponent which should map to ota
+        if _NAMESPACE_ESPHOME in demangled:
+            # Check for special component classes that include component name in the class
+            # For example: esphome::ESPHomeOTAComponent -> ota component
+            for component_name in get_esphome_components():
+                patterns = get_component_class_patterns(component_name)
+                if any(pattern in demangled for pattern in patterns):
+                    return f"{_COMPONENT_PREFIX_ESPHOME}{component_name}"
+
+        # Check for ESPHome component namespaces
+        match = ESPHOME_COMPONENT_PATTERN.search(demangled)
+        if match:
+            component_name = match.group(1)
+            # Strip trailing underscore if present (e.g., switch_ -> switch)
+            component_name = component_name.rstrip("_")
+
+            # Check if this is an actual component in the components directory
+            if component_name in get_esphome_components():
+                return f"{_COMPONENT_PREFIX_ESPHOME}{component_name}"
+            # Check if this is a known external component from the config
+            if component_name in self.external_components:
+                return f"{_COMPONENT_PREFIX_EXTERNAL}{component_name}"
+            # Everything else in esphome:: namespace is core
+            return _COMPONENT_CORE
+
+        # Check for esphome core namespace (no component namespace)
+        if _NAMESPACE_ESPHOME in demangled:
+            # If no component match found, it's core
+            return _COMPONENT_CORE
+
+        # Check against symbol patterns
+        for component, patterns in SYMBOL_PATTERNS.items():
+            if any(pattern in symbol_name for pattern in patterns):
+                return component
+
+        # Check against demangled patterns
+        for component, patterns in DEMANGLED_PATTERNS.items():
+            if any(pattern in demangled for pattern in patterns):
+                return component
+
+        # Special cases that need more complex logic
+
+        # Check if spi_flash vs spi_driver
+        if "spi_" in symbol_name or "SPI" in symbol_name:
+            return "spi_flash" if "spi_flash" in symbol_name else "spi_driver"
+
+        # libc special printf variants
+        if (
+            symbol_name.startswith("_")
+            and symbol_name[1:].replace("_r", "").replace("v", "").replace("s", "")
+            in _LIBC_PRINTF_SCANF_FAMILY
+        ):
+            return "libc"
+
+        # Track uncategorized symbols for analysis
+        return "other"
+
+    def _batch_demangle_symbols(self, symbols: list[str]) -> None:
+        """Batch demangle C++ symbol names for efficiency."""
+        if not symbols:
+            return
+
+        # Try to find the appropriate c++filt for the platform
+        cppfilt_cmd = "c++filt"
+
+        _LOGGER.info("Demangling %d symbols", len(symbols))
+        _LOGGER.debug("objdump_path = %s", self.objdump_path)
+
+        # Check if we have a toolchain-specific c++filt
+        if self.objdump_path and self.objdump_path != "objdump":
+            # Replace objdump with c++filt in the path
+            potential_cppfilt = self.objdump_path.replace("objdump", "c++filt")
+            _LOGGER.info("Checking for toolchain c++filt at: %s", potential_cppfilt)
+            if Path(potential_cppfilt).exists():
+                cppfilt_cmd = potential_cppfilt
+                _LOGGER.info("✓ Using toolchain c++filt: %s", cppfilt_cmd)
+            else:
+                _LOGGER.info(
+                    "✗ Toolchain c++filt not found at %s, using system c++filt",
+                    potential_cppfilt,
+                )
+        else:
+            _LOGGER.info("✗ Using system c++filt (objdump_path=%s)", self.objdump_path)
+
+        # Strip GCC optimization suffixes and prefixes before demangling
+        # Suffixes like $isra$0, $part$0, $constprop$0 confuse c++filt
+        # Prefixes like _GLOBAL__sub_I_ need to be removed and tracked
+        symbols_stripped: list[str] = []
+        symbols_prefixes: list[str] = []  # Track removed prefixes
+        for symbol in symbols:
+            # Remove GCC optimization markers
+            stripped = _GCC_OPTIMIZATION_SUFFIX_PATTERN.sub("", symbol)
+
+            # Handle GCC global constructor/initializer prefixes
+            # _GLOBAL__sub_I_<mangled> -> extract <mangled> for demangling
+            prefix = ""
+            for gcc_prefix in _GCC_PREFIX_ANNOTATIONS:
+                if stripped.startswith(gcc_prefix):
+                    prefix = gcc_prefix
+                    stripped = stripped[len(prefix) :]
+                    break
+
+            symbols_stripped.append(stripped)
+            symbols_prefixes.append(prefix)
+
+        try:
+            # Send all symbols to c++filt at once
+            result = subprocess.run(
+                [cppfilt_cmd],
+                input="\n".join(symbols_stripped),
+                capture_output=True,
+                text=True,
+                check=False,
+            )
+        except (subprocess.SubprocessError, OSError, UnicodeDecodeError) as e:
+            # On error, cache originals
+            _LOGGER.warning("Failed to batch demangle symbols: %s", e)
+            for symbol in symbols:
+                self._demangle_cache[symbol] = symbol
+            return
+
+        if result.returncode != 0:
+            _LOGGER.warning(
+                "c++filt exited with code %d: %s",
+                result.returncode,
+                result.stderr[:200] if result.stderr else "(no error output)",
+            )
+            # Cache originals on failure
+            for symbol in symbols:
+                self._demangle_cache[symbol] = symbol
+            return
+
+        # Process demangled output
+        self._process_demangled_output(
+            symbols, symbols_stripped, symbols_prefixes, result.stdout, cppfilt_cmd
+        )
+
+    def _process_demangled_output(
+        self,
+        symbols: list[str],
+        symbols_stripped: list[str],
+        symbols_prefixes: list[str],
+        demangled_output: str,
+        cppfilt_cmd: str,
+    ) -> None:
+        """Process demangled symbol output and populate cache.
+
+        Args:
+            symbols: Original symbol names
+            symbols_stripped: Stripped symbol names sent to c++filt
+            symbols_prefixes: Removed prefixes to restore
+            demangled_output: Output from c++filt
+            cppfilt_cmd: Path to c++filt command (for logging)
+        """
+        demangled_lines = demangled_output.strip().split("\n")
+        failed_count = 0
+
+        for original, stripped, prefix, demangled in zip(
+            symbols, symbols_stripped, symbols_prefixes, demangled_lines
+        ):
+            # Add back any prefix that was removed
+            demangled = self._restore_symbol_prefix(prefix, stripped, demangled)
+
+            # If we stripped a suffix, add it back to the demangled name for clarity
+            if original != stripped and not prefix:
+                demangled = self._restore_symbol_suffix(original, demangled)
+
+            self._demangle_cache[original] = demangled
+
+            # Log symbols that failed to demangle (stayed the same as stripped version)
+            if stripped == demangled and stripped.startswith("_Z"):
+                failed_count += 1
+                if failed_count <= 5:  # Only log first 5 failures
+                    _LOGGER.warning("Failed to demangle: %s", original)
+
+        if failed_count == 0:
+            _LOGGER.info("Successfully demangled all %d symbols", len(symbols))
+            return
+
+        _LOGGER.warning(
+            "Failed to demangle %d/%d symbols using %s",
+            failed_count,
+            len(symbols),
+            cppfilt_cmd,
+        )
+
+    @staticmethod
+    def _restore_symbol_prefix(prefix: str, stripped: str, demangled: str) -> str:
+        """Restore prefix that was removed before demangling.
+
+        Args:
+            prefix: Prefix that was removed (e.g., "_GLOBAL__sub_I_")
+            stripped: Stripped symbol name
+            demangled: Demangled symbol name
+
+        Returns:
+            Demangled name with prefix restored/annotated
+        """
+        if not prefix:
+            return demangled
+
+        # Successfully demangled - add descriptive prefix
+        if demangled != stripped and (
+            annotation := _GCC_PREFIX_ANNOTATIONS.get(prefix)
+        ):
+            return f"[{annotation}: {demangled}]"
+
+        # Failed to demangle - restore original prefix
+        return prefix + demangled
+
+    @staticmethod
+    def _restore_symbol_suffix(original: str, demangled: str) -> str:
+        """Restore GCC optimization suffix that was removed before demangling.
+
+        Args:
+            original: Original symbol name with suffix
+            demangled: Demangled symbol name without suffix
+
+        Returns:
+            Demangled name with suffix annotation
+        """
+        if suffix_match := _GCC_OPTIMIZATION_SUFFIX_PATTERN.search(original):
+            return f"{demangled} [{suffix_match.group(1)}]"
+        return demangled
+
+    def _demangle_symbol(self, symbol: str) -> str:
+        """Get demangled C++ symbol name from cache."""
+        return self._demangle_cache.get(symbol, symbol)
+
+    def _categorize_esphome_core_symbol(self, demangled: str) -> str:
+        """Categorize ESPHome core symbols into subcategories."""
+        # Special patterns that need to be checked separately
+        if any(pattern in demangled for pattern in _CPP_RUNTIME_PATTERNS):
+            return "C++ Runtime (vtables/RTTI)"
+
+        if demangled.startswith(_NAMESPACE_STD):
+            return "C++ STL"
+
+        # Check against patterns from const.py
+        for category, patterns in CORE_SUBCATEGORY_PATTERNS.items():
+            if any(pattern in demangled for pattern in patterns):
+                return category
+
+        return "Other Core"
+
+
+if __name__ == "__main__":
+    from .cli import main
+
+    main()

esphome/analyze_memory/__main__.py

@@ -0,0 +1,6 @@
+"""Main entry point for running the memory analyzer as a module."""
+
+from .cli import main
+
+if __name__ == "__main__":
+    main()

esphome/analyze_memory/cli.py

@@ -0,0 +1,421 @@
+"""CLI interface for memory analysis with report generation."""
+
+from collections import defaultdict
+import sys
+
+from . import (
+    _COMPONENT_API,
+    _COMPONENT_CORE,
+    _COMPONENT_PREFIX_ESPHOME,
+    _COMPONENT_PREFIX_EXTERNAL,
+    MemoryAnalyzer,
+)
+
+
+class MemoryAnalyzerCLI(MemoryAnalyzer):
+    """Memory analyzer with CLI-specific report generation."""
+
+    # Column width constants
+    COL_COMPONENT: int = 29
+    COL_FLASH_TEXT: int = 14
+    COL_FLASH_DATA: int = 14
+    COL_RAM_DATA: int = 12
+    COL_RAM_BSS: int = 12
+    COL_TOTAL_FLASH: int = 15
+    COL_TOTAL_RAM: int = 12
+    COL_SEPARATOR: int = 3  # " | "
+
+    # Core analysis column widths
+    COL_CORE_SUBCATEGORY: int = 30
+    COL_CORE_SIZE: int = 12
+    COL_CORE_COUNT: int = 6
+    COL_CORE_PERCENT: int = 10
+
+    # Calculate table width once at class level
+    TABLE_WIDTH: int = (
+        COL_COMPONENT
+        + COL_SEPARATOR
+        + COL_FLASH_TEXT
+        + COL_SEPARATOR
+        + COL_FLASH_DATA
+        + COL_SEPARATOR
+        + COL_RAM_DATA
+        + COL_SEPARATOR
+        + COL_RAM_BSS
+        + COL_SEPARATOR
+        + COL_TOTAL_FLASH
+        + COL_SEPARATOR
+        + COL_TOTAL_RAM
+    )
+
+    @staticmethod
+    def _make_separator_line(*widths: int) -> str:
+        """Create a separator line with given column widths.
+
+        Args:
+            widths: Column widths to create separators for
+
+        Returns:
+            Separator line like "----+---------+-----"
+        """
+        return "-+-".join("-" * width for width in widths)
+
+    # Pre-computed separator lines
+    MAIN_TABLE_SEPARATOR: str = _make_separator_line(
+        COL_COMPONENT,
+        COL_FLASH_TEXT,
+        COL_FLASH_DATA,
+        COL_RAM_DATA,
+        COL_RAM_BSS,
+        COL_TOTAL_FLASH,
+        COL_TOTAL_RAM,
+    )
+
+    CORE_TABLE_SEPARATOR: str = _make_separator_line(
+        COL_CORE_SUBCATEGORY,
+        COL_CORE_SIZE,
+        COL_CORE_COUNT,
+        COL_CORE_PERCENT,
+    )
+
+    def generate_report(self, detailed: bool = False) -> str:
+        """Generate a formatted memory report."""
+        components = sorted(
+            self.components.items(), key=lambda x: x[1].flash_total, reverse=True
+        )
+
+        # Calculate totals
+        total_flash = sum(c.flash_total for _, c in components)
+        total_ram = sum(c.ram_total for _, c in components)
+
+        # Build report
+        lines: list[str] = []
+
+        lines.append("=" * self.TABLE_WIDTH)
+        lines.append("Component Memory Analysis".center(self.TABLE_WIDTH))
+        lines.append("=" * self.TABLE_WIDTH)
+        lines.append("")
+
+        # Main table - fixed column widths
+        lines.append(
+            f"{'Component':<{self.COL_COMPONENT}} | {'Flash (text)':>{self.COL_FLASH_TEXT}} | {'Flash (data)':>{self.COL_FLASH_DATA}} | {'RAM (data)':>{self.COL_RAM_DATA}} | {'RAM (bss)':>{self.COL_RAM_BSS}} | {'Total Flash':>{self.COL_TOTAL_FLASH}} | {'Total RAM':>{self.COL_TOTAL_RAM}}"
+        )
+        lines.append(self.MAIN_TABLE_SEPARATOR)
+
+        for name, mem in components:
+            if mem.flash_total > 0 or mem.ram_total > 0:
+                flash_rodata = mem.rodata_size + mem.data_size
+                lines.append(
+                    f"{name:<{self.COL_COMPONENT}} | {mem.text_size:>{self.COL_FLASH_TEXT - 2},} B | {flash_rodata:>{self.COL_FLASH_DATA - 2},} B | "
+                    f"{mem.data_size:>{self.COL_RAM_DATA - 2},} B | {mem.bss_size:>{self.COL_RAM_BSS - 2},} B | "
+                    f"{mem.flash_total:>{self.COL_TOTAL_FLASH - 2},} B | {mem.ram_total:>{self.COL_TOTAL_RAM - 2},} B"
+                )
+
+        lines.append(self.MAIN_TABLE_SEPARATOR)
+        lines.append(
+            f"{'TOTAL':<{self.COL_COMPONENT}} | {' ':>{self.COL_FLASH_TEXT}} | {' ':>{self.COL_FLASH_DATA}} | "
+            f"{' ':>{self.COL_RAM_DATA}} | {' ':>{self.COL_RAM_BSS}} | "
+            f"{total_flash:>{self.COL_TOTAL_FLASH - 2},} B | {total_ram:>{self.COL_TOTAL_RAM - 2},} B"
+        )
+
+        # Top consumers
+        lines.append("")
+        lines.append("Top Flash Consumers:")
+        for i, (name, mem) in enumerate(components[:25]):
+            if mem.flash_total > 0:
+                percentage = (
+                    (mem.flash_total / total_flash * 100) if total_flash > 0 else 0
+                )
+                lines.append(
+                    f"{i + 1}. {name} ({mem.flash_total:,} B) - {percentage:.1f}% of analyzed flash"
+                )
+
+        lines.append("")
+        lines.append("Top RAM Consumers:")
+        ram_components = sorted(components, key=lambda x: x[1].ram_total, reverse=True)
+        for i, (name, mem) in enumerate(ram_components[:25]):
+            if mem.ram_total > 0:
+                percentage = (mem.ram_total / total_ram * 100) if total_ram > 0 else 0
+                lines.append(
+                    f"{i + 1}. {name} ({mem.ram_total:,} B) - {percentage:.1f}% of analyzed RAM"
+                )
+
+        lines.append("")
+        lines.append(
+            "Note: This analysis covers symbols in the ELF file. Some runtime allocations may not be included."
+        )
+        lines.append("=" * self.TABLE_WIDTH)
+
+        # Add ESPHome core detailed analysis if there are core symbols
+        if self._esphome_core_symbols:
+            lines.append("")
+            lines.append("=" * self.TABLE_WIDTH)
+            lines.append(
+                f"{_COMPONENT_CORE} Detailed Analysis".center(self.TABLE_WIDTH)
+            )
+            lines.append("=" * self.TABLE_WIDTH)
+            lines.append("")
+
+            # Group core symbols by subcategory
+            core_subcategories: dict[str, list[tuple[str, str, int]]] = defaultdict(
+                list
+            )
+
+            for symbol, demangled, size in self._esphome_core_symbols:
+                # Categorize based on demangled name patterns
+                subcategory = self._categorize_esphome_core_symbol(demangled)
+                core_subcategories[subcategory].append((symbol, demangled, size))
+
+            # Sort subcategories by total size
+            sorted_subcategories = sorted(
+                [
+                    (name, symbols, sum(s[2] for s in symbols))
+                    for name, symbols in core_subcategories.items()
+                ],
+                key=lambda x: x[2],
+                reverse=True,
+            )
+
+            lines.append(
+                f"{'Subcategory':<{self.COL_CORE_SUBCATEGORY}} | {'Size':>{self.COL_CORE_SIZE}} | "
+                f"{'Count':>{self.COL_CORE_COUNT}} | {'% of Core':>{self.COL_CORE_PERCENT}}"
+            )
+            lines.append(self.CORE_TABLE_SEPARATOR)
+
+            core_total = sum(size for _, _, size in self._esphome_core_symbols)
+
+            for subcategory, symbols, total_size in sorted_subcategories:
+                percentage = (total_size / core_total * 100) if core_total > 0 else 0
+                lines.append(
+                    f"{subcategory:<{self.COL_CORE_SUBCATEGORY}} | {total_size:>{self.COL_CORE_SIZE - 2},} B | "
+                    f"{len(symbols):>{self.COL_CORE_COUNT}} | {percentage:>{self.COL_CORE_PERCENT - 1}.1f}%"
+                )
+
+            # Top 15 largest core symbols
+            lines.append("")
+            lines.append(f"Top 15 Largest {_COMPONENT_CORE} Symbols:")
+            sorted_core_symbols = sorted(
+                self._esphome_core_symbols, key=lambda x: x[2], reverse=True
+            )
+
+            for i, (symbol, demangled, size) in enumerate(sorted_core_symbols[:15]):
+                lines.append(f"{i + 1}. {demangled} ({size:,} B)")
+
+            lines.append("=" * self.TABLE_WIDTH)
+
+        # Add detailed analysis for top ESPHome and external components
+        esphome_components = [
+            (name, mem)
+            for name, mem in components
+            if name.startswith(_COMPONENT_PREFIX_ESPHOME) and name != _COMPONENT_CORE
+        ]
+        external_components = [
+            (name, mem)
+            for name, mem in components
+            if name.startswith(_COMPONENT_PREFIX_EXTERNAL)
+        ]
+
+        top_esphome_components = sorted(
+            esphome_components, key=lambda x: x[1].flash_total, reverse=True
+        )[:30]
+
+        # Include all external components (they're usually important)
+        top_external_components = sorted(
+            external_components, key=lambda x: x[1].flash_total, reverse=True
+        )
+
+        # Check if API component exists and ensure it's included
+        api_component = None
+        for name, mem in components:
+            if name == _COMPONENT_API:
+                api_component = (name, mem)
+                break
+
+        # Also include wifi_stack and other important system components if they exist
+        system_components_to_include = [
+            # Empty list - we've finished debugging symbol categorization
+            # Add component names here if you need to debug their symbols
+        ]
+        system_components = [
+            (name, mem)
+            for name, mem in components
+            if name in system_components_to_include
+        ]
+
+        # Combine all components to analyze: top ESPHome + all external + API if not already included + system components
+        components_to_analyze = (
+            list(top_esphome_components)
+            + list(top_external_components)
+            + system_components
+        )
+        if api_component and api_component not in components_to_analyze:
+            components_to_analyze.append(api_component)
+
+        if components_to_analyze:
+            for comp_name, comp_mem in components_to_analyze:
+                if not (comp_symbols := self._component_symbols.get(comp_name, [])):
+                    continue
+                lines.append("")
+                lines.append("=" * self.TABLE_WIDTH)
+                lines.append(f"{comp_name} Detailed Analysis".center(self.TABLE_WIDTH))
+                lines.append("=" * self.TABLE_WIDTH)
+                lines.append("")
+
+                # Sort symbols by size
+                sorted_symbols = sorted(comp_symbols, key=lambda x: x[2], reverse=True)
+
+                lines.append(f"Total symbols: {len(sorted_symbols)}")
+                lines.append(f"Total size: {comp_mem.flash_total:,} B")
+                lines.append("")
+
+                # Show all symbols > 100 bytes for better visibility
+                large_symbols = [
+                    (sym, dem, size) for sym, dem, size in sorted_symbols if size > 100
+                ]
+
+                lines.append(
+                    f"{comp_name} Symbols > 100 B ({len(large_symbols)} symbols):"
+                )
+                for i, (symbol, demangled, size) in enumerate(large_symbols):
+                    lines.append(f"{i + 1}. {demangled} ({size:,} B)")
+
+                lines.append("=" * self.TABLE_WIDTH)
+
+        return "\n".join(lines)
+
+    def dump_uncategorized_symbols(self, output_file: str | None = None) -> None:
+        """Dump uncategorized symbols for analysis."""
+        # Sort by size descending
+        sorted_symbols = sorted(
+            self._uncategorized_symbols, key=lambda x: x[2], reverse=True
+        )
+
+        lines = ["Uncategorized Symbols Analysis", "=" * 80]
+        lines.append(f"Total uncategorized symbols: {len(sorted_symbols)}")
+        lines.append(
+            f"Total uncategorized size: {sum(s[2] for s in sorted_symbols):,} bytes"
+        )
+        lines.append("")
+        lines.append(f"{'Size':>10} | {'Symbol':<60} | Demangled")
+        lines.append("-" * 10 + "-+-" + "-" * 60 + "-+-" + "-" * 40)
+
+        for symbol, demangled, size in sorted_symbols[:100]:  # Top 100
+            demangled_display = (
+                demangled[:100] if symbol != demangled else "[not demangled]"
+            )
+            lines.append(f"{size:>10,} | {symbol[:60]:<60} | {demangled_display}")
+
+        if len(sorted_symbols) > 100:
+            lines.append(f"\n... and {len(sorted_symbols) - 100} more symbols")
+
+        content = "\n".join(lines)
+
+        if output_file:
+            with open(output_file, "w", encoding="utf-8") as f:
+                f.write(content)
+        else:
+            print(content)
+
+
+def analyze_elf(
+    elf_path: str,
+    objdump_path: str | None = None,
+    readelf_path: str | None = None,
+    detailed: bool = False,
+    external_components: set[str] | None = None,
+) -> str:
+    """Analyze an ELF file and return a memory report."""
+    analyzer = MemoryAnalyzerCLI(
+        elf_path, objdump_path, readelf_path, external_components
+    )
+    analyzer.analyze()
+    return analyzer.generate_report(detailed)
+
+
+def main():
+    """CLI entrypoint for memory analysis."""
+    if len(sys.argv) < 2:
+        print("Usage: python -m esphome.analyze_memory <build_directory>")
+        print("\nAnalyze memory usage from an ESPHome build directory.")
+        print("The build directory should contain firmware.elf and idedata will be")
+        print("loaded from ~/.esphome/.internal/idedata/<device>.json")
+        print("\nExamples:")
+        print("  python -m esphome.analyze_memory ~/.esphome/build/my-device")
+        print("  python -m esphome.analyze_memory .esphome/build/my-device")
+        print("  python -m esphome.analyze_memory my-device  # Short form")
+        sys.exit(1)
+
+    build_dir = sys.argv[1]
+
+    # Load build directory
+    import json
+    from pathlib import Path
+
+    from esphome.platformio_api import IDEData
+
+    build_path = Path(build_dir)
+
+    # If no path separator in name, assume it's a device name
+    if "/" not in build_dir and not build_path.is_dir():
+        # Try current directory first
+        cwd_path = Path.cwd() / ".esphome" / "build" / build_dir
+        if cwd_path.is_dir():
+            build_path = cwd_path
+            print(f"Using build directory: {build_path}", file=sys.stderr)
+        else:
+            # Fall back to home directory
+            build_path = Path.home() / ".esphome" / "build" / build_dir
+            print(f"Using build directory: {build_path}", file=sys.stderr)
+
+    if not build_path.is_dir():
+        print(f"Error: {build_path} is not a directory", file=sys.stderr)
+        sys.exit(1)
+
+    # Find firmware.elf
+    elf_file = None
+    for elf_candidate in [
+        build_path / "firmware.elf",
+        build_path / ".pioenvs" / build_path.name / "firmware.elf",
+    ]:
+        if elf_candidate.exists():
+            elf_file = str(elf_candidate)
+            break
+
+    if not elf_file:
+        print(f"Error: firmware.elf not found in {build_dir}", file=sys.stderr)
+        sys.exit(1)
+
+    # Find idedata.json - check current directory first, then home
+    device_name = build_path.name
+    idedata_candidates = [
+        Path.cwd() / ".esphome" / "idedata" / f"{device_name}.json",
+        Path.home() / ".esphome" / "idedata" / f"{device_name}.json",
+    ]
+
+    idedata = None
+    for idedata_path in idedata_candidates:
+        if not idedata_path.exists():
+            continue
+        try:
+            with open(idedata_path, encoding="utf-8") as f:
+                raw_data = json.load(f)
+            idedata = IDEData(raw_data)
+            print(f"Loaded idedata from: {idedata_path}", file=sys.stderr)
+            break
+        except (json.JSONDecodeError, OSError) as e:
+            print(f"Warning: Failed to load idedata: {e}", file=sys.stderr)
+
+    if not idedata:
+        print(
+            f"Warning: idedata not found (searched {idedata_candidates[0]} and {idedata_candidates[1]})",
+            file=sys.stderr,
+        )
+
+    analyzer = MemoryAnalyzerCLI(elf_file, idedata=idedata)
+    analyzer.analyze()
+    report = analyzer.generate_report()
+    print(report)
+
+
+if __name__ == "__main__":
+    main()

esphome/analyze_memory/helpers.py

@@ -0,0 +1,121 @@
+"""Helper functions for memory analysis."""
+
+from functools import cache
+from pathlib import Path
+
+from .const import SECTION_MAPPING
+
+# Import namespace constant from parent module
+# Note: This would create a circular import if done at module level,
+# so we'll define it locally here as well
+_NAMESPACE_ESPHOME = "esphome::"
+
+
+# Get the list of actual ESPHome components by scanning the components directory
+@cache
+def get_esphome_components():
+    """Get set of actual ESPHome components from the components directory."""
+    # Find the components directory relative to this file
+    # Go up two levels from analyze_memory/helpers.py to esphome/
+    current_dir = Path(__file__).parent.parent
+    components_dir = current_dir / "components"
+
+    if not components_dir.exists() or not components_dir.is_dir():
+        return frozenset()
+
+    return frozenset(
+        item.name
+        for item in components_dir.iterdir()
+        if item.is_dir()
+        and not item.name.startswith(".")
+        and not item.name.startswith("__")
+    )
+
+
+@cache
+def get_component_class_patterns(component_name: str) -> list[str]:
+    """Generate component class name patterns for symbol matching.
+
+    Args:
+        component_name: The component name (e.g., "ota", "wifi", "api")
+
+    Returns:
+        List of pattern strings to match against demangled symbols
+    """
+    component_upper = component_name.upper()
+    component_camel = component_name.replace("_", "").title()
+    return [
+        f"{_NAMESPACE_ESPHOME}{component_upper}Component",  # e.g., esphome::OTAComponent
+        f"{_NAMESPACE_ESPHOME}ESPHome{component_upper}Component",  # e.g., esphome::ESPHomeOTAComponent
+        f"{_NAMESPACE_ESPHOME}{component_camel}Component",  # e.g., esphome::OtaComponent
+        f"{_NAMESPACE_ESPHOME}ESPHome{component_camel}Component",  # e.g., esphome::ESPHomeOtaComponent
+    ]
+
+
+def map_section_name(raw_section: str) -> str | None:
+    """Map raw section name to standard section.
+
+    Args:
+        raw_section: Raw section name from ELF file (e.g., ".iram0.text", ".rodata.str1.1")
+
+    Returns:
+        Standard section name (".text", ".rodata", ".data", ".bss") or None
+    """
+    for standard_section, patterns in SECTION_MAPPING.items():
+        if any(pattern in raw_section for pattern in patterns):
+            return standard_section
+    return None
+
+
+def parse_symbol_line(line: str) -> tuple[str, str, int, str] | None:
+    """Parse a single symbol line from objdump output.
+
+    Args:
+        line: Line from objdump -t output
+
+    Returns:
+        Tuple of (section, name, size, address) or None if not a valid symbol.
+        Format: address l/g w/d F/O section size name
+        Example: 40084870 l     F .iram0.text    00000000 _xt_user_exc
+    """
+    parts = line.split()
+    if len(parts) < 5:
+        return None
+
+    try:
+        # Validate and extract address
+        address = parts[0]
+        int(address, 16)
+    except ValueError:
+        return None
+
+    # Look for F (function) or O (object) flag
+    if "F" not in parts and "O" not in parts:
+        return None
+
+    # Find section, size, and name
+    for i, part in enumerate(parts):
+        if not part.startswith("."):
+            continue
+
+        section = map_section_name(part)
+        if not section:
+            break
+
+        # Need at least size field after section
+        if i + 1 >= len(parts):
+            break
+
+        try:
+            size = int(parts[i + 1], 16)
+        except ValueError:
+            break
+
+        # Need symbol name and non-zero size
+        if i + 2 >= len(parts) or size == 0:
+            break
+
+        name = " ".join(parts[i + 2 :])
+        return (section, name, size, address)
+
+    return None

esphome/automation.py

@@ -15,8 +15,13 @@ from esphome.const import (
     CONF_TYPE_ID,
     CONF_UPDATE_INTERVAL,
 )
-from esphome.core import ID
-from esphome.cpp_generator import MockObj, MockObjClass, TemplateArgsType
+from esphome.core import ID, Lambda
+from esphome.cpp_generator import (
+    LambdaExpression,
+    MockObj,
+    MockObjClass,
+    TemplateArgsType,
+)
 from esphome.schema_extractors import SCHEMA_EXTRACT, schema_extractor
 from esphome.types import ConfigType
 from esphome.util import Registry
@@ -87,6 +92,7 @@ def validate_potentially_or_condition(value):
 
 DelayAction = cg.esphome_ns.class_("DelayAction", Action, cg.Component)
 LambdaAction = cg.esphome_ns.class_("LambdaAction", Action)
+StatelessLambdaAction = cg.esphome_ns.class_("StatelessLambdaAction", Action)
 IfAction = cg.esphome_ns.class_("IfAction", Action)
 WhileAction = cg.esphome_ns.class_("WhileAction", Action)
 RepeatAction = cg.esphome_ns.class_("RepeatAction", Action)
@@ -97,9 +103,40 @@ ResumeComponentAction = cg.esphome_ns.class_("ResumeComponentAction", Action)
 Automation = cg.esphome_ns.class_("Automation")
 
 LambdaCondition = cg.esphome_ns.class_("LambdaCondition", Condition)
+StatelessLambdaCondition = cg.esphome_ns.class_("StatelessLambdaCondition", Condition)
 ForCondition = cg.esphome_ns.class_("ForCondition", Condition, cg.Component)
 
 
+def new_lambda_pvariable(
+    id_obj: ID,
+    lambda_expr: LambdaExpression,
+    stateless_class: MockObjClass,
+    template_arg: cg.TemplateArguments | None = None,
+) -> MockObj:
+    """Create Pvariable for lambda, using stateless class if applicable.
+
+    Combines ID selection and Pvariable creation in one call. For stateless
+    lambdas (empty capture), uses function pointer instead of std::function.
+
+    Args:
+        id_obj: The ID object (action_id, condition_id, or filter_id)
+        lambda_expr: The lambda expression object
+        stateless_class: The stateless class to use for stateless lambdas
+        template_arg: Optional template arguments (for actions/conditions)
+
+    Returns:
+        The created Pvariable
+    """
+    # For stateless lambdas, use function pointer instead of std::function
+    if lambda_expr.capture == "":
+        id_obj = id_obj.copy()
+        id_obj.type = stateless_class
+
+    if template_arg is not None:
+        return cg.new_Pvariable(id_obj, template_arg, lambda_expr)
+    return cg.new_Pvariable(id_obj, lambda_expr)
+
+
 def validate_automation(extra_schema=None, extra_validators=None, single=False):
     if extra_schema is None:
         extra_schema = {}
@@ -145,7 +182,7 @@ def validate_automation(extra_schema=None, extra_validators=None, single=False):
             value = cv.Schema([extra_validators])(value)
         if single:
             if len(value) != 1:
-                raise cv.Invalid("Cannot have more than 1 automation for templates")
+                raise cv.Invalid("This trigger allows only a single automation")
             return value[0]
         return value
 
@@ -240,7 +277,9 @@ async def lambda_condition_to_code(
     args: TemplateArgsType,
 ) -> MockObj:
     lambda_ = await cg.process_lambda(config, args, return_type=bool)
-    return cg.new_Pvariable(condition_id, template_arg, lambda_)
+    return new_lambda_pvariable(
+        condition_id, lambda_, StatelessLambdaCondition, template_arg
+    )
 
 
 @register_condition(
@@ -271,6 +310,30 @@ async def for_condition_to_code(
     return var
 
 
+@register_condition(
+    "component.is_idle",
+    LambdaCondition,
+    maybe_simple_id(
+        {
+            cv.Required(CONF_ID): cv.use_id(cg.Component),
+        }
+    ),
+)
+async def component_is_idle_condition_to_code(
+    config: ConfigType,
+    condition_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+) -> MockObj:
+    comp = await cg.get_variable(config[CONF_ID])
+    lambda_ = await cg.process_lambda(
+        Lambda(f"return {comp}->is_idle();"), args, return_type=bool
+    )
+    return new_lambda_pvariable(
+        condition_id, lambda_, StatelessLambdaCondition, template_arg
+    )
+
+
 @register_action(
     "delay", DelayAction, cv.templatable(cv.positive_time_period_milliseconds)
 )
@@ -406,7 +469,7 @@ async def lambda_action_to_code(
     args: TemplateArgsType,
 ) -> MockObj:
     lambda_ = await cg.process_lambda(config, args, return_type=cg.void)
-    return cg.new_Pvariable(action_id, template_arg, lambda_)
+    return new_lambda_pvariable(action_id, lambda_, StatelessLambdaAction, template_arg)
 
 
 @register_action(

esphome/codegen.py

@@ -62,6 +62,7 @@ from esphome.cpp_types import (  # noqa: F401
     EntityBase,
     EntityCategory,
     ESPTime,
+    FixedVector,
     GPIOPin,
     InternalGPIOPin,
     JsonObject,

esphome/components/adalight/adalight_light_effect.cpp

@@ -9,7 +9,7 @@ static const char *const TAG = "adalight_light_effect";
 static const uint32_t ADALIGHT_ACK_INTERVAL = 1000;
 static const uint32_t ADALIGHT_RECEIVE_TIMEOUT = 1000;
 
-AdalightLightEffect::AdalightLightEffect(const std::string &name) : AddressableLightEffect(name) {}
+AdalightLightEffect::AdalightLightEffect(const char *name) : AddressableLightEffect(name) {}
 
 void AdalightLightEffect::start() {
   AddressableLightEffect::start();

esphome/components/adalight/adalight_light_effect.h

@@ -11,7 +11,7 @@ namespace adalight {
 
 class AdalightLightEffect : public light::AddressableLightEffect, public uart::UARTDevice {
  public:
-  AdalightLightEffect(const std::string &name);
+  AdalightLightEffect(const char *name);
 
   void start() override;
   void stop() override;

esphome/components/ags10/ags10.h

@@ -105,7 +105,7 @@ template<typename... Ts> class AGS10NewI2cAddressAction : public Action<Ts...>,
  public:
   TEMPLATABLE_VALUE(uint8_t, new_address)
 
-  void play(Ts... x) override { this->parent_->new_i2c_address(this->new_address_.value(x...)); }
+  void play(const Ts &...x) override { this->parent_->new_i2c_address(this->new_address_.value(x...)); }
 };
 
 enum AGS10SetZeroPointActionMode {
@@ -122,7 +122,7 @@ template<typename... Ts> class AGS10SetZeroPointAction : public Action<Ts...>, p
   TEMPLATABLE_VALUE(uint16_t, value)
   TEMPLATABLE_VALUE(AGS10SetZeroPointActionMode, mode)
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     switch (this->mode_.value(x...)) {
       case FACTORY_DEFAULT:
         this->parent_->set_zero_point_with_factory_defaults();

esphome/components/aic3204/automation.h

@@ -13,7 +13,7 @@ template<typename... Ts> class SetAutoMuteAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(uint8_t, auto_mute_mode)
 
-  void play(Ts... x) override { this->aic3204_->set_auto_mute_mode(this->auto_mute_mode_.value(x...)); }
+  void play(const Ts &...x) override { this->aic3204_->set_auto_mute_mode(this->auto_mute_mode_.value(x...)); }
 
  protected:
   AIC3204 *aic3204_;

esphome/components/alarm_control_panel/__init__.py

@@ -172,12 +172,6 @@ def alarm_control_panel_schema(
     return _ALARM_CONTROL_PANEL_SCHEMA.extend(schema)
 
 
-# Remove before 2025.11.0
-ALARM_CONTROL_PANEL_SCHEMA = alarm_control_panel_schema(AlarmControlPanel)
-ALARM_CONTROL_PANEL_SCHEMA.add_extra(
-    cv.deprecated_schema_constant("alarm_control_panel")
-)
-
 ALARM_CONTROL_PANEL_ACTION_SCHEMA = maybe_simple_id(
     {
         cv.GenerateID(): cv.use_id(AlarmControlPanel),

esphome/components/alarm_control_panel/alarm_control_panel.cpp

@@ -1,6 +1,8 @@
-#include <utility>
-
 #include "alarm_control_panel.h"
+#include "esphome/core/defines.h"
+#include "esphome/core/controller_registry.h"
+
+#include <utility>
 
 #include "esphome/core/application.h"
 #include "esphome/core/helpers.h"
@@ -34,6 +36,9 @@ void AlarmControlPanel::publish_state(AlarmControlPanelState state) {
              LOG_STR_ARG(alarm_control_panel_state_to_string(prev_state)));
     this->current_state_ = state;
     this->state_callback_.call();
+#if defined(USE_ALARM_CONTROL_PANEL) && defined(USE_CONTROLLER_REGISTRY)
+    ControllerRegistry::notify_alarm_control_panel_update(this);
+#endif
     if (state == ACP_STATE_TRIGGERED) {
       this->triggered_callback_.call();
     } else if (state == ACP_STATE_ARMING) {

esphome/components/alarm_control_panel/automation.h

@@ -89,7 +89,7 @@ template<typename... Ts> class ArmAwayAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(std::string, code)
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     auto call = this->alarm_control_panel_->make_call();
     auto code = this->code_.optional_value(x...);
     if (code.has_value()) {
@@ -109,7 +109,7 @@ template<typename... Ts> class ArmHomeAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(std::string, code)
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     auto call = this->alarm_control_panel_->make_call();
     auto code = this->code_.optional_value(x...);
     if (code.has_value()) {
@@ -129,7 +129,7 @@ template<typename... Ts> class ArmNightAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(std::string, code)
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     auto call = this->alarm_control_panel_->make_call();
     auto code = this->code_.optional_value(x...);
     if (code.has_value()) {
@@ -149,7 +149,7 @@ template<typename... Ts> class DisarmAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(std::string, code)
 
-  void play(Ts... x) override { this->alarm_control_panel_->disarm(this->code_.optional_value(x...)); }
+  void play(const Ts &...x) override { this->alarm_control_panel_->disarm(this->code_.optional_value(x...)); }
 
  protected:
   AlarmControlPanel *alarm_control_panel_;
@@ -159,7 +159,7 @@ template<typename... Ts> class PendingAction : public Action<Ts...> {
  public:
   explicit PendingAction(AlarmControlPanel *alarm_control_panel) : alarm_control_panel_(alarm_control_panel) {}
 
-  void play(Ts... x) override { this->alarm_control_panel_->make_call().pending().perform(); }
+  void play(const Ts &...x) override { this->alarm_control_panel_->make_call().pending().perform(); }
 
  protected:
   AlarmControlPanel *alarm_control_panel_;
@@ -169,7 +169,7 @@ template<typename... Ts> class TriggeredAction : public Action<Ts...> {
  public:
   explicit TriggeredAction(AlarmControlPanel *alarm_control_panel) : alarm_control_panel_(alarm_control_panel) {}
 
-  void play(Ts... x) override { this->alarm_control_panel_->make_call().triggered().perform(); }
+  void play(const Ts &...x) override { this->alarm_control_panel_->make_call().triggered().perform(); }
 
  protected:
   AlarmControlPanel *alarm_control_panel_;
@@ -178,7 +178,7 @@ template<typename... Ts> class TriggeredAction : public Action<Ts...> {
 template<typename... Ts> class AlarmControlPanelCondition : public Condition<Ts...> {
  public:
   AlarmControlPanelCondition(AlarmControlPanel *parent) : parent_(parent) {}
-  bool check(Ts... x) override {
+  bool check(const Ts &...x) override {
     return this->parent_->is_state_armed(this->parent_->get_state()) ||
            this->parent_->get_state() == ACP_STATE_PENDING || this->parent_->get_state() == ACP_STATE_TRIGGERED;
   }

esphome/components/animation/animation.cpp

@@ -26,12 +26,12 @@ uint32_t Animation::get_animation_frame_count() const { return this->animation_f
 int Animation::get_current_frame() const { return this->current_frame_; }
 void Animation::next_frame() {
   this->current_frame_++;
-  if (loop_count_ && this->current_frame_ == loop_end_frame_ &&
+  if (loop_count_ && static_cast<uint32_t>(this->current_frame_) == loop_end_frame_ &&
       (this->loop_current_iteration_ < loop_count_ || loop_count_ < 0)) {
     this->current_frame_ = loop_start_frame_;
     this->loop_current_iteration_++;
   }
-  if (this->current_frame_ >= animation_frame_count_) {
+  if (static_cast<uint32_t>(this->current_frame_) >= animation_frame_count_) {
     this->loop_current_iteration_ = 1;
     this->current_frame_ = 0;
   }

esphome/components/animation/animation.h

@@ -39,7 +39,7 @@ class Animation : public image::Image {
 template<typename... Ts> class AnimationNextFrameAction : public Action<Ts...> {
  public:
   AnimationNextFrameAction(Animation *parent) : parent_(parent) {}
-  void play(Ts... x) override { this->parent_->next_frame(); }
+  void play(const Ts &...x) override { this->parent_->next_frame(); }
 
  protected:
   Animation *parent_;
@@ -48,7 +48,7 @@ template<typename... Ts> class AnimationNextFrameAction : public Action<Ts...> {
 template<typename... Ts> class AnimationPrevFrameAction : public Action<Ts...> {
  public:
   AnimationPrevFrameAction(Animation *parent) : parent_(parent) {}
-  void play(Ts... x) override { this->parent_->prev_frame(); }
+  void play(const Ts &...x) override { this->parent_->prev_frame(); }
 
  protected:
   Animation *parent_;
@@ -58,7 +58,7 @@ template<typename... Ts> class AnimationSetFrameAction : public Action<Ts...> {
  public:
   AnimationSetFrameAction(Animation *parent) : parent_(parent) {}
   TEMPLATABLE_VALUE(uint16_t, frame)
-  void play(Ts... x) override { this->parent_->set_frame(this->frame_.value(x...)); }
+  void play(const Ts &...x) override { this->parent_->set_frame(this->frame_.value(x...)); }
 
  protected:
   Animation *parent_;

esphome/components/anova/anova.h

@@ -28,7 +28,7 @@ class Anova : public climate::Climate, public esphome::ble_client::BLEClientNode
   void dump_config() override;
   climate::ClimateTraits traits() override {
     auto traits = climate::ClimateTraits();
-    traits.set_supports_current_temperature(true);
+    traits.add_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_TEMPERATURE);
     traits.set_supported_modes({climate::CLIMATE_MODE_OFF, climate::ClimateMode::CLIMATE_MODE_HEAT});
     traits.set_visual_min_temperature(25.0);
     traits.set_visual_max_temperature(100.0);

esphome/components/api/__init__.py

@@ -9,6 +9,7 @@ import esphome.config_validation as cv
 from esphome.const import (
     CONF_ACTION,
     CONF_ACTIONS,
+    CONF_CAPTURE_RESPONSE,
     CONF_DATA,
     CONF_DATA_TEMPLATE,
     CONF_EVENT,
@@ -17,30 +18,50 @@ from esphome.const import (
     CONF_MAX_CONNECTIONS,
     CONF_ON_CLIENT_CONNECTED,
     CONF_ON_CLIENT_DISCONNECTED,
+    CONF_ON_ERROR,
+    CONF_ON_SUCCESS,
     CONF_PASSWORD,
     CONF_PORT,
     CONF_REBOOT_TIMEOUT,
+    CONF_RESPONSE_TEMPLATE,
     CONF_SERVICE,
     CONF_SERVICES,
     CONF_TAG,
     CONF_TRIGGER_ID,
     CONF_VARIABLES,
 )
-from esphome.core import CORE, CoroPriority, coroutine_with_priority
+from esphome.core import CORE, ID, CoroPriority, coroutine_with_priority
+from esphome.cpp_generator import TemplateArgsType
 from esphome.types import ConfigType
 
 _LOGGER = logging.getLogger(__name__)
 
 DOMAIN = "api"
 DEPENDENCIES = ["network"]
-AUTO_LOAD = ["socket"]
 CODEOWNERS = ["@esphome/core"]
 
+
+def AUTO_LOAD(config: ConfigType) -> list[str]:
+    """Conditionally auto-load json only when capture_response is used."""
+    base = ["socket"]
+
+    # Check if any homeassistant.action/homeassistant.service has capture_response: true
+    # This flag is set during config validation in _validate_response_config
+    if not config or CORE.data.get(DOMAIN, {}).get(CONF_CAPTURE_RESPONSE, False):
+        return base + ["json"]
+
+    return base
+
+
 api_ns = cg.esphome_ns.namespace("api")
 APIServer = api_ns.class_("APIServer", cg.Component, cg.Controller)
 HomeAssistantServiceCallAction = api_ns.class_(
     "HomeAssistantServiceCallAction", automation.Action
 )
+ActionResponse = api_ns.class_("ActionResponse")
+HomeAssistantActionResponseTrigger = api_ns.class_(
+    "HomeAssistantActionResponseTrigger", automation.Trigger
+)
 APIConnectedCondition = api_ns.class_("APIConnectedCondition", Condition)
 
 UserServiceTrigger = api_ns.class_("UserServiceTrigger", automation.Trigger)
@@ -50,10 +71,12 @@ SERVICE_ARG_NATIVE_TYPES = {
     "int": cg.int32,
     "float": float,
     "string": cg.std_string,
-    "bool[]": cg.std_vector.template(bool),
-    "int[]": cg.std_vector.template(cg.int32),
-    "float[]": cg.std_vector.template(float),
-    "string[]": cg.std_vector.template(cg.std_string),
+    "bool[]": cg.FixedVector.template(bool).operator("const").operator("ref"),
+    "int[]": cg.FixedVector.template(cg.int32).operator("const").operator("ref"),
+    "float[]": cg.FixedVector.template(float).operator("const").operator("ref"),
+    "string[]": cg.FixedVector.template(cg.std_string)
+    .operator("const")
+    .operator("ref"),
 }
 CONF_ENCRYPTION = "encryption"
 CONF_BATCH_DELAY = "batch_delay"
@@ -134,6 +157,17 @@ def _validate_api_config(config: ConfigType) -> ConfigType:
     return config
 
 
+def _consume_api_sockets(config: ConfigType) -> ConfigType:
+    """Register socket needs for API component."""
+    from esphome.components import socket
+
+    # API needs 1 listening socket + typically 3 concurrent client connections
+    # (not max_connections, which is the upper limit rarely reached)
+    sockets_needed = 1 + 3
+    socket.consume_sockets(sockets_needed, "api")(config)
+    return config
+
+
 CONFIG_SCHEMA = cv.All(
     cv.Schema(
         {
@@ -201,6 +235,7 @@ CONFIG_SCHEMA = cv.All(
     ).extend(cv.COMPONENT_SCHEMA),
     cv.rename_key(CONF_SERVICES, CONF_ACTIONS),
     _validate_api_config,
+    _consume_api_sockets,
 )
 
 
@@ -209,6 +244,9 @@ async def to_code(config):
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
 
+    # Track controller registration for StaticVector sizing
+    CORE.register_controller()
+
     cg.add(var.set_port(config[CONF_PORT]))
     if config[CONF_PASSWORD]:
         cg.add_define("USE_API_PASSWORD")
@@ -225,6 +263,10 @@ async def to_code(config):
     if config.get(CONF_ACTIONS) or config[CONF_CUSTOM_SERVICES]:
         cg.add_define("USE_API_SERVICES")
 
+    # Set USE_API_CUSTOM_SERVICES if external components need dynamic service registration
+    if config[CONF_CUSTOM_SERVICES]:
+        cg.add_define("USE_API_CUSTOM_SERVICES")
+
     if config[CONF_HOMEASSISTANT_SERVICES]:
         cg.add_define("USE_API_HOMEASSISTANT_SERVICES")
 
@@ -232,6 +274,8 @@ async def to_code(config):
         cg.add_define("USE_API_HOMEASSISTANT_STATES")
 
     if actions := config.get(CONF_ACTIONS, []):
+        # Collect all triggers first, then register all at once with initializer_list
+        triggers: list[cg.Pvariable] = []
         for conf in actions:
             template_args = []
             func_args = []
@@ -245,8 +289,10 @@ async def to_code(config):
             trigger = cg.new_Pvariable(
                 conf[CONF_TRIGGER_ID], templ, conf[CONF_ACTION], service_arg_names
             )
-            cg.add(var.register_user_service(trigger))
+            triggers.append(trigger)
             await automation.build_automation(trigger, func_args, conf)
+        # Register all services at once - single allocation, no reallocations
+        cg.add(var.initialize_user_services(triggers))
 
     if CONF_ON_CLIENT_CONNECTED in config:
         cg.add_define("USE_API_CLIENT_CONNECTED_TRIGGER")
@@ -288,6 +334,29 @@ async def to_code(config):
 KEY_VALUE_SCHEMA = cv.Schema({cv.string: cv.templatable(cv.string_strict)})
 
 
+def _validate_response_config(config: ConfigType) -> ConfigType:
+    # Validate dependencies:
+    # - response_template requires capture_response: true
+    # - capture_response: true requires on_success
+    if CONF_RESPONSE_TEMPLATE in config and not config[CONF_CAPTURE_RESPONSE]:
+        raise cv.Invalid(
+            f"`{CONF_RESPONSE_TEMPLATE}` requires `{CONF_CAPTURE_RESPONSE}: true` to be set.",
+            path=[CONF_RESPONSE_TEMPLATE],
+        )
+
+    if config[CONF_CAPTURE_RESPONSE] and CONF_ON_SUCCESS not in config:
+        raise cv.Invalid(
+            f"`{CONF_CAPTURE_RESPONSE}: true` requires `{CONF_ON_SUCCESS}` to be set.",
+            path=[CONF_CAPTURE_RESPONSE],
+        )
+
+    # Track if any action uses capture_response for AUTO_LOAD
+    if config[CONF_CAPTURE_RESPONSE]:
+        CORE.data.setdefault(DOMAIN, {})[CONF_CAPTURE_RESPONSE] = True
+
+    return config
+
+
 HOMEASSISTANT_ACTION_ACTION_SCHEMA = cv.All(
     cv.Schema(
         {
@@ -303,10 +372,15 @@ HOMEASSISTANT_ACTION_ACTION_SCHEMA = cv.All(
             cv.Optional(CONF_VARIABLES, default={}): cv.Schema(
                 {cv.string: cv.returning_lambda}
             ),
+            cv.Optional(CONF_RESPONSE_TEMPLATE): cv.templatable(cv.string),
+            cv.Optional(CONF_CAPTURE_RESPONSE, default=False): cv.boolean,
+            cv.Optional(CONF_ON_SUCCESS): automation.validate_automation(single=True),
+            cv.Optional(CONF_ON_ERROR): automation.validate_automation(single=True),
         }
     ),
     cv.has_exactly_one_key(CONF_SERVICE, CONF_ACTION),
     cv.rename_key(CONF_SERVICE, CONF_ACTION),
+    _validate_response_config,
 )
 
 
@@ -320,21 +394,67 @@ HOMEASSISTANT_ACTION_ACTION_SCHEMA = cv.All(
     HomeAssistantServiceCallAction,
     HOMEASSISTANT_ACTION_ACTION_SCHEMA,
 )
-async def homeassistant_service_to_code(config, action_id, template_arg, args):
+async def homeassistant_service_to_code(
+    config: ConfigType,
+    action_id: ID,
+    template_arg: cg.TemplateArguments,
+    args: TemplateArgsType,
+):
     cg.add_define("USE_API_HOMEASSISTANT_SERVICES")
     serv = await cg.get_variable(config[CONF_ID])
     var = cg.new_Pvariable(action_id, template_arg, serv, False)
     templ = await cg.templatable(config[CONF_ACTION], args, None)
     cg.add(var.set_service(templ))
+
+    # Initialize FixedVectors with exact sizes from config
+    cg.add(var.init_data(len(config[CONF_DATA])))
     for key, value in config[CONF_DATA].items():
         templ = await cg.templatable(value, args, None)
         cg.add(var.add_data(key, templ))
+
+    cg.add(var.init_data_template(len(config[CONF_DATA_TEMPLATE])))
     for key, value in config[CONF_DATA_TEMPLATE].items():
         templ = await cg.templatable(value, args, None)
         cg.add(var.add_data_template(key, templ))
+
+    cg.add(var.init_variables(len(config[CONF_VARIABLES])))
     for key, value in config[CONF_VARIABLES].items():
         templ = await cg.templatable(value, args, None)
         cg.add(var.add_variable(key, templ))
+
+    if on_error := config.get(CONF_ON_ERROR):
+        cg.add_define("USE_API_HOMEASSISTANT_ACTION_RESPONSES")
+        cg.add_define("USE_API_HOMEASSISTANT_ACTION_RESPONSES_ERRORS")
+        cg.add(var.set_wants_status())
+        await automation.build_automation(
+            var.get_error_trigger(),
+            [(cg.std_string, "error"), *args],
+            on_error,
+        )
+
+    if on_success := config.get(CONF_ON_SUCCESS):
+        cg.add_define("USE_API_HOMEASSISTANT_ACTION_RESPONSES")
+        cg.add(var.set_wants_status())
+        if config[CONF_CAPTURE_RESPONSE]:
+            cg.add(var.set_wants_response())
+            cg.add_define("USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON")
+            await automation.build_automation(
+                var.get_success_trigger_with_response(),
+                [(cg.JsonObjectConst, "response"), *args],
+                on_success,
+            )
+
+            if response_template := config.get(CONF_RESPONSE_TEMPLATE):
+                templ = await cg.templatable(response_template, args, cg.std_string)
+                cg.add(var.set_response_template(templ))
+
+        else:
+            await automation.build_automation(
+                var.get_success_trigger(),
+                args,
+                on_success,
+            )
+
     return var
 
 
@@ -370,15 +490,23 @@ async def homeassistant_event_to_code(config, action_id, template_arg, args):
     var = cg.new_Pvariable(action_id, template_arg, serv, True)
     templ = await cg.templatable(config[CONF_EVENT], args, None)
     cg.add(var.set_service(templ))
+
+    # Initialize FixedVectors with exact sizes from config
+    cg.add(var.init_data(len(config[CONF_DATA])))
     for key, value in config[CONF_DATA].items():
         templ = await cg.templatable(value, args, None)
         cg.add(var.add_data(key, templ))
+
+    cg.add(var.init_data_template(len(config[CONF_DATA_TEMPLATE])))
     for key, value in config[CONF_DATA_TEMPLATE].items():
         templ = await cg.templatable(value, args, None)
         cg.add(var.add_data_template(key, templ))
+
+    cg.add(var.init_variables(len(config[CONF_VARIABLES])))
     for key, value in config[CONF_VARIABLES].items():
         templ = await cg.templatable(value, args, None)
         cg.add(var.add_variable(key, templ))
+
     return var
 
 
@@ -401,6 +529,8 @@ async def homeassistant_tag_scanned_to_code(config, action_id, template_arg, arg
     serv = await cg.get_variable(config[CONF_ID])
     var = cg.new_Pvariable(action_id, template_arg, serv, True)
     cg.add(var.set_service("esphome.tag_scanned"))
+    # Initialize FixedVector with exact size (1 data field)
+    cg.add(var.init_data(1))
     templ = await cg.templatable(config[CONF_TAG], args, cg.std_string)
     cg.add(var.add_data("tag_id", templ))
     return var

esphome/components/api/api.proto

@@ -425,7 +425,7 @@ message ListEntitiesFanResponse {
   bool disabled_by_default = 9;
   string icon = 10 [(field_ifdef) = "USE_ENTITY_ICON"];
   EntityCategory entity_category = 11;
-  repeated string supported_preset_modes = 12 [(container_pointer) = "std::set"];
+  repeated string supported_preset_modes = 12 [(container_pointer_no_template) = "std::vector<const char *>"];
   uint32 device_id = 13 [(field_ifdef) = "USE_DEVICES"];
 }
 // Deprecated in API version 1.6 - only used in deprecated fields
@@ -506,7 +506,7 @@ message ListEntitiesLightResponse {
   string name = 3;
   reserved 4; // Deprecated: was string unique_id
 
-  repeated ColorMode supported_color_modes = 12 [(container_pointer) = "std::set<light::ColorMode>"];
+  repeated ColorMode supported_color_modes = 12 [(container_pointer_no_template) = "light::ColorModeMask"];
   // next four supports_* are for legacy clients, newer clients should use color modes
   // Deprecated in API version 1.6
   bool legacy_supports_brightness = 5 [deprecated=true];
@@ -776,10 +776,26 @@ message HomeassistantActionRequest {
   option (ifdef) = "USE_API_HOMEASSISTANT_SERVICES";
 
   string service = 1;
-  repeated HomeassistantServiceMap data = 2;
-  repeated HomeassistantServiceMap data_template = 3;
-  repeated HomeassistantServiceMap variables = 4;
+  repeated HomeassistantServiceMap data = 2 [(fixed_vector) = true];
+  repeated HomeassistantServiceMap data_template = 3 [(fixed_vector) = true];
+  repeated HomeassistantServiceMap variables = 4 [(fixed_vector) = true];
   bool is_event = 5;
+  uint32 call_id = 6 [(field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES"];
+  bool wants_response = 7 [(field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON"];
+  string response_template = 8 [(no_zero_copy) = true, (field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON"];
+}
+
+// Message sent by Home Assistant to ESPHome with service call response data
+message HomeassistantActionResponse {
+  option (id) = 130;
+  option (source) = SOURCE_CLIENT;
+  option (no_delay) = true;
+  option (ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES";
+
+  uint32 call_id = 1; // Matches the call_id from HomeassistantActionRequest
+  bool success = 2; // Whether the service call succeeded
+  string error_message = 3; // Error message if success = false
+  bytes response_data = 4 [(pointer_to_buffer) = true, (field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON"];
 }
 
 // ==================== IMPORT HOME ASSISTANT STATES ====================
@@ -850,7 +866,7 @@ message ListEntitiesServicesResponse {
 
   string name = 1;
   fixed32 key = 2;
-  repeated ListEntitiesServicesArgument args = 3;
+  repeated ListEntitiesServicesArgument args = 3 [(fixed_vector) = true];
 }
 message ExecuteServiceArgument {
   option (ifdef) = "USE_API_SERVICES";
@@ -860,10 +876,10 @@ message ExecuteServiceArgument {
   string string_ = 4;
   // ESPHome 1.14 (api v1.3) make int a signed value
   sint32 int_ = 5;
-  repeated bool bool_array = 6 [packed=false];
-  repeated sint32 int_array = 7 [packed=false];
-  repeated float float_array = 8 [packed=false];
-  repeated string string_array = 9;
+  repeated bool bool_array = 6 [packed=false, (fixed_vector) = true];
+  repeated sint32 int_array = 7 [packed=false, (fixed_vector) = true];
+  repeated float float_array = 8 [packed=false, (fixed_vector) = true];
+  repeated string string_array = 9 [(fixed_vector) = true];
 }
 message ExecuteServiceRequest {
   option (id) = 42;
@@ -872,7 +888,7 @@ message ExecuteServiceRequest {
   option (ifdef) = "USE_API_SERVICES";
 
   fixed32 key = 1;
-  repeated ExecuteServiceArgument args = 2;
+  repeated ExecuteServiceArgument args = 2 [(fixed_vector) = true];
 }
 
 // ==================== CAMERA ====================
@@ -971,9 +987,9 @@ message ListEntitiesClimateResponse {
   string name = 3;
   reserved 4; // Deprecated: was string unique_id
 
-  bool supports_current_temperature = 5;
-  bool supports_two_point_target_temperature = 6;
-  repeated ClimateMode supported_modes = 7 [(container_pointer) = "std::set<climate::ClimateMode>"];
+  bool supports_current_temperature = 5; // Deprecated: use feature_flags
+  bool supports_two_point_target_temperature = 6; // Deprecated: use feature_flags
+  repeated ClimateMode supported_modes = 7 [(container_pointer_no_template) = "climate::ClimateModeMask"];
   float visual_min_temperature = 8;
   float visual_max_temperature = 9;
   float visual_target_temperature_step = 10;
@@ -981,21 +997,22 @@ message ListEntitiesClimateResponse {
   // is if CLIMATE_PRESET_AWAY exists is supported_presets
   // Deprecated in API version 1.5
   bool legacy_supports_away = 11 [deprecated=true];
-  bool supports_action = 12;
-  repeated ClimateFanMode supported_fan_modes = 13 [(container_pointer) = "std::set<climate::ClimateFanMode>"];
-  repeated ClimateSwingMode supported_swing_modes = 14 [(container_pointer) = "std::set<climate::ClimateSwingMode>"];
-  repeated string supported_custom_fan_modes = 15 [(container_pointer) = "std::set"];
-  repeated ClimatePreset supported_presets = 16 [(container_pointer) = "std::set<climate::ClimatePreset>"];
-  repeated string supported_custom_presets = 17 [(container_pointer) = "std::set"];
+  bool supports_action = 12; // Deprecated: use feature_flags
+  repeated ClimateFanMode supported_fan_modes = 13 [(container_pointer_no_template) = "climate::ClimateFanModeMask"];
+  repeated ClimateSwingMode supported_swing_modes = 14 [(container_pointer_no_template) = "climate::ClimateSwingModeMask"];
+  repeated string supported_custom_fan_modes = 15 [(container_pointer_no_template) = "std::vector<const char *>"];
+  repeated ClimatePreset supported_presets = 16 [(container_pointer_no_template) = "climate::ClimatePresetMask"];
+  repeated string supported_custom_presets = 17 [(container_pointer_no_template) = "std::vector<const char *>"];
   bool disabled_by_default = 18;
   string icon = 19 [(field_ifdef) = "USE_ENTITY_ICON"];
   EntityCategory entity_category = 20;
   float visual_current_temperature_step = 21;
-  bool supports_current_humidity = 22;
-  bool supports_target_humidity = 23;
+  bool supports_current_humidity = 22; // Deprecated: use feature_flags
+  bool supports_target_humidity = 23; // Deprecated: use feature_flags
   float visual_min_humidity = 24;
   float visual_max_humidity = 25;
   uint32 device_id = 26 [(field_ifdef) = "USE_DEVICES"];
+  uint32 feature_flags = 27;
 }
 message ClimateStateResponse {
   option (id) = 47;
@@ -1126,7 +1143,7 @@ message ListEntitiesSelectResponse {
   reserved 4; // Deprecated: was string unique_id
 
   string icon = 5 [(field_ifdef) = "USE_ENTITY_ICON"];
-  repeated string options = 6 [(container_pointer) = "std::vector"];
+  repeated string options = 6 [(container_pointer_no_template) = "FixedVector<const char *>"];
   bool disabled_by_default = 7;
   EntityCategory entity_category = 8;
   uint32 device_id = 9 [(field_ifdef) = "USE_DEVICES"];
@@ -1503,7 +1520,7 @@ message BluetoothGATTCharacteristic {
   repeated uint64 uuid = 1 [(fixed_array_size) = 2, (fixed_array_skip_zero) = true];
   uint32 handle = 2;
   uint32 properties = 3;
-  repeated BluetoothGATTDescriptor descriptors = 4;
+  repeated BluetoothGATTDescriptor descriptors = 4 [(fixed_vector) = true];
 
   // New field for efficient UUID (v1.12+)
   // Only one of uuid or short_uuid will be set.
@@ -1515,7 +1532,7 @@ message BluetoothGATTCharacteristic {
 message BluetoothGATTService {
   repeated uint64 uuid = 1 [(fixed_array_size) = 2, (fixed_array_skip_zero) = true];
   uint32 handle = 2;
-  repeated BluetoothGATTCharacteristic characteristics = 3;
+  repeated BluetoothGATTCharacteristic characteristics = 3 [(fixed_vector) = true];
 
   // New field for efficient UUID (v1.12+)
   // Only one of uuid or short_uuid will be set.
@@ -2130,7 +2147,7 @@ message ListEntitiesEventResponse {
   EntityCategory entity_category = 7;
   string device_class = 8;
 
-  repeated string event_types = 9;
+  repeated string event_types = 9 [(container_pointer_no_template) = "FixedVector<const char *>"];
   uint32 device_id = 10 [(field_ifdef) = "USE_DEVICES"];
 }
 message EventResponse {

esphome/components/api/api_connection.cpp

@@ -8,9 +8,9 @@
 #endif
 #include <cerrno>
 #include <cinttypes>
-#include <utility>
 #include <functional>
 #include <limits>
+#include <utility>
 #include "esphome/components/network/util.h"
 #include "esphome/core/application.h"
 #include "esphome/core/entity_base.h"
@@ -27,6 +27,9 @@
 #ifdef USE_BLUETOOTH_PROXY
 #include "esphome/components/bluetooth_proxy/bluetooth_proxy.h"
 #endif
+#ifdef USE_CLIMATE
+#include "esphome/components/climate/climate_mode.h"
+#endif
 #ifdef USE_VOICE_ASSISTANT
 #include "esphome/components/voice_assistant/voice_assistant.h"
 #endif
@@ -407,8 +410,8 @@ uint16_t APIConnection::try_send_fan_state(EntityBase *entity, APIConnection *co
   }
   if (traits.supports_direction())
     msg.direction = static_cast<enums::FanDirection>(fan->direction);
-  if (traits.supports_preset_modes())
-    msg.set_preset_mode(StringRef(fan->preset_mode));
+  if (traits.supports_preset_modes() && fan->has_preset_mode())
+    msg.set_preset_mode(StringRef(fan->get_preset_mode()));
   return fill_and_encode_entity_state(fan, msg, FanStateResponse::MESSAGE_TYPE, conn, remaining_size, is_single);
 }
 uint16_t APIConnection::try_send_fan_info(EntityBase *entity, APIConnection *conn, uint32_t remaining_size,
@@ -420,7 +423,7 @@ uint16_t APIConnection::try_send_fan_info(EntityBase *entity, APIConnection *con
   msg.supports_speed = traits.supports_speed();
   msg.supports_direction = traits.supports_direction();
   msg.supported_speed_count = traits.supported_speed_count();
-  msg.supported_preset_modes = &traits.supported_preset_modes_for_api_();
+  msg.supported_preset_modes = &traits.supported_preset_modes();
   return fill_and_encode_entity_info(fan, msg, ListEntitiesFanResponse::MESSAGE_TYPE, conn, remaining_size, is_single);
 }
 void APIConnection::fan_command(const FanCommandRequest &msg) {
@@ -450,7 +453,6 @@ uint16_t APIConnection::try_send_light_state(EntityBase *entity, APIConnection *
                                              bool is_single) {
   auto *light = static_cast<light::LightState *>(entity);
   LightStateResponse resp;
-  auto traits = light->get_traits();
   auto values = light->remote_values;
   auto color_mode = values.get_color_mode();
   resp.state = values.is_on();
@@ -474,7 +476,8 @@ uint16_t APIConnection::try_send_light_info(EntityBase *entity, APIConnection *c
   auto *light = static_cast<light::LightState *>(entity);
   ListEntitiesLightResponse msg;
   auto traits = light->get_traits();
-  msg.supported_color_modes = &traits.get_supported_color_modes_for_api_();
+  // Pass pointer to ColorModeMask so the iterator can encode actual ColorMode enum values
+  msg.supported_color_modes = &traits.get_supported_color_modes();
   if (traits.supports_color_capability(light::ColorCapability::COLOR_TEMPERATURE) ||
       traits.supports_color_capability(light::ColorCapability::COLD_WARM_WHITE)) {
     msg.min_mireds = traits.get_min_mireds();
@@ -483,7 +486,7 @@ uint16_t APIConnection::try_send_light_info(EntityBase *entity, APIConnection *c
   if (light->supports_effects()) {
     msg.effects.emplace_back("None");
     for (auto *effect : light->get_effects()) {
-      msg.effects.push_back(effect->get_name());
+      msg.effects.emplace_back(effect->get_name());
     }
   }
   return fill_and_encode_entity_info(light, msg, ListEntitiesLightResponse::MESSAGE_TYPE, conn, remaining_size,
@@ -623,9 +626,10 @@ uint16_t APIConnection::try_send_climate_state(EntityBase *entity, APIConnection
   auto traits = climate->get_traits();
   resp.mode = static_cast<enums::ClimateMode>(climate->mode);
   resp.action = static_cast<enums::ClimateAction>(climate->action);
-  if (traits.get_supports_current_temperature())
+  if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_TEMPERATURE))
     resp.current_temperature = climate->current_temperature;
-  if (traits.get_supports_two_point_target_temperature()) {
+  if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE |
+                               climate::CLIMATE_REQUIRES_TWO_POINT_TARGET_TEMPERATURE)) {
     resp.target_temperature_low = climate->target_temperature_low;
     resp.target_temperature_high = climate->target_temperature_high;
   } else {
@@ -633,20 +637,20 @@ uint16_t APIConnection::try_send_climate_state(EntityBase *entity, APIConnection
   }
   if (traits.get_supports_fan_modes() && climate->fan_mode.has_value())
     resp.fan_mode = static_cast<enums::ClimateFanMode>(climate->fan_mode.value());
-  if (!traits.get_supported_custom_fan_modes().empty() && climate->custom_fan_mode.has_value()) {
-    resp.set_custom_fan_mode(StringRef(climate->custom_fan_mode.value()));
+  if (!traits.get_supported_custom_fan_modes().empty() && climate->has_custom_fan_mode()) {
+    resp.set_custom_fan_mode(StringRef(climate->get_custom_fan_mode()));
   }
   if (traits.get_supports_presets() && climate->preset.has_value()) {
     resp.preset = static_cast<enums::ClimatePreset>(climate->preset.value());
   }
-  if (!traits.get_supported_custom_presets().empty() && climate->custom_preset.has_value()) {
-    resp.set_custom_preset(StringRef(climate->custom_preset.value()));
+  if (!traits.get_supported_custom_presets().empty() && climate->has_custom_preset()) {
+    resp.set_custom_preset(StringRef(climate->get_custom_preset()));
   }
   if (traits.get_supports_swing_modes())
     resp.swing_mode = static_cast<enums::ClimateSwingMode>(climate->swing_mode);
-  if (traits.get_supports_current_humidity())
+  if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_HUMIDITY))
     resp.current_humidity = climate->current_humidity;
-  if (traits.get_supports_target_humidity())
+  if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_TARGET_HUMIDITY))
     resp.target_humidity = climate->target_humidity;
   return fill_and_encode_entity_state(climate, resp, ClimateStateResponse::MESSAGE_TYPE, conn, remaining_size,
                                       is_single);
@@ -656,23 +660,27 @@ uint16_t APIConnection::try_send_climate_info(EntityBase *entity, APIConnection
   auto *climate = static_cast<climate::Climate *>(entity);
   ListEntitiesClimateResponse msg;
   auto traits = climate->get_traits();
-  msg.supports_current_temperature = traits.get_supports_current_temperature();
-  msg.supports_current_humidity = traits.get_supports_current_humidity();
-  msg.supports_two_point_target_temperature = traits.get_supports_two_point_target_temperature();
-  msg.supports_target_humidity = traits.get_supports_target_humidity();
-  msg.supported_modes = &traits.get_supported_modes_for_api_();
+  // Flags set for backward compatibility, deprecated in 2025.11.0
+  msg.supports_current_temperature = traits.has_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_TEMPERATURE);
+  msg.supports_current_humidity = traits.has_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_HUMIDITY);
+  msg.supports_two_point_target_temperature = traits.has_feature_flags(
+      climate::CLIMATE_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE | climate::CLIMATE_REQUIRES_TWO_POINT_TARGET_TEMPERATURE);
+  msg.supports_target_humidity = traits.has_feature_flags(climate::CLIMATE_SUPPORTS_TARGET_HUMIDITY);
+  msg.supports_action = traits.has_feature_flags(climate::CLIMATE_SUPPORTS_ACTION);
+  // Current feature flags and other supported parameters
+  msg.feature_flags = traits.get_feature_flags();
+  msg.supported_modes = &traits.get_supported_modes();
   msg.visual_min_temperature = traits.get_visual_min_temperature();
   msg.visual_max_temperature = traits.get_visual_max_temperature();
   msg.visual_target_temperature_step = traits.get_visual_target_temperature_step();
   msg.visual_current_temperature_step = traits.get_visual_current_temperature_step();
   msg.visual_min_humidity = traits.get_visual_min_humidity();
   msg.visual_max_humidity = traits.get_visual_max_humidity();
-  msg.supports_action = traits.get_supports_action();
-  msg.supported_fan_modes = &traits.get_supported_fan_modes_for_api_();
-  msg.supported_custom_fan_modes = &traits.get_supported_custom_fan_modes_for_api_();
-  msg.supported_presets = &traits.get_supported_presets_for_api_();
-  msg.supported_custom_presets = &traits.get_supported_custom_presets_for_api_();
-  msg.supported_swing_modes = &traits.get_supported_swing_modes_for_api_();
+  msg.supported_fan_modes = &traits.get_supported_fan_modes();
+  msg.supported_custom_fan_modes = &traits.get_supported_custom_fan_modes();
+  msg.supported_presets = &traits.get_supported_presets();
+  msg.supported_custom_presets = &traits.get_supported_custom_presets();
+  msg.supported_swing_modes = &traits.get_supported_swing_modes();
   return fill_and_encode_entity_info(climate, msg, ListEntitiesClimateResponse::MESSAGE_TYPE, conn, remaining_size,
                                      is_single);
 }
@@ -869,7 +877,7 @@ uint16_t APIConnection::try_send_select_state(EntityBase *entity, APIConnection
                                               bool is_single) {
   auto *select = static_cast<select::Select *>(entity);
   SelectStateResponse resp;
-  resp.set_state(StringRef(select->state));
+  resp.set_state(StringRef(select->current_option()));
   resp.missing_state = !select->has_state();
   return fill_and_encode_entity_state(select, resp, SelectStateResponse::MESSAGE_TYPE, conn, remaining_size, is_single);
 }
@@ -1074,13 +1082,8 @@ void APIConnection::on_get_time_response(const GetTimeResponse &value) {
     homeassistant::global_homeassistant_time->set_epoch_time(value.epoch_seconds);
 #ifdef USE_TIME_TIMEZONE
     if (value.timezone_len > 0) {
-      const std::string &current_tz = homeassistant::global_homeassistant_time->get_timezone();
-      // Compare without allocating a string
-      if (current_tz.length() != value.timezone_len ||
-          memcmp(current_tz.c_str(), value.timezone, value.timezone_len) != 0) {
-        homeassistant::global_homeassistant_time->set_timezone(
-            std::string(reinterpret_cast<const char *>(value.timezone), value.timezone_len));
-      }
+      homeassistant::global_homeassistant_time->set_timezone(reinterpret_cast<const char *>(value.timezone),
+                                                             value.timezone_len);
     }
 #endif
   }
@@ -1307,8 +1310,7 @@ uint16_t APIConnection::try_send_event_info(EntityBase *entity, APIConnection *c
   auto *event = static_cast<event::Event *>(entity);
   ListEntitiesEventResponse msg;
   msg.set_device_class(event->get_device_class_ref());
-  for (const auto &event_type : event->get_event_types())
-    msg.event_types.push_back(event_type);
+  msg.event_types = &event->get_event_types();
   return fill_and_encode_entity_info(event, msg, ListEntitiesEventResponse::MESSAGE_TYPE, conn, remaining_size,
                                      is_single);
 }
@@ -1406,7 +1408,7 @@ bool APIConnection::send_hello_response(const HelloRequest &msg) {
 
   HelloResponse resp;
   resp.api_version_major = 1;
-  resp.api_version_minor = 12;
+  resp.api_version_minor = 13;
   // Send only the version string - the client only logs this for debugging and doesn't use it otherwise
   resp.set_server_info(ESPHOME_VERSION_REF);
   resp.set_name(StringRef(App.get_name()));
@@ -1549,13 +1551,33 @@ void APIConnection::execute_service(const ExecuteServiceRequest &msg) {
   }
 }
 #endif
+
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+void APIConnection::on_homeassistant_action_response(const HomeassistantActionResponse &msg) {
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  if (msg.response_data_len > 0) {
+    this->parent_->handle_action_response(msg.call_id, msg.success, msg.error_message, msg.response_data,
+                                          msg.response_data_len);
+  } else
+#endif
+  {
+    this->parent_->handle_action_response(msg.call_id, msg.success, msg.error_message);
+  }
+};
+#endif
 #ifdef USE_API_NOISE
 bool APIConnection::send_noise_encryption_set_key_response(const NoiseEncryptionSetKeyRequest &msg) {
   NoiseEncryptionSetKeyResponse resp;
   resp.success = false;
 
   psk_t psk{};
-  if (base64_decode(msg.key, psk.data(), msg.key.size()) != psk.size()) {
+  if (msg.key.empty()) {
+    if (this->parent_->clear_noise_psk(true)) {
+      resp.success = true;
+    } else {
+      ESP_LOGW(TAG, "Failed to clear encryption key");
+    }
+  } else if (base64_decode(msg.key, psk.data(), msg.key.size()) != psk.size()) {
     ESP_LOGW(TAG, "Invalid encryption key length");
   } else if (!this->parent_->save_noise_psk(psk, true)) {
     ESP_LOGW(TAG, "Failed to save encryption key");

esphome/components/api/api_connection.h

@@ -129,7 +129,10 @@ class APIConnection final : public APIServerConnection {
       return;
     this->send_message(call, HomeassistantActionRequest::MESSAGE_TYPE);
   }
-#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  void on_homeassistant_action_response(const HomeassistantActionResponse &msg) override;
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
+#endif  // USE_API_HOMEASSISTANT_SERVICES
 #ifdef USE_BLUETOOTH_PROXY
   void subscribe_bluetooth_le_advertisements(const SubscribeBluetoothLEAdvertisementsRequest &msg) override;
   void unsubscribe_bluetooth_le_advertisements(const UnsubscribeBluetoothLEAdvertisementsRequest &msg) override;

esphome/components/api/api_frame_helper.h

@@ -18,6 +18,17 @@ namespace esphome::api {
 // uncomment to log raw packets
 //#define HELPER_LOG_PACKETS
 
+// Maximum message size limits to prevent OOM on constrained devices
+// Handshake messages are limited to a small size for security
+static constexpr uint16_t MAX_HANDSHAKE_SIZE = 128;
+
+// Data message limits vary by platform based on available memory
+#ifdef USE_ESP8266
+static constexpr uint16_t MAX_MESSAGE_SIZE = 8192;  // 8 KiB for ESP8266
+#else
+static constexpr uint16_t MAX_MESSAGE_SIZE = 32768;  // 32 KiB for ESP32 and other platforms
+#endif
+
 // Forward declaration
 struct ClientInfo;
 

esphome/components/api/api_frame_helper_noise.cpp

@@ -132,26 +132,16 @@ APIError APINoiseFrameHelper::loop() {
   return APIFrameHelper::loop();
 }
 
-/** Read a packet into the rx_buf_. If successful, stores frame data in the frame parameter
+/** Read a packet into the rx_buf_.
  *
- * @param frame: The struct to hold the frame information in.
- *   msg_start: points to the start of the payload - this pointer is only valid until the next
- *     try_receive_raw_ call
- *
- * @return 0 if a full packet is in rx_buf_
- * @return -1 if error, check errno.
+ * @return APIError::OK if a full packet is in rx_buf_
  *
  * errno EWOULDBLOCK: Packet could not be read without blocking. Try again later.
  * errno ENOMEM: Not enough memory for reading packet.
  * errno API_ERROR_BAD_INDICATOR: Bad indicator byte at start of frame.
  * errno API_ERROR_HANDSHAKE_PACKET_LEN: Packet too big for this phase.
  */
-APIError APINoiseFrameHelper::try_read_frame_(std::vector<uint8_t> *frame) {
-  if (frame == nullptr) {
-    HELPER_LOG("Bad argument for try_read_frame_");
-    return APIError::BAD_ARG;
-  }
-
+APIError APINoiseFrameHelper::try_read_frame_() {
   // read header
   if (rx_header_buf_len_ < 3) {
     // no header information yet
@@ -178,16 +168,17 @@ APIError APINoiseFrameHelper::try_read_frame_(std::vector<uint8_t> *frame) {
   // read body
   uint16_t msg_size = (((uint16_t) rx_header_buf_[1]) << 8) | rx_header_buf_[2];
 
-  if (state_ != State::DATA && msg_size > 128) {
-    // for handshake message only permit up to 128 bytes
+  // Check against size limits to prevent OOM: MAX_HANDSHAKE_SIZE for handshake, MAX_MESSAGE_SIZE for data
+  uint16_t limit = (state_ == State::DATA) ? MAX_MESSAGE_SIZE : MAX_HANDSHAKE_SIZE;
+  if (msg_size > limit) {
     state_ = State::FAILED;
-    HELPER_LOG("Bad packet len for handshake: %d", msg_size);
-    return APIError::BAD_HANDSHAKE_PACKET_LEN;
+    HELPER_LOG("Bad packet: message size %u exceeds maximum %u", msg_size, limit);
+    return (state_ == State::DATA) ? APIError::BAD_DATA_PACKET : APIError::BAD_HANDSHAKE_PACKET_LEN;
   }
 
-  // reserve space for body
-  if (rx_buf_.size() != msg_size) {
-    rx_buf_.resize(msg_size);
+  // Reserve space for body
+  if (this->rx_buf_.size() != msg_size) {
+    this->rx_buf_.resize(msg_size);
   }
 
   if (rx_buf_len_ < msg_size) {
@@ -205,12 +196,12 @@ APIError APINoiseFrameHelper::try_read_frame_(std::vector<uint8_t> *frame) {
     }
   }
 
-  LOG_PACKET_RECEIVED(rx_buf_);
-  *frame = std::move(rx_buf_);
-  // consume msg
-  rx_buf_ = {};
-  rx_buf_len_ = 0;
-  rx_header_buf_len_ = 0;
+  LOG_PACKET_RECEIVED(this->rx_buf_);
+
+  // Clear state for next frame (rx_buf_ still contains data for caller)
+  this->rx_buf_len_ = 0;
+  this->rx_header_buf_len_ = 0;
+
   return APIError::OK;
 }
 
@@ -232,18 +223,17 @@ APIError APINoiseFrameHelper::state_action_() {
   }
   if (state_ == State::CLIENT_HELLO) {
     // waiting for client hello
-    std::vector<uint8_t> frame;
-    aerr = try_read_frame_(&frame);
+    aerr = this->try_read_frame_();
     if (aerr != APIError::OK) {
       return handle_handshake_frame_error_(aerr);
     }
     // ignore contents, may be used in future for flags
     // Resize for: existing prologue + 2 size bytes + frame data
-    size_t old_size = prologue_.size();
-    prologue_.resize(old_size + 2 + frame.size());
-    prologue_[old_size] = (uint8_t) (frame.size() >> 8);
-    prologue_[old_size + 1] = (uint8_t) frame.size();
-    std::memcpy(prologue_.data() + old_size + 2, frame.data(), frame.size());
+    size_t old_size = this->prologue_.size();
+    this->prologue_.resize(old_size + 2 + this->rx_buf_.size());
+    this->prologue_[old_size] = (uint8_t) (this->rx_buf_.size() >> 8);
+    this->prologue_[old_size + 1] = (uint8_t) this->rx_buf_.size();
+    std::memcpy(this->prologue_.data() + old_size + 2, this->rx_buf_.data(), this->rx_buf_.size());
 
     state_ = State::SERVER_HELLO;
   }
@@ -252,7 +242,6 @@ APIError APINoiseFrameHelper::state_action_() {
     const std::string &name = App.get_name();
     const std::string &mac = get_mac_address();
 
-    std::vector<uint8_t> msg;
     // Calculate positions and sizes
     size_t name_len = name.size() + 1;  // including null terminator
     size_t mac_len = mac.size() + 1;    // including null terminator
@@ -260,17 +249,17 @@ APIError APINoiseFrameHelper::state_action_() {
     size_t mac_offset = name_offset + name_len;
     size_t total_size = 1 + name_len + mac_len;
 
-    msg.resize(total_size);
+    auto msg = std::make_unique<uint8_t[]>(total_size);
 
     // chosen proto
     msg[0] = 0x01;
 
     // node name, terminated by null byte
-    std::memcpy(msg.data() + name_offset, name.c_str(), name_len);
+    std::memcpy(msg.get() + name_offset, name.c_str(), name_len);
     // node mac, terminated by null byte
-    std::memcpy(msg.data() + mac_offset, mac.c_str(), mac_len);
+    std::memcpy(msg.get() + mac_offset, mac.c_str(), mac_len);
 
-    aerr = write_frame_(msg.data(), msg.size());
+    aerr = write_frame_(msg.get(), total_size);
     if (aerr != APIError::OK)
       return aerr;
 
@@ -285,24 +274,23 @@ APIError APINoiseFrameHelper::state_action_() {
     int action = noise_handshakestate_get_action(handshake_);
     if (action == NOISE_ACTION_READ_MESSAGE) {
       // waiting for handshake msg
-      std::vector<uint8_t> frame;
-      aerr = try_read_frame_(&frame);
+      aerr = this->try_read_frame_();
       if (aerr != APIError::OK) {
         return handle_handshake_frame_error_(aerr);
       }
 
-      if (frame.empty()) {
+      if (this->rx_buf_.empty()) {
         send_explicit_handshake_reject_(LOG_STR("Empty handshake message"));
         return APIError::BAD_HANDSHAKE_ERROR_BYTE;
-      } else if (frame[0] != 0x00) {
-        HELPER_LOG("Bad handshake error byte: %u", frame[0]);
+      } else if (this->rx_buf_[0] != 0x00) {
+        HELPER_LOG("Bad handshake error byte: %u", this->rx_buf_[0]);
         send_explicit_handshake_reject_(LOG_STR("Bad handshake error byte"));
         return APIError::BAD_HANDSHAKE_ERROR_BYTE;
       }
 
       NoiseBuffer mbuf;
       noise_buffer_init(mbuf);
-      noise_buffer_set_input(mbuf, frame.data() + 1, frame.size() - 1);
+      noise_buffer_set_input(mbuf, this->rx_buf_.data() + 1, this->rx_buf_.size() - 1);
       err = noise_handshakestate_read_message(handshake_, &mbuf, nullptr);
       if (err != 0) {
         // Special handling for MAC failure
@@ -350,64 +338,62 @@ void APINoiseFrameHelper::send_explicit_handshake_reject_(const LogString *reaso
 #ifdef USE_STORE_LOG_STR_IN_FLASH
   // On ESP8266 with flash strings, we need to use PROGMEM-aware functions
   size_t reason_len = strlen_P(reinterpret_cast<PGM_P>(reason));
-  std::vector<uint8_t> data;
-  data.resize(reason_len + 1);
+  size_t data_size = reason_len + 1;
+  auto data = std::make_unique<uint8_t[]>(data_size);
   data[0] = 0x01;  // failure
 
   // Copy error message from PROGMEM
   if (reason_len > 0) {
-    memcpy_P(data.data() + 1, reinterpret_cast<PGM_P>(reason), reason_len);
+    memcpy_P(data.get() + 1, reinterpret_cast<PGM_P>(reason), reason_len);
   }
 #else
   // Normal memory access
   const char *reason_str = LOG_STR_ARG(reason);
   size_t reason_len = strlen(reason_str);
-  std::vector<uint8_t> data;
-  data.resize(reason_len + 1);
+  size_t data_size = reason_len + 1;
+  auto data = std::make_unique<uint8_t[]>(data_size);
   data[0] = 0x01;  // failure
 
   // Copy error message in bulk
   if (reason_len > 0) {
-    std::memcpy(data.data() + 1, reason_str, reason_len);
+    std::memcpy(data.get() + 1, reason_str, reason_len);
   }
 #endif
 
   // temporarily remove failed state
   auto orig_state = state_;
   state_ = State::EXPLICIT_REJECT;
-  write_frame_(data.data(), data.size());
+  write_frame_(data.get(), data_size);
   state_ = orig_state;
 }
 APIError APINoiseFrameHelper::read_packet(ReadPacketBuffer *buffer) {
-  int err;
-  APIError aerr;
-  aerr = state_action_();
+  APIError aerr = this->state_action_();
   if (aerr != APIError::OK) {
     return aerr;
   }
 
-  if (state_ != State::DATA) {
+  if (this->state_ != State::DATA) {
     return APIError::WOULD_BLOCK;
   }
 
-  std::vector<uint8_t> frame;
-  aerr = try_read_frame_(&frame);
+  aerr = this->try_read_frame_();
   if (aerr != APIError::OK)
     return aerr;
 
   NoiseBuffer mbuf;
   noise_buffer_init(mbuf);
-  noise_buffer_set_inout(mbuf, frame.data(), frame.size(), frame.size());
-  err = noise_cipherstate_decrypt(recv_cipher_, &mbuf);
+  noise_buffer_set_inout(mbuf, this->rx_buf_.data(), this->rx_buf_.size(), this->rx_buf_.size());
+  int err = noise_cipherstate_decrypt(this->recv_cipher_, &mbuf);
   APIError decrypt_err =
       handle_noise_error_(err, LOG_STR("noise_cipherstate_decrypt"), APIError::CIPHERSTATE_DECRYPT_FAILED);
-  if (decrypt_err != APIError::OK)
+  if (decrypt_err != APIError::OK) {
     return decrypt_err;
+  }
 
   uint16_t msg_size = mbuf.size;
-  uint8_t *msg_data = frame.data();
+  uint8_t *msg_data = this->rx_buf_.data();
   if (msg_size < 4) {
-    state_ = State::FAILED;
+    this->state_ = State::FAILED;
     HELPER_LOG("Bad data packet: size %d too short", msg_size);
     return APIError::BAD_DATA_PACKET;
   }
@@ -415,12 +401,12 @@ APIError APINoiseFrameHelper::read_packet(ReadPacketBuffer *buffer) {
   uint16_t type = (((uint16_t) msg_data[0]) << 8) | msg_data[1];
   uint16_t data_len = (((uint16_t) msg_data[2]) << 8) | msg_data[3];
   if (data_len > msg_size - 4) {
-    state_ = State::FAILED;
+    this->state_ = State::FAILED;
     HELPER_LOG("Bad data packet: data_len %u greater than msg_size %u", data_len, msg_size);
     return APIError::BAD_DATA_PACKET;
   }
 
-  buffer->container = std::move(frame);
+  buffer->container = std::move(this->rx_buf_);
   buffer->data_offset = 4;
   buffer->data_len = data_len;
   buffer->type = type;
@@ -448,8 +434,7 @@ APIError APINoiseFrameHelper::write_protobuf_packets(ProtoWriteBuffer buffer, st
     return APIError::OK;
   }
 
-  std::vector<uint8_t> *raw_buffer = buffer.get_buffer();
-  uint8_t *buffer_data = raw_buffer->data();  // Cache buffer pointer
+  uint8_t *buffer_data = buffer.get_buffer()->data();
 
   this->reusable_iovs_.clear();
   this->reusable_iovs_.reserve(packets.size());

esphome/components/api/api_frame_helper_noise.h

@@ -28,7 +28,7 @@ class APINoiseFrameHelper final : public APIFrameHelper {
 
  protected:
   APIError state_action_();
-  APIError try_read_frame_(std::vector<uint8_t> *frame);
+  APIError try_read_frame_();
   APIError write_frame_(const uint8_t *data, uint16_t len);
   APIError init_handshake_();
   APIError check_handshake_finished_();

esphome/components/api/api_frame_helper_plaintext.cpp

@@ -47,21 +47,13 @@ APIError APIPlaintextFrameHelper::loop() {
   return APIFrameHelper::loop();
 }
 
-/** Read a packet into the rx_buf_. If successful, stores frame data in the frame parameter
- *
- * @param frame: The struct to hold the frame information in.
- *   msg: store the parsed frame in that struct
+/** Read a packet into the rx_buf_.
  *
  * @return See APIError
  *
  * error API_ERROR_BAD_INDICATOR: Bad indicator byte at start of frame.
  */
-APIError APIPlaintextFrameHelper::try_read_frame_(std::vector<uint8_t> *frame) {
-  if (frame == nullptr) {
-    HELPER_LOG("Bad argument for try_read_frame_");
-    return APIError::BAD_ARG;
-  }
-
+APIError APIPlaintextFrameHelper::try_read_frame_() {
   // read header
   while (!rx_header_parsed_) {
     // Now that we know when the socket is ready, we can read up to 3 bytes
@@ -123,10 +115,10 @@ APIError APIPlaintextFrameHelper::try_read_frame_(std::vector<uint8_t> *frame) {
       continue;
     }
 
-    if (msg_size_varint->as_uint32() > std::numeric_limits<uint16_t>::max()) {
+    if (msg_size_varint->as_uint32() > MAX_MESSAGE_SIZE) {
       state_ = State::FAILED;
       HELPER_LOG("Bad packet: message size %" PRIu32 " exceeds maximum %u", msg_size_varint->as_uint32(),
-                 std::numeric_limits<uint16_t>::max());
+                 MAX_MESSAGE_SIZE);
       return APIError::BAD_DATA_PACKET;
     }
     rx_header_parsed_len_ = msg_size_varint->as_uint16();
@@ -150,9 +142,9 @@ APIError APIPlaintextFrameHelper::try_read_frame_(std::vector<uint8_t> *frame) {
   }
   // header reading done
 
-  // reserve space for body
-  if (rx_buf_.size() != rx_header_parsed_len_) {
-    rx_buf_.resize(rx_header_parsed_len_);
+  // Reserve space for body
+  if (this->rx_buf_.size() != this->rx_header_parsed_len_) {
+    this->rx_buf_.resize(this->rx_header_parsed_len_);
   }
 
   if (rx_buf_len_ < rx_header_parsed_len_) {
@@ -170,24 +162,22 @@ APIError APIPlaintextFrameHelper::try_read_frame_(std::vector<uint8_t> *frame) {
     }
   }
 
-  LOG_PACKET_RECEIVED(rx_buf_);
-  *frame = std::move(rx_buf_);
-  // consume msg
-  rx_buf_ = {};
-  rx_buf_len_ = 0;
-  rx_header_buf_pos_ = 0;
-  rx_header_parsed_ = false;
+  LOG_PACKET_RECEIVED(this->rx_buf_);
+
+  // Clear state for next frame (rx_buf_ still contains data for caller)
+  this->rx_buf_len_ = 0;
+  this->rx_header_buf_pos_ = 0;
+  this->rx_header_parsed_ = false;
+
   return APIError::OK;
 }
-APIError APIPlaintextFrameHelper::read_packet(ReadPacketBuffer *buffer) {
-  APIError aerr;
 
-  if (state_ != State::DATA) {
+APIError APIPlaintextFrameHelper::read_packet(ReadPacketBuffer *buffer) {
+  if (this->state_ != State::DATA) {
     return APIError::WOULD_BLOCK;
   }
 
-  std::vector<uint8_t> frame;
-  aerr = try_read_frame_(&frame);
+  APIError aerr = this->try_read_frame_();
   if (aerr != APIError::OK) {
     if (aerr == APIError::BAD_INDICATOR) {
       // Make sure to tell the remote that we don't
@@ -220,10 +210,10 @@ APIError APIPlaintextFrameHelper::read_packet(ReadPacketBuffer *buffer) {
     return aerr;
   }
 
-  buffer->container = std::move(frame);
+  buffer->container = std::move(this->rx_buf_);
   buffer->data_offset = 0;
-  buffer->data_len = rx_header_parsed_len_;
-  buffer->type = rx_header_parsed_type_;
+  buffer->data_len = this->rx_header_parsed_len_;
+  buffer->type = this->rx_header_parsed_type_;
   return APIError::OK;
 }
 APIError APIPlaintextFrameHelper::write_protobuf_packet(uint8_t type, ProtoWriteBuffer buffer) {
@@ -240,8 +230,7 @@ APIError APIPlaintextFrameHelper::write_protobuf_packets(ProtoWriteBuffer buffer
     return APIError::OK;
   }
 
-  std::vector<uint8_t> *raw_buffer = buffer.get_buffer();
-  uint8_t *buffer_data = raw_buffer->data();  // Cache buffer pointer
+  uint8_t *buffer_data = buffer.get_buffer()->data();
 
   this->reusable_iovs_.clear();
   this->reusable_iovs_.reserve(packets.size());

esphome/components/api/api_frame_helper_plaintext.h

@@ -24,7 +24,7 @@ class APIPlaintextFrameHelper final : public APIFrameHelper {
   APIError write_protobuf_packets(ProtoWriteBuffer buffer, std::span<const PacketInfo> packets) override;
 
  protected:
-  APIError try_read_frame_(std::vector<uint8_t> *frame);
+  APIError try_read_frame_();
 
   // Group 2-byte aligned types
   uint16_t rx_header_parsed_type_ = 0;

esphome/components/api/api_options.proto

@@ -64,4 +64,20 @@ extend google.protobuf.FieldOptions {
     // This is typically done through methods returning const T& or special accessor
     // methods like get_options() or supported_modes_for_api_().
     optional string container_pointer = 50001;
+
+    // fixed_vector: Use FixedVector instead of std::vector for repeated fields
+    // When set, the repeated field will use FixedVector<T> which requires calling
+    // init(size) before adding elements. This eliminates std::vector template overhead
+    // and is ideal when the exact size is known before populating the array.
+    optional bool fixed_vector = 50013 [default=false];
+
+    // container_pointer_no_template: Use a non-template container type for repeated fields
+    // Similar to container_pointer, but for containers that don't take template parameters.
+    // The container type is used as-is without appending element type.
+    // The container must have:
+    // - begin() and end() methods returning iterators
+    // - empty() method
+    // Example: [(container_pointer_no_template) = "light::ColorModeMask"]
+    //   generates: const light::ColorModeMask *supported_color_modes{};
+    optional string container_pointer_no_template = 50014;
 }

esphome/components/api/api_pb2.cpp

@@ -355,8 +355,8 @@ void ListEntitiesFanResponse::encode(ProtoWriteBuffer buffer) const {
   buffer.encode_string(10, this->icon_ref_);
 #endif
   buffer.encode_uint32(11, static_cast<uint32_t>(this->entity_category));
-  for (const auto &it : *this->supported_preset_modes) {
-    buffer.encode_string(12, it, true);
+  for (const char *it : *this->supported_preset_modes) {
+    buffer.encode_string(12, it, strlen(it), true);
   }
 #ifdef USE_DEVICES
   buffer.encode_uint32(13, this->device_id);
@@ -376,8 +376,8 @@ void ListEntitiesFanResponse::calculate_size(ProtoSize &size) const {
 #endif
   size.add_uint32(1, static_cast<uint32_t>(this->entity_category));
   if (!this->supported_preset_modes->empty()) {
-    for (const auto &it : *this->supported_preset_modes) {
-      size.add_length_force(1, it.size());
+    for (const char *it : *this->supported_preset_modes) {
+      size.add_length_force(1, strlen(it));
     }
   }
 #ifdef USE_DEVICES
@@ -884,6 +884,15 @@ void HomeassistantActionRequest::encode(ProtoWriteBuffer buffer) const {
     buffer.encode_message(4, it, true);
   }
   buffer.encode_bool(5, this->is_event);
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  buffer.encode_uint32(6, this->call_id);
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  buffer.encode_bool(7, this->wants_response);
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  buffer.encode_string(8, this->response_template);
+#endif
 }
 void HomeassistantActionRequest::calculate_size(ProtoSize &size) const {
   size.add_length(1, this->service_ref_.size());
@@ -891,6 +900,48 @@ void HomeassistantActionRequest::calculate_size(ProtoSize &size) const {
   size.add_repeated_message(1, this->data_template);
   size.add_repeated_message(1, this->variables);
   size.add_bool(1, this->is_event);
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  size.add_uint32(1, this->call_id);
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  size.add_bool(1, this->wants_response);
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  size.add_length(1, this->response_template.size());
+#endif
+}
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+bool HomeassistantActionResponse::decode_varint(uint32_t field_id, ProtoVarInt value) {
+  switch (field_id) {
+    case 1:
+      this->call_id = value.as_uint32();
+      break;
+    case 2:
+      this->success = value.as_bool();
+      break;
+    default:
+      return false;
+  }
+  return true;
+}
+bool HomeassistantActionResponse::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
+  switch (field_id) {
+    case 3:
+      this->error_message = value.as_string();
+      break;
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+    case 4: {
+      // Use raw data directly to avoid allocation
+      this->response_data = value.data();
+      this->response_data_len = value.size();
+      break;
+    }
+#endif
+    default:
+      return false;
+  }
+  return true;
 }
 #endif
 #ifdef USE_API_HOMEASSISTANT_STATES
@@ -1013,6 +1064,17 @@ bool ExecuteServiceArgument::decode_32bit(uint32_t field_id, Proto32Bit value) {
   }
   return true;
 }
+void ExecuteServiceArgument::decode(const uint8_t *buffer, size_t length) {
+  uint32_t count_bool_array = ProtoDecodableMessage::count_repeated_field(buffer, length, 6);
+  this->bool_array.init(count_bool_array);
+  uint32_t count_int_array = ProtoDecodableMessage::count_repeated_field(buffer, length, 7);
+  this->int_array.init(count_int_array);
+  uint32_t count_float_array = ProtoDecodableMessage::count_repeated_field(buffer, length, 8);
+  this->float_array.init(count_float_array);
+  uint32_t count_string_array = ProtoDecodableMessage::count_repeated_field(buffer, length, 9);
+  this->string_array.init(count_string_array);
+  ProtoDecodableMessage::decode(buffer, length);
+}
 bool ExecuteServiceRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 2:
@@ -1034,6 +1096,11 @@ bool ExecuteServiceRequest::decode_32bit(uint32_t field_id, Proto32Bit value) {
   }
   return true;
 }
+void ExecuteServiceRequest::decode(const uint8_t *buffer, size_t length) {
+  uint32_t count_args = ProtoDecodableMessage::count_repeated_field(buffer, length, 2);
+  this->args.init(count_args);
+  ProtoDecodableMessage::decode(buffer, length);
+}
 #endif
 #ifdef USE_CAMERA
 void ListEntitiesCameraResponse::encode(ProtoWriteBuffer buffer) const {
@@ -1112,14 +1179,14 @@ void ListEntitiesClimateResponse::encode(ProtoWriteBuffer buffer) const {
   for (const auto &it : *this->supported_swing_modes) {
     buffer.encode_uint32(14, static_cast<uint32_t>(it), true);
   }
-  for (const auto &it : *this->supported_custom_fan_modes) {
-    buffer.encode_string(15, it, true);
+  for (const char *it : *this->supported_custom_fan_modes) {
+    buffer.encode_string(15, it, strlen(it), true);
   }
   for (const auto &it : *this->supported_presets) {
     buffer.encode_uint32(16, static_cast<uint32_t>(it), true);
   }
-  for (const auto &it : *this->supported_custom_presets) {
-    buffer.encode_string(17, it, true);
+  for (const char *it : *this->supported_custom_presets) {
+    buffer.encode_string(17, it, strlen(it), true);
   }
   buffer.encode_bool(18, this->disabled_by_default);
 #ifdef USE_ENTITY_ICON
@@ -1134,6 +1201,7 @@ void ListEntitiesClimateResponse::encode(ProtoWriteBuffer buffer) const {
 #ifdef USE_DEVICES
   buffer.encode_uint32(26, this->device_id);
 #endif
+  buffer.encode_uint32(27, this->feature_flags);
 }
 void ListEntitiesClimateResponse::calculate_size(ProtoSize &size) const {
   size.add_length(1, this->object_id_ref_.size());
@@ -1161,8 +1229,8 @@ void ListEntitiesClimateResponse::calculate_size(ProtoSize &size) const {
     }
   }
   if (!this->supported_custom_fan_modes->empty()) {
-    for (const auto &it : *this->supported_custom_fan_modes) {
-      size.add_length_force(1, it.size());
+    for (const char *it : *this->supported_custom_fan_modes) {
+      size.add_length_force(1, strlen(it));
     }
   }
   if (!this->supported_presets->empty()) {
@@ -1171,8 +1239,8 @@ void ListEntitiesClimateResponse::calculate_size(ProtoSize &size) const {
     }
   }
   if (!this->supported_custom_presets->empty()) {
-    for (const auto &it : *this->supported_custom_presets) {
-      size.add_length_force(2, it.size());
+    for (const char *it : *this->supported_custom_presets) {
+      size.add_length_force(2, strlen(it));
     }
   }
   size.add_bool(2, this->disabled_by_default);
@@ -1188,6 +1256,7 @@ void ListEntitiesClimateResponse::calculate_size(ProtoSize &size) const {
 #ifdef USE_DEVICES
   size.add_uint32(2, this->device_id);
 #endif
+  size.add_uint32(2, this->feature_flags);
 }
 void ClimateStateResponse::encode(ProtoWriteBuffer buffer) const {
   buffer.encode_fixed32(1, this->key);
@@ -1406,8 +1475,8 @@ void ListEntitiesSelectResponse::encode(ProtoWriteBuffer buffer) const {
 #ifdef USE_ENTITY_ICON
   buffer.encode_string(5, this->icon_ref_);
 #endif
-  for (const auto &it : *this->options) {
-    buffer.encode_string(6, it, true);
+  for (const char *it : *this->options) {
+    buffer.encode_string(6, it, strlen(it), true);
   }
   buffer.encode_bool(7, this->disabled_by_default);
   buffer.encode_uint32(8, static_cast<uint32_t>(this->entity_category));
@@ -1423,8 +1492,8 @@ void ListEntitiesSelectResponse::calculate_size(ProtoSize &size) const {
   size.add_length(1, this->icon_ref_.size());
 #endif
   if (!this->options->empty()) {
-    for (const auto &it : *this->options) {
-      size.add_length_force(1, it.size());
+    for (const char *it : *this->options) {
+      size.add_length_force(1, strlen(it));
     }
   }
   size.add_bool(1, this->disabled_by_default);
@@ -2808,8 +2877,8 @@ void ListEntitiesEventResponse::encode(ProtoWriteBuffer buffer) const {
   buffer.encode_bool(6, this->disabled_by_default);
   buffer.encode_uint32(7, static_cast<uint32_t>(this->entity_category));
   buffer.encode_string(8, this->device_class_ref_);
-  for (auto &it : this->event_types) {
-    buffer.encode_string(9, it, true);
+  for (const char *it : *this->event_types) {
+    buffer.encode_string(9, it, strlen(it), true);
   }
 #ifdef USE_DEVICES
   buffer.encode_uint32(10, this->device_id);
@@ -2825,9 +2894,9 @@ void ListEntitiesEventResponse::calculate_size(ProtoSize &size) const {
   size.add_bool(1, this->disabled_by_default);
   size.add_uint32(1, static_cast<uint32_t>(this->entity_category));
   size.add_length(1, this->device_class_ref_.size());
-  if (!this->event_types.empty()) {
-    for (const auto &it : this->event_types) {
-      size.add_length_force(1, it.size());
+  if (!this->event_types->empty()) {
+    for (const char *it : *this->event_types) {
+      size.add_length_force(1, strlen(it));
     }
   }
 #ifdef USE_DEVICES

esphome/components/api/api_pb2.h

@@ -725,7 +725,7 @@ class ListEntitiesFanResponse final : public InfoResponseProtoMessage {
   bool supports_speed{false};
   bool supports_direction{false};
   int32_t supported_speed_count{0};
-  const std::set<std::string> *supported_preset_modes{};
+  const std::vector<const char *> *supported_preset_modes{};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -790,7 +790,7 @@ class ListEntitiesLightResponse final : public InfoResponseProtoMessage {
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "list_entities_light_response"; }
 #endif
-  const std::set<light::ColorMode> *supported_color_modes{};
+  const light::ColorModeMask *supported_color_modes{};
   float min_mireds{0.0f};
   float max_mireds{0.0f};
   std::vector<std::string> effects{};
@@ -1104,16 +1104,25 @@ class HomeassistantServiceMap final : public ProtoMessage {
 class HomeassistantActionRequest final : public ProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 35;
-  static constexpr uint8_t ESTIMATED_SIZE = 113;
+  static constexpr uint8_t ESTIMATED_SIZE = 128;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "homeassistant_action_request"; }
 #endif
   StringRef service_ref_{};
   void set_service(const StringRef &ref) { this->service_ref_ = ref; }
-  std::vector<HomeassistantServiceMap> data{};
-  std::vector<HomeassistantServiceMap> data_template{};
-  std::vector<HomeassistantServiceMap> variables{};
+  FixedVector<HomeassistantServiceMap> data{};
+  FixedVector<HomeassistantServiceMap> data_template{};
+  FixedVector<HomeassistantServiceMap> variables{};
   bool is_event{false};
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  uint32_t call_id{0};
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  bool wants_response{false};
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  std::string response_template{};
+#endif
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -1123,6 +1132,30 @@ class HomeassistantActionRequest final : public ProtoMessage {
  protected:
 };
 #endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+class HomeassistantActionResponse final : public ProtoDecodableMessage {
+ public:
+  static constexpr uint8_t MESSAGE_TYPE = 130;
+  static constexpr uint8_t ESTIMATED_SIZE = 34;
+#ifdef HAS_PROTO_MESSAGE_DUMP
+  const char *message_name() const override { return "homeassistant_action_response"; }
+#endif
+  uint32_t call_id{0};
+  bool success{false};
+  std::string error_message{};
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  const uint8_t *response_data{nullptr};
+  uint16_t response_data_len{0};
+#endif
+#ifdef HAS_PROTO_MESSAGE_DUMP
+  void dump_to(std::string &out) const override;
+#endif
+
+ protected:
+  bool decode_length(uint32_t field_id, ProtoLengthDelimited value) override;
+  bool decode_varint(uint32_t field_id, ProtoVarInt value) override;
+};
+#endif
 #ifdef USE_API_HOMEASSISTANT_STATES
 class SubscribeHomeAssistantStatesRequest final : public ProtoMessage {
  public:
@@ -1230,7 +1263,7 @@ class ListEntitiesServicesResponse final : public ProtoMessage {
   StringRef name_ref_{};
   void set_name(const StringRef &ref) { this->name_ref_ = ref; }
   uint32_t key{0};
-  std::vector<ListEntitiesServicesArgument> args{};
+  FixedVector<ListEntitiesServicesArgument> args{};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -1246,10 +1279,11 @@ class ExecuteServiceArgument final : public ProtoDecodableMessage {
   float float_{0.0f};
   std::string string_{};
   int32_t int_{0};
-  std::vector<bool> bool_array{};
-  std::vector<int32_t> int_array{};
-  std::vector<float> float_array{};
-  std::vector<std::string> string_array{};
+  FixedVector<bool> bool_array{};
+  FixedVector<int32_t> int_array{};
+  FixedVector<float> float_array{};
+  FixedVector<std::string> string_array{};
+  void decode(const uint8_t *buffer, size_t length) override;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -1267,7 +1301,8 @@ class ExecuteServiceRequest final : public ProtoDecodableMessage {
   const char *message_name() const override { return "execute_service_request"; }
 #endif
   uint32_t key{0};
-  std::vector<ExecuteServiceArgument> args{};
+  FixedVector<ExecuteServiceArgument> args{};
+  void decode(const uint8_t *buffer, size_t length) override;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -1336,27 +1371,28 @@ class CameraImageRequest final : public ProtoDecodableMessage {
 class ListEntitiesClimateResponse final : public InfoResponseProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 46;
-  static constexpr uint8_t ESTIMATED_SIZE = 145;
+  static constexpr uint8_t ESTIMATED_SIZE = 150;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "list_entities_climate_response"; }
 #endif
   bool supports_current_temperature{false};
   bool supports_two_point_target_temperature{false};
-  const std::set<climate::ClimateMode> *supported_modes{};
+  const climate::ClimateModeMask *supported_modes{};
   float visual_min_temperature{0.0f};
   float visual_max_temperature{0.0f};
   float visual_target_temperature_step{0.0f};
   bool supports_action{false};
-  const std::set<climate::ClimateFanMode> *supported_fan_modes{};
-  const std::set<climate::ClimateSwingMode> *supported_swing_modes{};
-  const std::set<std::string> *supported_custom_fan_modes{};
-  const std::set<climate::ClimatePreset> *supported_presets{};
-  const std::set<std::string> *supported_custom_presets{};
+  const climate::ClimateFanModeMask *supported_fan_modes{};
+  const climate::ClimateSwingModeMask *supported_swing_modes{};
+  const std::vector<const char *> *supported_custom_fan_modes{};
+  const climate::ClimatePresetMask *supported_presets{};
+  const std::vector<const char *> *supported_custom_presets{};
   float visual_current_temperature_step{0.0f};
   bool supports_current_humidity{false};
   bool supports_target_humidity{false};
   float visual_min_humidity{0.0f};
   float visual_max_humidity{0.0f};
+  uint32_t feature_flags{0};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -1498,7 +1534,7 @@ class ListEntitiesSelectResponse final : public InfoResponseProtoMessage {
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "list_entities_select_response"; }
 #endif
-  const std::vector<std::string> *options{};
+  const FixedVector<const char *> *options{};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -1890,7 +1926,7 @@ class BluetoothGATTCharacteristic final : public ProtoMessage {
   std::array<uint64_t, 2> uuid{};
   uint32_t handle{0};
   uint32_t properties{0};
-  std::vector<BluetoothGATTDescriptor> descriptors{};
+  FixedVector<BluetoothGATTDescriptor> descriptors{};
   uint32_t short_uuid{0};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
@@ -1904,7 +1940,7 @@ class BluetoothGATTService final : public ProtoMessage {
  public:
   std::array<uint64_t, 2> uuid{};
   uint32_t handle{0};
-  std::vector<BluetoothGATTCharacteristic> characteristics{};
+  FixedVector<BluetoothGATTCharacteristic> characteristics{};
   uint32_t short_uuid{0};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
@@ -2752,7 +2788,7 @@ class ListEntitiesEventResponse final : public InfoResponseProtoMessage {
 #endif
   StringRef device_class_ref_{};
   void set_device_class(const StringRef &ref) { this->device_class_ref_ = ref; }
-  std::vector<std::string> event_types{};
+  const FixedVector<const char *> *event_types{};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
 #ifdef HAS_PROTO_MESSAGE_DUMP

esphome/components/api/api_pb2_dump.cpp

@@ -88,6 +88,12 @@ static void dump_field(std::string &out, const char *field_name, StringRef value
   out.append("\n");
 }
 
+static void dump_field(std::string &out, const char *field_name, const char *value, int indent = 2) {
+  append_field_prefix(out, field_name, indent);
+  out.append("'").append(value).append("'");
+  out.append("\n");
+}
+
 template<typename T> static void dump_field(std::string &out, const char *field_name, T value, int indent = 2) {
   append_field_prefix(out, field_name, indent);
   out.append(proto_enum_to_string<T>(value));
@@ -1122,6 +1128,28 @@ void HomeassistantActionRequest::dump_to(std::string &out) const {
     out.append("\n");
   }
   dump_field(out, "is_event", this->is_event);
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  dump_field(out, "call_id", this->call_id);
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  dump_field(out, "wants_response", this->wants_response);
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  dump_field(out, "response_template", this->response_template);
+#endif
+}
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+void HomeassistantActionResponse::dump_to(std::string &out) const {
+  MessageDumpHelper helper(out, "HomeassistantActionResponse");
+  dump_field(out, "call_id", this->call_id);
+  dump_field(out, "success", this->success);
+  dump_field(out, "error_message", this->error_message);
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  out.append("  response_data: ");
+  out.append(format_hex_pretty(this->response_data, this->response_data_len));
+  out.append("\n");
+#endif
 }
 #endif
 #ifdef USE_API_HOMEASSISTANT_STATES
@@ -1270,6 +1298,7 @@ void ListEntitiesClimateResponse::dump_to(std::string &out) const {
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
 #endif
+  dump_field(out, "feature_flags", this->feature_flags);
 }
 void ClimateStateResponse::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "ClimateStateResponse");
@@ -2024,7 +2053,7 @@ void ListEntitiesEventResponse::dump_to(std::string &out) const {
   dump_field(out, "disabled_by_default", this->disabled_by_default);
   dump_field(out, "entity_category", static_cast<enums::EntityCategory>(this->entity_category));
   dump_field(out, "device_class", this->device_class_ref_);
-  for (const auto &it : this->event_types) {
+  for (const auto &it : *this->event_types) {
     dump_field(out, "event_types", it, 4);
   }
 #ifdef USE_DEVICES

esphome/components/api/api_pb2_service.cpp

@@ -610,6 +610,17 @@ void APIServerConnectionBase::read_message(uint32_t msg_size, uint32_t msg_type,
       this->on_z_wave_proxy_request(msg);
       break;
     }
+#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+    case HomeassistantActionResponse::MESSAGE_TYPE: {
+      HomeassistantActionResponse msg;
+      msg.decode(msg_data, msg_size);
+#ifdef HAS_PROTO_MESSAGE_DUMP
+      ESP_LOGVV(TAG, "on_homeassistant_action_response: %s", msg.dump().c_str());
+#endif
+      this->on_homeassistant_action_response(msg);
+      break;
+    }
 #endif
     default:
       break;

esphome/components/api/api_pb2_service.h

@@ -66,6 +66,9 @@ class APIServerConnectionBase : public ProtoService {
   virtual void on_subscribe_homeassistant_services_request(const SubscribeHomeassistantServicesRequest &value){};
 #endif
 
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  virtual void on_homeassistant_action_response(const HomeassistantActionResponse &value){};
+#endif
 #ifdef USE_API_HOMEASSISTANT_STATES
   virtual void on_subscribe_home_assistant_states_request(const SubscribeHomeAssistantStatesRequest &value){};
 #endif

esphome/components/api/api_server.cpp

@@ -5,16 +5,21 @@
 #include "esphome/components/network/util.h"
 #include "esphome/core/application.h"
 #include "esphome/core/defines.h"
+#include "esphome/core/controller_registry.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/log.h"
 #include "esphome/core/util.h"
 #include "esphome/core/version.h"
+#ifdef USE_API_HOMEASSISTANT_SERVICES
+#include "homeassistant_service.h"
+#endif
 
 #ifdef USE_LOGGER
 #include "esphome/components/logger/logger.h"
 #endif
 
 #include <algorithm>
+#include <utility>
 
 namespace esphome::api {
 
@@ -30,7 +35,7 @@ APIServer::APIServer() {
 }
 
 void APIServer::setup() {
-  this->setup_controller();
+  ControllerRegistry::register_controller(this);
 
 #ifdef USE_API_NOISE
   uint32_t hash = 88491486UL;
@@ -220,7 +225,7 @@ void APIServer::dump_config() {
                 "  Address: %s:%u\n"
                 "  Listen backlog: %u\n"
                 "  Max connections: %u",
-                network::get_use_address().c_str(), this->port_, this->listen_backlog_, this->max_connections_);
+                network::get_use_address(), this->port_, this->listen_backlog_, this->max_connections_);
 #ifdef USE_API_NOISE
   ESP_LOGCONFIG(TAG, "  Noise encryption: %s", YESNO(this->noise_ctx_->has_psk()));
   if (!this->noise_ctx_->has_psk()) {
@@ -265,7 +270,7 @@ bool APIServer::check_password(const uint8_t *password_data, size_t password_len
 
 void APIServer::handle_disconnect(APIConnection *conn) {}
 
-// Macro for entities without extra parameters
+// Macro for controller update dispatch
 #define API_DISPATCH_UPDATE(entity_type, entity_name) \
   void APIServer::on_##entity_name##_update(entity_type *obj) { /* NOLINT(bugprone-macro-parentheses) */ \
     if (obj->is_internal()) \
@@ -274,15 +279,6 @@ void APIServer::handle_disconnect(APIConnection *conn) {}
       c->send_##entity_name##_state(obj); \
   }
 
-// Macro for entities with extra parameters (but parameters not used in send)
-#define API_DISPATCH_UPDATE_IGNORE_PARAMS(entity_type, entity_name, ...) \
-  void APIServer::on_##entity_name##_update(entity_type *obj, __VA_ARGS__) { /* NOLINT(bugprone-macro-parentheses) */ \
-    if (obj->is_internal()) \
-      return; \
-    for (auto &c : this->clients_) \
-      c->send_##entity_name##_state(obj); \
-  }
-
 #ifdef USE_BINARY_SENSOR
 API_DISPATCH_UPDATE(binary_sensor::BinarySensor, binary_sensor)
 #endif
@@ -300,15 +296,15 @@ API_DISPATCH_UPDATE(light::LightState, light)
 #endif
 
 #ifdef USE_SENSOR
-API_DISPATCH_UPDATE_IGNORE_PARAMS(sensor::Sensor, sensor, float state)
+API_DISPATCH_UPDATE(sensor::Sensor, sensor)
 #endif
 
 #ifdef USE_SWITCH
-API_DISPATCH_UPDATE_IGNORE_PARAMS(switch_::Switch, switch, bool state)
+API_DISPATCH_UPDATE(switch_::Switch, switch)
 #endif
 
 #ifdef USE_TEXT_SENSOR
-API_DISPATCH_UPDATE_IGNORE_PARAMS(text_sensor::TextSensor, text_sensor, const std::string &state)
+API_DISPATCH_UPDATE(text_sensor::TextSensor, text_sensor)
 #endif
 
 #ifdef USE_CLIMATE
@@ -316,7 +312,7 @@ API_DISPATCH_UPDATE(climate::Climate, climate)
 #endif
 
 #ifdef USE_NUMBER
-API_DISPATCH_UPDATE_IGNORE_PARAMS(number::Number, number, float state)
+API_DISPATCH_UPDATE(number::Number, number)
 #endif
 
 #ifdef USE_DATETIME_DATE
@@ -332,11 +328,11 @@ API_DISPATCH_UPDATE(datetime::DateTimeEntity, datetime)
 #endif
 
 #ifdef USE_TEXT
-API_DISPATCH_UPDATE_IGNORE_PARAMS(text::Text, text, const std::string &state)
+API_DISPATCH_UPDATE(text::Text, text)
 #endif
 
 #ifdef USE_SELECT
-API_DISPATCH_UPDATE_IGNORE_PARAMS(select::Select, select, const std::string &state, size_t index)
+API_DISPATCH_UPDATE(select::Select, select)
 #endif
 
 #ifdef USE_LOCK
@@ -352,12 +348,13 @@ API_DISPATCH_UPDATE(media_player::MediaPlayer, media_player)
 #endif
 
 #ifdef USE_EVENT
-// Event is a special case - it's the only entity that passes extra parameters to the send method
-void APIServer::on_event(event::Event *obj, const std::string &event_type) {
+// Event is a special case - unlike other entities with simple state fields,
+// events store their state in a member accessed via obj->get_last_event_type()
+void APIServer::on_event(event::Event *obj) {
   if (obj->is_internal())
     return;
   for (auto &c : this->clients_)
-    c->send_event(obj, event_type);
+    c->send_event(obj, obj->get_last_event_type());
 }
 #endif
 
@@ -400,7 +397,38 @@ void APIServer::send_homeassistant_action(const HomeassistantActionRequest &call
     client->send_homeassistant_action(call);
   }
 }
-#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+void APIServer::register_action_response_callback(uint32_t call_id, ActionResponseCallback callback) {
+  this->action_response_callbacks_.push_back({call_id, std::move(callback)});
+}
+
+void APIServer::handle_action_response(uint32_t call_id, bool success, const std::string &error_message) {
+  for (auto it = this->action_response_callbacks_.begin(); it != this->action_response_callbacks_.end(); ++it) {
+    if (it->call_id == call_id) {
+      auto callback = std::move(it->callback);
+      this->action_response_callbacks_.erase(it);
+      ActionResponse response(success, error_message);
+      callback(response);
+      return;
+    }
+  }
+}
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+void APIServer::handle_action_response(uint32_t call_id, bool success, const std::string &error_message,
+                                       const uint8_t *response_data, size_t response_data_len) {
+  for (auto it = this->action_response_callbacks_.begin(); it != this->action_response_callbacks_.end(); ++it) {
+    if (it->call_id == call_id) {
+      auto callback = std::move(it->callback);
+      this->action_response_callbacks_.erase(it);
+      ActionResponse response(success, error_message, response_data, response_data_len);
+      callback(response);
+      return;
+    }
+  }
+}
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
+#endif  // USE_API_HOMEASSISTANT_SERVICES
 
 #ifdef USE_API_HOMEASSISTANT_STATES
 void APIServer::subscribe_home_assistant_state(std::string entity_id, optional<std::string> attribute,
@@ -433,6 +461,31 @@ uint16_t APIServer::get_port() const { return this->port_; }
 void APIServer::set_reboot_timeout(uint32_t reboot_timeout) { this->reboot_timeout_ = reboot_timeout; }
 
 #ifdef USE_API_NOISE
+bool APIServer::update_noise_psk_(const SavedNoisePsk &new_psk, const LogString *save_log_msg,
+                                  const LogString *fail_log_msg, const psk_t &active_psk, bool make_active) {
+  if (!this->noise_pref_.save(&new_psk)) {
+    ESP_LOGW(TAG, "%s", LOG_STR_ARG(fail_log_msg));
+    return false;
+  }
+  // ensure it's written immediately
+  if (!global_preferences->sync()) {
+    ESP_LOGW(TAG, "Failed to sync preferences");
+    return false;
+  }
+  ESP_LOGD(TAG, "%s", LOG_STR_ARG(save_log_msg));
+  if (make_active) {
+    this->set_timeout(100, [this, active_psk]() {
+      ESP_LOGW(TAG, "Disconnecting all clients to reset PSK");
+      this->set_noise_psk(active_psk);
+      for (auto &c : this->clients_) {
+        DisconnectRequest req;
+        c->send_message(req, DisconnectRequest::MESSAGE_TYPE);
+      }
+    });
+  }
+  return true;
+}
+
 bool APIServer::save_noise_psk(psk_t psk, bool make_active) {
 #ifdef USE_API_NOISE_PSK_FROM_YAML
   // When PSK is set from YAML, this function should never be called
@@ -447,27 +500,21 @@ bool APIServer::save_noise_psk(psk_t psk, bool make_active) {
   }
 
   SavedNoisePsk new_saved_psk{psk};
-  if (!this->noise_pref_.save(&new_saved_psk)) {
-    ESP_LOGW(TAG, "Failed to save Noise PSK");
-    return false;
-  }
-  // ensure it's written immediately
-  if (!global_preferences->sync()) {
-    ESP_LOGW(TAG, "Failed to sync preferences");
-    return false;
-  }
-  ESP_LOGD(TAG, "Noise PSK saved");
-  if (make_active) {
-    this->set_timeout(100, [this, psk]() {
-      ESP_LOGW(TAG, "Disconnecting all clients to reset PSK");
-      this->set_noise_psk(psk);
-      for (auto &c : this->clients_) {
-        DisconnectRequest req;
-        c->send_message(req, DisconnectRequest::MESSAGE_TYPE);
-      }
-    });
-  }
-  return true;
+  return this->update_noise_psk_(new_saved_psk, LOG_STR("Noise PSK saved"), LOG_STR("Failed to save Noise PSK"), psk,
+                                 make_active);
+#endif
+}
+bool APIServer::clear_noise_psk(bool make_active) {
+#ifdef USE_API_NOISE_PSK_FROM_YAML
+  // When PSK is set from YAML, this function should never be called
+  // but if it is, reject the change
+  ESP_LOGW(TAG, "Key set in YAML");
+  return false;
+#else
+  SavedNoisePsk empty_psk{};
+  psk_t empty{};
+  return this->update_noise_psk_(empty_psk, LOG_STR("Noise PSK cleared"), LOG_STR("Failed to clear Noise PSK"), empty,
+                                 make_active);
 #endif
 }
 #endif

esphome/components/api/api_server.h

@@ -16,6 +16,7 @@
 #include "user_services.h"
 #endif
 
+#include <map>
 #include <vector>
 
 namespace esphome::api {
@@ -52,6 +53,7 @@ class APIServer : public Component, public Controller {
 
 #ifdef USE_API_NOISE
   bool save_noise_psk(psk_t psk, bool make_active = true);
+  bool clear_noise_psk(bool make_active = true);
   void set_noise_psk(psk_t psk) { noise_ctx_->set_psk(psk); }
   std::shared_ptr<APINoiseContext> get_noise_ctx() { return noise_ctx_; }
 #endif  // USE_API_NOISE
@@ -70,19 +72,19 @@ class APIServer : public Component, public Controller {
   void on_light_update(light::LightState *obj) override;
 #endif
 #ifdef USE_SENSOR
-  void on_sensor_update(sensor::Sensor *obj, float state) override;
+  void on_sensor_update(sensor::Sensor *obj) override;
 #endif
 #ifdef USE_SWITCH
-  void on_switch_update(switch_::Switch *obj, bool state) override;
+  void on_switch_update(switch_::Switch *obj) override;
 #endif
 #ifdef USE_TEXT_SENSOR
-  void on_text_sensor_update(text_sensor::TextSensor *obj, const std::string &state) override;
+  void on_text_sensor_update(text_sensor::TextSensor *obj) override;
 #endif
 #ifdef USE_CLIMATE
   void on_climate_update(climate::Climate *obj) override;
 #endif
 #ifdef USE_NUMBER
-  void on_number_update(number::Number *obj, float state) override;
+  void on_number_update(number::Number *obj) override;
 #endif
 #ifdef USE_DATETIME_DATE
   void on_date_update(datetime::DateEntity *obj) override;
@@ -94,10 +96,10 @@ class APIServer : public Component, public Controller {
   void on_datetime_update(datetime::DateTimeEntity *obj) override;
 #endif
 #ifdef USE_TEXT
-  void on_text_update(text::Text *obj, const std::string &state) override;
+  void on_text_update(text::Text *obj) override;
 #endif
 #ifdef USE_SELECT
-  void on_select_update(select::Select *obj, const std::string &state, size_t index) override;
+  void on_select_update(select::Select *obj) override;
 #endif
 #ifdef USE_LOCK
   void on_lock_update(lock::Lock *obj) override;
@@ -111,10 +113,26 @@ class APIServer : public Component, public Controller {
 #ifdef USE_API_HOMEASSISTANT_SERVICES
   void send_homeassistant_action(const HomeassistantActionRequest &call);
 
-#endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  // Action response handling
+  using ActionResponseCallback = std::function<void(const class ActionResponse &)>;
+  void register_action_response_callback(uint32_t call_id, ActionResponseCallback callback);
+  void handle_action_response(uint32_t call_id, bool success, const std::string &error_message);
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  void handle_action_response(uint32_t call_id, bool success, const std::string &error_message,
+                              const uint8_t *response_data, size_t response_data_len);
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
+#endif  // USE_API_HOMEASSISTANT_SERVICES
 #ifdef USE_API_SERVICES
+  void initialize_user_services(std::initializer_list<UserServiceDescriptor *> services) {
+    this->user_services_.assign(services);
+  }
+#ifdef USE_API_CUSTOM_SERVICES
+  // Only compile push_back method when custom_services: true (external components)
   void register_user_service(UserServiceDescriptor *descriptor) { this->user_services_.push_back(descriptor); }
 #endif
+#endif
 #ifdef USE_HOMEASSISTANT_TIME
   void request_time();
 #endif
@@ -123,7 +141,7 @@ class APIServer : public Component, public Controller {
   void on_alarm_control_panel_update(alarm_control_panel::AlarmControlPanel *obj) override;
 #endif
 #ifdef USE_EVENT
-  void on_event(event::Event *obj, const std::string &event_type) override;
+  void on_event(event::Event *obj) override;
 #endif
 #ifdef USE_UPDATE
   void on_update(update::UpdateEntity *obj) override;
@@ -163,6 +181,10 @@ class APIServer : public Component, public Controller {
 
  protected:
   void schedule_reboot_timeout_();
+#ifdef USE_API_NOISE
+  bool update_noise_psk_(const SavedNoisePsk &new_psk, const LogString *save_log_msg, const LogString *fail_log_msg,
+                         const psk_t &active_psk, bool make_active);
+#endif  // USE_API_NOISE
   // Pointers and pointer-like types first (4 bytes each)
   std::unique_ptr<socket::Socket> socket_ = nullptr;
 #ifdef USE_API_CLIENT_CONNECTED_TRIGGER
@@ -187,6 +209,13 @@ class APIServer : public Component, public Controller {
 #ifdef USE_API_SERVICES
   std::vector<UserServiceDescriptor *> user_services_;
 #endif
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  struct PendingActionResponse {
+    uint32_t call_id;
+    ActionResponseCallback callback;
+  };
+  std::vector<PendingActionResponse> action_response_callbacks_;
+#endif
 
   // Group smaller types together
   uint16_t port_{6053};
@@ -208,7 +237,7 @@ extern APIServer *global_api_server;  // NOLINT(cppcoreguidelines-avoid-non-cons
 
 template<typename... Ts> class APIConnectedCondition : public Condition<Ts...> {
  public:
-  bool check(Ts... x) override { return global_api_server->is_connected(); }
+  bool check(const Ts &...x) override { return global_api_server->is_connected(); }
 };
 
 }  // namespace esphome::api

esphome/components/api/custom_api_device.h

@@ -9,11 +9,11 @@
 namespace esphome::api {
 
 #ifdef USE_API_SERVICES
-template<typename T, typename... Ts> class CustomAPIDeviceService : public UserServiceBase<Ts...> {
+template<typename T, typename... Ts> class CustomAPIDeviceService : public UserServiceDynamic<Ts...> {
  public:
   CustomAPIDeviceService(const std::string &name, const std::array<std::string, sizeof...(Ts)> &arg_names, T *obj,
                          void (T::*callback)(Ts...))
-      : UserServiceBase<Ts...>(name, arg_names), obj_(obj), callback_(callback) {}
+      : UserServiceDynamic<Ts...>(name, arg_names), obj_(obj), callback_(callback) {}
 
  protected:
   void execute(Ts... x) override { (this->obj_->*this->callback_)(x...); }  // NOLINT
@@ -53,8 +53,14 @@ class CustomAPIDevice {
   template<typename T, typename... Ts>
   void register_service(void (T::*callback)(Ts...), const std::string &name,
                         const std::array<std::string, sizeof...(Ts)> &arg_names) {
+#ifdef USE_API_CUSTOM_SERVICES
     auto *service = new CustomAPIDeviceService<T, Ts...>(name, arg_names, (T *) this, callback);  // NOLINT
     global_api_server->register_user_service(service);
+#else
+    static_assert(
+        sizeof(T) == 0,
+        "register_service() requires 'custom_services: true' in the 'api:' section of your YAML configuration");
+#endif
   }
 #else
   template<typename T, typename... Ts>
@@ -86,8 +92,14 @@ class CustomAPIDevice {
    */
 #ifdef USE_API_SERVICES
   template<typename T> void register_service(void (T::*callback)(), const std::string &name) {
+#ifdef USE_API_CUSTOM_SERVICES
     auto *service = new CustomAPIDeviceService<T>(name, {}, (T *) this, callback);  // NOLINT
     global_api_server->register_user_service(service);
+#else
+    static_assert(
+        sizeof(T) == 0,
+        "register_service() requires 'custom_services: true' in the 'api:' section of your YAML configuration");
+#endif
   }
 #else
   template<typename T> void register_service(void (T::*callback)(), const std::string &name) {
@@ -201,9 +213,9 @@ class CustomAPIDevice {
   void call_homeassistant_service(const std::string &service_name, const std::map<std::string, std::string> &data) {
     HomeassistantActionRequest resp;
     resp.set_service(StringRef(service_name));
+    resp.data.init(data.size());
     for (auto &it : data) {
-      resp.data.emplace_back();
-      auto &kv = resp.data.back();
+      auto &kv = resp.data.emplace_back();
       kv.set_key(StringRef(it.first));
       kv.value = it.second;
     }
@@ -244,9 +256,9 @@ class CustomAPIDevice {
     HomeassistantActionRequest resp;
     resp.set_service(StringRef(service_name));
     resp.is_event = true;
+    resp.data.init(data.size());
     for (auto &it : data) {
-      resp.data.emplace_back();
-      auto &kv = resp.data.back();
+      auto &kv = resp.data.emplace_back();
       kv.set_key(StringRef(it.first));
       kv.value = it.second;
     }

esphome/components/api/homeassistant_service.h

@@ -3,8 +3,13 @@
 #include "api_server.h"
 #ifdef USE_API
 #ifdef USE_API_HOMEASSISTANT_SERVICES
+#include <functional>
+#include <utility>
 #include <vector>
 #include "api_pb2.h"
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+#include "esphome/components/json/json_util.h"
+#endif
 #include "esphome/core/automation.h"
 #include "esphome/core/helpers.h"
 
@@ -36,66 +41,191 @@ template<typename... X> class TemplatableStringValue : public TemplatableValue<s
 
 template<typename... Ts> class TemplatableKeyValuePair {
  public:
+  // Default constructor needed for FixedVector::emplace_back()
+  TemplatableKeyValuePair() = default;
+
   // Keys are always string literals from YAML dictionary keys (e.g., "code", "event")
   // and never templatable values or lambdas. Only the value parameter can be a lambda/template.
   // Using pass-by-value with std::move allows optimal performance for both lvalues and rvalues.
   template<typename T> TemplatableKeyValuePair(std::string key, T value) : key(std::move(key)), value(value) {}
+
   std::string key;
   TemplatableStringValue<Ts...> value;
 };
 
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+// Represents the response data from a Home Assistant action
+class ActionResponse {
+ public:
+  ActionResponse(bool success, std::string error_message = "")
+      : success_(success), error_message_(std::move(error_message)) {}
+
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  ActionResponse(bool success, std::string error_message, const uint8_t *data, size_t data_len)
+      : success_(success), error_message_(std::move(error_message)) {
+    if (data == nullptr || data_len == 0)
+      return;
+    this->json_document_ = json::parse_json(data, data_len);
+  }
+#endif
+
+  bool is_success() const { return this->success_; }
+  const std::string &get_error_message() const { return this->error_message_; }
+
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  // Get data as parsed JSON object (const version returns read-only view)
+  JsonObjectConst get_json() const { return this->json_document_.as<JsonObjectConst>(); }
+#endif
+
+ protected:
+  bool success_;
+  std::string error_message_;
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  JsonDocument json_document_;
+#endif
+};
+
+// Callback type for action responses
+template<typename... Ts> using ActionResponseCallback = std::function<void(const ActionResponse &, Ts...)>;
+#endif
+
 template<typename... Ts> class HomeAssistantServiceCallAction : public Action<Ts...> {
  public:
-  explicit HomeAssistantServiceCallAction(APIServer *parent, bool is_event) : parent_(parent), is_event_(is_event) {}
+  explicit HomeAssistantServiceCallAction(APIServer *parent, bool is_event) : parent_(parent) {
+    this->flags_.is_event = is_event;
+  }
 
   template<typename T> void set_service(T service) { this->service_ = service; }
 
+  // Initialize FixedVector members - called from Python codegen with compile-time known sizes.
+  // Must be called before any add_* methods; capacity must match the number of subsequent add_* calls.
+  void init_data(size_t count) { this->data_.init(count); }
+  void init_data_template(size_t count) { this->data_template_.init(count); }
+  void init_variables(size_t count) { this->variables_.init(count); }
+
   // Keys are always string literals from the Python code generation (e.g., cg.add(var.add_data("tag_id", templ))).
   // The value parameter can be a lambda/template, but keys are never templatable.
-  // Using pass-by-value allows the compiler to optimize for both lvalues and rvalues.
-  template<typename T> void add_data(std::string key, T value) { this->data_.emplace_back(std::move(key), value); }
-  template<typename T> void add_data_template(std::string key, T value) {
-    this->data_template_.emplace_back(std::move(key), value);
+  template<typename K, typename V> void add_data(K &&key, V &&value) {
+    this->add_kv_(this->data_, std::forward<K>(key), std::forward<V>(value));
   }
-  template<typename T> void add_variable(std::string key, T value) {
-    this->variables_.emplace_back(std::move(key), value);
+  template<typename K, typename V> void add_data_template(K &&key, V &&value) {
+    this->add_kv_(this->data_template_, std::forward<K>(key), std::forward<V>(value));
+  }
+  template<typename K, typename V> void add_variable(K &&key, V &&value) {
+    this->add_kv_(this->variables_, std::forward<K>(key), std::forward<V>(value));
   }
 
-  void play(Ts... x) override {
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+  template<typename T> void set_response_template(T response_template) {
+    this->response_template_ = response_template;
+    this->flags_.has_response_template = true;
+  }
+
+  void set_wants_status() { this->flags_.wants_status = true; }
+  void set_wants_response() { this->flags_.wants_response = true; }
+
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  Trigger<JsonObjectConst, Ts...> *get_success_trigger_with_response() const {
+    return this->success_trigger_with_response_;
+  }
+#endif
+  Trigger<Ts...> *get_success_trigger() const { return this->success_trigger_; }
+  Trigger<std::string, Ts...> *get_error_trigger() const { return this->error_trigger_; }
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
+
+  void play(const Ts &...x) override {
     HomeassistantActionRequest resp;
     std::string service_value = this->service_.value(x...);
     resp.set_service(StringRef(service_value));
-    resp.is_event = this->is_event_;
-    for (auto &it : this->data_) {
-      resp.data.emplace_back();
-      auto &kv = resp.data.back();
-      kv.set_key(StringRef(it.key));
-      kv.value = it.value.value(x...);
-    }
-    for (auto &it : this->data_template_) {
-      resp.data_template.emplace_back();
-      auto &kv = resp.data_template.back();
-      kv.set_key(StringRef(it.key));
-      kv.value = it.value.value(x...);
-    }
-    for (auto &it : this->variables_) {
-      resp.variables.emplace_back();
-      auto &kv = resp.variables.back();
-      kv.set_key(StringRef(it.key));
-      kv.value = it.value.value(x...);
+    resp.is_event = this->flags_.is_event;
+    this->populate_service_map(resp.data, this->data_, x...);
+    this->populate_service_map(resp.data_template, this->data_template_, x...);
+    this->populate_service_map(resp.variables, this->variables_, x...);
+
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+    if (this->flags_.wants_status) {
+      // Generate a unique call ID for this service call
+      static uint32_t call_id_counter = 1;
+      uint32_t call_id = call_id_counter++;
+      resp.call_id = call_id;
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+      if (this->flags_.wants_response) {
+        resp.wants_response = true;
+        // Set response template if provided
+        if (this->flags_.has_response_template) {
+          std::string response_template_value = this->response_template_.value(x...);
+          resp.response_template = response_template_value;
+        }
+      }
+#endif
+
+      auto captured_args = std::make_tuple(x...);
+      this->parent_->register_action_response_callback(call_id, [this, captured_args](const ActionResponse &response) {
+        std::apply(
+            [this, &response](auto &&...args) {
+              if (response.is_success()) {
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+                if (this->flags_.wants_response) {
+                  this->success_trigger_with_response_->trigger(response.get_json(), args...);
+                } else
+#endif
+                {
+                  this->success_trigger_->trigger(args...);
+                }
+              } else {
+                this->error_trigger_->trigger(response.get_error_message(), args...);
+              }
+            },
+            captured_args);
+      });
     }
+#endif
+
     this->parent_->send_homeassistant_action(resp);
   }
 
  protected:
+  // Helper to add key-value pairs to FixedVectors with perfect forwarding to avoid copies
+  template<typename K, typename V> void add_kv_(FixedVector<TemplatableKeyValuePair<Ts...>> &vec, K &&key, V &&value) {
+    auto &kv = vec.emplace_back();
+    kv.key = std::forward<K>(key);
+    kv.value = std::forward<V>(value);
+  }
+
+  template<typename VectorType, typename SourceType>
+  static void populate_service_map(VectorType &dest, SourceType &source, Ts... x) {
+    dest.init(source.size());
+    for (auto &it : source) {
+      auto &kv = dest.emplace_back();
+      kv.set_key(StringRef(it.key));
+      kv.value = it.value.value(x...);
+    }
+  }
+
   APIServer *parent_;
-  bool is_event_;
   TemplatableStringValue<Ts...> service_{};
-  std::vector<TemplatableKeyValuePair<Ts...>> data_;
-  std::vector<TemplatableKeyValuePair<Ts...>> data_template_;
-  std::vector<TemplatableKeyValuePair<Ts...>> variables_;
+  FixedVector<TemplatableKeyValuePair<Ts...>> data_;
+  FixedVector<TemplatableKeyValuePair<Ts...>> data_template_;
+  FixedVector<TemplatableKeyValuePair<Ts...>> variables_;
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
+#ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  TemplatableStringValue<Ts...> response_template_{""};
+  Trigger<JsonObjectConst, Ts...> *success_trigger_with_response_ = new Trigger<JsonObjectConst, Ts...>();
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
+  Trigger<Ts...> *success_trigger_ = new Trigger<Ts...>();
+  Trigger<std::string, Ts...> *error_trigger_ = new Trigger<std::string, Ts...>();
+#endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
+
+  struct Flags {
+    uint8_t is_event : 1;
+    uint8_t wants_status : 1;
+    uint8_t wants_response : 1;
+    uint8_t has_response_template : 1;
+    uint8_t reserved : 5;
+  } flags_{0};
 };
 
 }  // namespace esphome::api
+
 #endif
 #endif

esphome/components/api/proto.cpp

@@ -7,6 +7,69 @@ namespace esphome::api {
 
 static const char *const TAG = "api.proto";
 
+uint32_t ProtoDecodableMessage::count_repeated_field(const uint8_t *buffer, size_t length, uint32_t target_field_id) {
+  uint32_t count = 0;
+  const uint8_t *ptr = buffer;
+  const uint8_t *end = buffer + length;
+
+  while (ptr < end) {
+    uint32_t consumed;
+
+    // Parse field header (tag)
+    auto res = ProtoVarInt::parse(ptr, end - ptr, &consumed);
+    if (!res.has_value()) {
+      break;  // Invalid data, stop counting
+    }
+
+    uint32_t tag = res->as_uint32();
+    uint32_t field_type = tag & WIRE_TYPE_MASK;
+    uint32_t field_id = tag >> 3;
+    ptr += consumed;
+
+    // Count if this is the target field
+    if (field_id == target_field_id) {
+      count++;
+    }
+
+    // Skip field data based on wire type
+    switch (field_type) {
+      case WIRE_TYPE_VARINT: {  // VarInt - parse and skip
+        res = ProtoVarInt::parse(ptr, end - ptr, &consumed);
+        if (!res.has_value()) {
+          return count;  // Invalid data, return what we have
+        }
+        ptr += consumed;
+        break;
+      }
+      case WIRE_TYPE_LENGTH_DELIMITED: {  // Length-delimited - parse length and skip data
+        res = ProtoVarInt::parse(ptr, end - ptr, &consumed);
+        if (!res.has_value()) {
+          return count;
+        }
+        uint32_t field_length = res->as_uint32();
+        ptr += consumed;
+        if (ptr + field_length > end) {
+          return count;  // Out of bounds
+        }
+        ptr += field_length;
+        break;
+      }
+      case WIRE_TYPE_FIXED32: {  // 32-bit - skip 4 bytes
+        if (ptr + 4 > end) {
+          return count;
+        }
+        ptr += 4;
+        break;
+      }
+      default:
+        // Unknown wire type, can't continue
+        return count;
+    }
+  }
+
+  return count;
+}
+
 void ProtoDecodableMessage::decode(const uint8_t *buffer, size_t length) {
   const uint8_t *ptr = buffer;
   const uint8_t *end = buffer + length;
@@ -22,12 +85,12 @@ void ProtoDecodableMessage::decode(const uint8_t *buffer, size_t length) {
     }
 
     uint32_t tag = res->as_uint32();
-    uint32_t field_type = tag & 0b111;
+    uint32_t field_type = tag & WIRE_TYPE_MASK;
     uint32_t field_id = tag >> 3;
     ptr += consumed;
 
     switch (field_type) {
-      case 0: {  // VarInt
+      case WIRE_TYPE_VARINT: {  // VarInt
         res = ProtoVarInt::parse(ptr, end - ptr, &consumed);
         if (!res.has_value()) {
           ESP_LOGV(TAG, "Invalid VarInt at offset %ld", (long) (ptr - buffer));
@@ -39,7 +102,7 @@ void ProtoDecodableMessage::decode(const uint8_t *buffer, size_t length) {
         ptr += consumed;
         break;
       }
-      case 2: {  // Length-delimited
+      case WIRE_TYPE_LENGTH_DELIMITED: {  // Length-delimited
         res = ProtoVarInt::parse(ptr, end - ptr, &consumed);
         if (!res.has_value()) {
           ESP_LOGV(TAG, "Invalid Length Delimited at offset %ld", (long) (ptr - buffer));
@@ -57,7 +120,7 @@ void ProtoDecodableMessage::decode(const uint8_t *buffer, size_t length) {
         ptr += field_length;
         break;
       }
-      case 5: {  // 32-bit
+      case WIRE_TYPE_FIXED32: {  // 32-bit
         if (ptr + 4 > end) {
           ESP_LOGV(TAG, "Out-of-bounds Fixed32-bit at offset %ld", (long) (ptr - buffer));
           return;

esphome/components/api/proto.h

@@ -15,6 +15,13 @@
 
 namespace esphome::api {
 
+// Protocol Buffer wire type constants
+// See https://protobuf.dev/programming-guides/encoding/#structure
+constexpr uint8_t WIRE_TYPE_VARINT = 0;            // int32, int64, uint32, uint64, sint32, sint64, bool, enum
+constexpr uint8_t WIRE_TYPE_LENGTH_DELIMITED = 2;  // string, bytes, embedded messages, packed repeated fields
+constexpr uint8_t WIRE_TYPE_FIXED32 = 5;           // fixed32, sfixed32, float
+constexpr uint8_t WIRE_TYPE_MASK = 0b111;          // Mask to extract wire type from tag
+
 // Helper functions for ZigZag encoding/decoding
 inline constexpr uint32_t encode_zigzag32(int32_t value) {
   return (static_cast<uint32_t>(value) << 1) ^ (static_cast<uint32_t>(value >> 31));
@@ -241,7 +248,7 @@ class ProtoWriteBuffer {
    * Following https://protobuf.dev/programming-guides/encoding/#structure
    */
   void encode_field_raw(uint32_t field_id, uint32_t type) {
-    uint32_t val = (field_id << 3) | (type & 0b111);
+    uint32_t val = (field_id << 3) | (type & WIRE_TYPE_MASK);
     this->encode_varint_raw(val);
   }
   void encode_string(uint32_t field_id, const char *string, size_t len, bool force = false) {
@@ -354,7 +361,18 @@ class ProtoMessage {
 // Base class for messages that support decoding
 class ProtoDecodableMessage : public ProtoMessage {
  public:
-  void decode(const uint8_t *buffer, size_t length);
+  virtual void decode(const uint8_t *buffer, size_t length);
+
+  /**
+   * Count occurrences of a repeated field in a protobuf buffer.
+   * This is a lightweight scan that only parses tags and skips field data.
+   *
+   * @param buffer Pointer to the protobuf buffer
+   * @param length Length of the buffer in bytes
+   * @param target_field_id The field ID to count
+   * @return Number of times the field appears in the buffer
+   */
+  static uint32_t count_repeated_field(const uint8_t *buffer, size_t length, uint32_t target_field_id);
 
  protected:
   virtual bool decode_varint(uint32_t field_id, ProtoVarInt value) { return false; }
@@ -482,7 +500,7 @@ class ProtoSize {
    * @return The number of bytes needed to encode the field ID and wire type
    */
   static constexpr uint32_t field(uint32_t field_id, uint32_t type) {
-    uint32_t tag = (field_id << 3) | (type & 0b111);
+    uint32_t tag = (field_id << 3) | (type & WIRE_TYPE_MASK);
     return varint(tag);
   }
 
@@ -749,13 +767,29 @@ class ProtoSize {
   template<typename MessageType>
   inline void add_repeated_message(uint32_t field_id_size, const std::vector<MessageType> &messages) {
     // Skip if the vector is empty
-    if (messages.empty()) {
-      return;
+    if (!messages.empty()) {
+      // Use the force version for all messages in the repeated field
+      for (const auto &message : messages) {
+        add_message_object_force(field_id_size, message);
+      }
     }
+  }
 
-    // Use the force version for all messages in the repeated field
-    for (const auto &message : messages) {
-      add_message_object_force(field_id_size, message);
+  /**
+   * @brief Calculates and adds the sizes of all messages in a repeated field to the total message size (FixedVector
+   * version)
+   *
+   * @tparam MessageType The type of the nested messages in the FixedVector
+   * @param messages FixedVector of message objects
+   */
+  template<typename MessageType>
+  inline void add_repeated_message(uint32_t field_id_size, const FixedVector<MessageType> &messages) {
+    // Skip if the fixed vector is empty
+    if (!messages.empty()) {
+      // Use the force version for all messages in the repeated field
+      for (const auto &message : messages) {
+        add_message_object_force(field_id_size, message);
+      }
     }
   }
 };

esphome/components/api/user_services.cpp

@@ -11,16 +11,49 @@ template<> int32_t get_execute_arg_value<int32_t>(const ExecuteServiceArgument &
 }
 template<> float get_execute_arg_value<float>(const ExecuteServiceArgument &arg) { return arg.float_; }
 template<> std::string get_execute_arg_value<std::string>(const ExecuteServiceArgument &arg) { return arg.string_; }
+
+// Legacy std::vector versions for external components using custom_api_device.h - optimized with reserve
 template<> std::vector<bool> get_execute_arg_value<std::vector<bool>>(const ExecuteServiceArgument &arg) {
-  return arg.bool_array;
+  std::vector<bool> result;
+  result.reserve(arg.bool_array.size());
+  result.insert(result.end(), arg.bool_array.begin(), arg.bool_array.end());
+  return result;
 }
 template<> std::vector<int32_t> get_execute_arg_value<std::vector<int32_t>>(const ExecuteServiceArgument &arg) {
-  return arg.int_array;
+  std::vector<int32_t> result;
+  result.reserve(arg.int_array.size());
+  result.insert(result.end(), arg.int_array.begin(), arg.int_array.end());
+  return result;
 }
 template<> std::vector<float> get_execute_arg_value<std::vector<float>>(const ExecuteServiceArgument &arg) {
-  return arg.float_array;
+  std::vector<float> result;
+  result.reserve(arg.float_array.size());
+  result.insert(result.end(), arg.float_array.begin(), arg.float_array.end());
+  return result;
 }
 template<> std::vector<std::string> get_execute_arg_value<std::vector<std::string>>(const ExecuteServiceArgument &arg) {
+  std::vector<std::string> result;
+  result.reserve(arg.string_array.size());
+  result.insert(result.end(), arg.string_array.begin(), arg.string_array.end());
+  return result;
+}
+
+// New FixedVector const reference versions for YAML-generated services - zero-copy
+template<>
+const FixedVector<bool> &get_execute_arg_value<const FixedVector<bool> &>(const ExecuteServiceArgument &arg) {
+  return arg.bool_array;
+}
+template<>
+const FixedVector<int32_t> &get_execute_arg_value<const FixedVector<int32_t> &>(const ExecuteServiceArgument &arg) {
+  return arg.int_array;
+}
+template<>
+const FixedVector<float> &get_execute_arg_value<const FixedVector<float> &>(const ExecuteServiceArgument &arg) {
+  return arg.float_array;
+}
+template<>
+const FixedVector<std::string> &get_execute_arg_value<const FixedVector<std::string> &>(
+    const ExecuteServiceArgument &arg) {
   return arg.string_array;
 }
 
@@ -28,6 +61,8 @@ template<> enums::ServiceArgType to_service_arg_type<bool>() { return enums::SER
 template<> enums::ServiceArgType to_service_arg_type<int32_t>() { return enums::SERVICE_ARG_TYPE_INT; }
 template<> enums::ServiceArgType to_service_arg_type<float>() { return enums::SERVICE_ARG_TYPE_FLOAT; }
 template<> enums::ServiceArgType to_service_arg_type<std::string>() { return enums::SERVICE_ARG_TYPE_STRING; }
+
+// Legacy std::vector versions for external components using custom_api_device.h
 template<> enums::ServiceArgType to_service_arg_type<std::vector<bool>>() { return enums::SERVICE_ARG_TYPE_BOOL_ARRAY; }
 template<> enums::ServiceArgType to_service_arg_type<std::vector<int32_t>>() {
   return enums::SERVICE_ARG_TYPE_INT_ARRAY;
@@ -39,4 +74,18 @@ template<> enums::ServiceArgType to_service_arg_type<std::vector<std::string>>()
   return enums::SERVICE_ARG_TYPE_STRING_ARRAY;
 }
 
+// New FixedVector const reference versions for YAML-generated services
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<bool> &>() {
+  return enums::SERVICE_ARG_TYPE_BOOL_ARRAY;
+}
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<int32_t> &>() {
+  return enums::SERVICE_ARG_TYPE_INT_ARRAY;
+}
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<float> &>() {
+  return enums::SERVICE_ARG_TYPE_FLOAT_ARRAY;
+}
+template<> enums::ServiceArgType to_service_arg_type<const FixedVector<std::string> &>() {
+  return enums::SERVICE_ARG_TYPE_STRING_ARRAY;
+}
+
 }  // namespace esphome::api

esphome/components/api/user_services.h

@@ -23,11 +23,13 @@ template<typename T> T get_execute_arg_value(const ExecuteServiceArgument &arg);
 
 template<typename T> enums::ServiceArgType to_service_arg_type();
 
+// Base class for YAML-defined services (most common case)
+// Stores only pointers to string literals in flash - no heap allocation
 template<typename... Ts> class UserServiceBase : public UserServiceDescriptor {
  public:
-  UserServiceBase(std::string name, const std::array<std::string, sizeof...(Ts)> &arg_names)
-      : name_(std::move(name)), arg_names_(arg_names) {
-    this->key_ = fnv1_hash(this->name_);
+  UserServiceBase(const char *name, const std::array<const char *, sizeof...(Ts)> &arg_names)
+      : name_(name), arg_names_(arg_names) {
+    this->key_ = fnv1_hash(name);
   }
 
   ListEntitiesServicesResponse encode_list_service_response() override {
@@ -35,9 +37,9 @@ template<typename... Ts> class UserServiceBase : public UserServiceDescriptor {
     msg.set_name(StringRef(this->name_));
     msg.key = this->key_;
     std::array<enums::ServiceArgType, sizeof...(Ts)> arg_types = {to_service_arg_type<Ts>()...};
-    for (int i = 0; i < sizeof...(Ts); i++) {
-      msg.args.emplace_back();
-      auto &arg = msg.args.back();
+    msg.args.init(sizeof...(Ts));
+    for (size_t i = 0; i < sizeof...(Ts); i++) {
+      auto &arg = msg.args.emplace_back();
       arg.type = arg_types[i];
       arg.set_name(StringRef(this->arg_names_[i]));
     }
@@ -47,7 +49,7 @@ template<typename... Ts> class UserServiceBase : public UserServiceDescriptor {
   bool execute_service(const ExecuteServiceRequest &req) override {
     if (req.key != this->key_)
       return false;
-    if (req.args.size() != this->arg_names_.size())
+    if (req.args.size() != sizeof...(Ts))
       return false;
     this->execute_(req.args, typename gens<sizeof...(Ts)>::type());
     return true;
@@ -55,18 +57,64 @@ template<typename... Ts> class UserServiceBase : public UserServiceDescriptor {
 
  protected:
   virtual void execute(Ts... x) = 0;
-  template<int... S> void execute_(const std::vector<ExecuteServiceArgument> &args, seq<S...> type) {
+  template<typename ArgsContainer, int... S> void execute_(const ArgsContainer &args, seq<S...> type) {
     this->execute((get_execute_arg_value<Ts>(args[S]))...);
   }
 
-  std::string name_;
+  // Pointers to string literals in flash - no heap allocation
+  const char *name_;
+  std::array<const char *, sizeof...(Ts)> arg_names_;
   uint32_t key_{0};
+};
+
+// Separate class for custom_api_device services (rare case)
+// Stores copies of runtime-generated names
+template<typename... Ts> class UserServiceDynamic : public UserServiceDescriptor {
+ public:
+  UserServiceDynamic(std::string name, const std::array<std::string, sizeof...(Ts)> &arg_names)
+      : name_(std::move(name)), arg_names_(arg_names) {
+    this->key_ = fnv1_hash(this->name_.c_str());
+  }
+
+  ListEntitiesServicesResponse encode_list_service_response() override {
+    ListEntitiesServicesResponse msg;
+    msg.set_name(StringRef(this->name_));
+    msg.key = this->key_;
+    std::array<enums::ServiceArgType, sizeof...(Ts)> arg_types = {to_service_arg_type<Ts>()...};
+    msg.args.init(sizeof...(Ts));
+    for (size_t i = 0; i < sizeof...(Ts); i++) {
+      auto &arg = msg.args.emplace_back();
+      arg.type = arg_types[i];
+      arg.set_name(StringRef(this->arg_names_[i]));
+    }
+    return msg;
+  }
+
+  bool execute_service(const ExecuteServiceRequest &req) override {
+    if (req.key != this->key_)
+      return false;
+    if (req.args.size() != sizeof...(Ts))
+      return false;
+    this->execute_(req.args, typename gens<sizeof...(Ts)>::type());
+    return true;
+  }
+
+ protected:
+  virtual void execute(Ts... x) = 0;
+  template<typename ArgsContainer, int... S> void execute_(const ArgsContainer &args, seq<S...> type) {
+    this->execute((get_execute_arg_value<Ts>(args[S]))...);
+  }
+
+  // Heap-allocated strings for runtime-generated names
+  std::string name_;
   std::array<std::string, sizeof...(Ts)> arg_names_;
+  uint32_t key_{0};
 };
 
 template<typename... Ts> class UserServiceTrigger : public UserServiceBase<Ts...>, public Trigger<Ts...> {
  public:
-  UserServiceTrigger(const std::string &name, const std::array<std::string, sizeof...(Ts)> &arg_names)
+  // Constructor for static names (YAML-defined services - used by code generator)
+  UserServiceTrigger(const char *name, const std::array<const char *, sizeof...(Ts)> &arg_names)
       : UserServiceBase<Ts...>(name, arg_names) {}
 
  protected:

esphome/components/at581x/automation.h

@@ -10,7 +10,7 @@ namespace at581x {
 
 template<typename... Ts> class AT581XResetAction : public Action<Ts...>, public Parented<AT581XComponent> {
  public:
-  void play(Ts... x) { this->parent_->reset_hardware_frontend(); }
+  void play(const Ts &...x) { this->parent_->reset_hardware_frontend(); }
 };
 
 template<typename... Ts> class AT581XSettingsAction : public Action<Ts...>, public Parented<AT581XComponent> {
@@ -25,7 +25,7 @@ template<typename... Ts> class AT581XSettingsAction : public Action<Ts...>, publ
   TEMPLATABLE_VALUE(int, trigger_keep)
   TEMPLATABLE_VALUE(int, stage_gain)
 
-  void play(Ts... x) {
+  void play(const Ts &...x) {
     if (this->frequency_.has_value()) {
       int v = this->frequency_.value(x...);
       this->parent_->set_frequency(v);

esphome/components/audio/__init__.py

@@ -165,4 +165,4 @@ def final_validate_audio_schema(
 
 
 async def to_code(config):
-    cg.add_library("esphome/esp-audio-libs", "1.1.4")
+    cg.add_library("esphome/esp-audio-libs", "2.0.1")

esphome/components/audio/audio.cpp

@@ -57,7 +57,7 @@ const char *audio_file_type_to_string(AudioFileType file_type) {
 void scale_audio_samples(const int16_t *audio_samples, int16_t *output_buffer, int16_t scale_factor,
                          size_t samples_to_scale) {
   // Note the assembly dsps_mulc function has audio glitches if the input and output buffers are the same.
-  for (int i = 0; i < samples_to_scale; i++) {
+  for (size_t i = 0; i < samples_to_scale; i++) {
     int32_t acc = (int32_t) audio_samples[i] * (int32_t) scale_factor;
     output_buffer[i] = (int16_t) (acc >> 15);
   }

esphome/components/audio/audio_decoder.cpp

@@ -229,18 +229,18 @@ FileDecoderState AudioDecoder::decode_flac_() {
     auto result = this->flac_decoder_->read_header(this->input_transfer_buffer_->get_buffer_start(),
                                                    this->input_transfer_buffer_->available());
 
-    if (result == esp_audio_libs::flac::FLAC_DECODER_HEADER_OUT_OF_DATA) {
-      return FileDecoderState::POTENTIALLY_FAILED;
-    }
-
-    if (result != esp_audio_libs::flac::FLAC_DECODER_SUCCESS) {
-      // Couldn't read FLAC header
+    if (result > esp_audio_libs::flac::FLAC_DECODER_HEADER_OUT_OF_DATA) {
+      // Serrious error reading FLAC header, there is no recovery
       return FileDecoderState::FAILED;
     }
 
     size_t bytes_consumed = this->flac_decoder_->get_bytes_index();
     this->input_transfer_buffer_->decrease_buffer_length(bytes_consumed);
 
+    if (result == esp_audio_libs::flac::FLAC_DECODER_HEADER_OUT_OF_DATA) {
+      return FileDecoderState::MORE_TO_PROCESS;
+    }
+
     // Reallocate the output transfer buffer to the smallest necessary size
     this->free_buffer_required_ = flac_decoder_->get_output_buffer_size_bytes();
     if (!this->output_transfer_buffer_->reallocate(this->free_buffer_required_)) {
@@ -256,9 +256,9 @@ FileDecoderState AudioDecoder::decode_flac_() {
   }
 
   uint32_t output_samples = 0;
-  auto result = this->flac_decoder_->decode_frame(
-      this->input_transfer_buffer_->get_buffer_start(), this->input_transfer_buffer_->available(),
-      reinterpret_cast<int16_t *>(this->output_transfer_buffer_->get_buffer_end()), &output_samples);
+  auto result = this->flac_decoder_->decode_frame(this->input_transfer_buffer_->get_buffer_start(),
+                                                  this->input_transfer_buffer_->available(),
+                                                  this->output_transfer_buffer_->get_buffer_end(), &output_samples);
 
   if (result == esp_audio_libs::flac::FLAC_DECODER_ERROR_OUT_OF_DATA) {
     // Not an issue, just needs more data that we'll get next time.

esphome/components/audio_adc/automation.h

@@ -13,7 +13,7 @@ template<typename... Ts> class SetMicGainAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(float, mic_gain)
 
-  void play(Ts... x) override { this->audio_adc_->set_mic_gain(this->mic_gain_.value(x...)); }
+  void play(const Ts &...x) override { this->audio_adc_->set_mic_gain(this->mic_gain_.value(x...)); }
 
  protected:
   AudioAdc *audio_adc_;

esphome/components/audio_dac/automation.h

@@ -11,7 +11,7 @@ template<typename... Ts> class MuteOffAction : public Action<Ts...> {
  public:
   explicit MuteOffAction(AudioDac *audio_dac) : audio_dac_(audio_dac) {}
 
-  void play(Ts... x) override { this->audio_dac_->set_mute_off(); }
+  void play(const Ts &...x) override { this->audio_dac_->set_mute_off(); }
 
  protected:
   AudioDac *audio_dac_;
@@ -21,7 +21,7 @@ template<typename... Ts> class MuteOnAction : public Action<Ts...> {
  public:
   explicit MuteOnAction(AudioDac *audio_dac) : audio_dac_(audio_dac) {}
 
-  void play(Ts... x) override { this->audio_dac_->set_mute_on(); }
+  void play(const Ts &...x) override { this->audio_dac_->set_mute_on(); }
 
  protected:
   AudioDac *audio_dac_;
@@ -33,7 +33,7 @@ template<typename... Ts> class SetVolumeAction : public Action<Ts...> {
 
   TEMPLATABLE_VALUE(float, volume)
 
-  void play(Ts... x) override { this->audio_dac_->set_volume(this->volume_.value(x...)); }
+  void play(const Ts &...x) override { this->audio_dac_->set_volume(this->volume_.value(x...)); }
 
  protected:
   AudioDac *audio_dac_;

esphome/components/bang_bang/bang_bang_climate.cpp

@@ -6,6 +6,9 @@ namespace bang_bang {
 
 static const char *const TAG = "bang_bang.climate";
 
+BangBangClimate::BangBangClimate()
+    : idle_trigger_(new Trigger<>()), cool_trigger_(new Trigger<>()), heat_trigger_(new Trigger<>()) {}
+
 void BangBangClimate::setup() {
   this->sensor_->add_on_state_callback([this](float state) {
     this->current_temperature = state;
@@ -31,53 +34,63 @@ void BangBangClimate::setup() {
     restore->to_call(this).perform();
   } else {
     // restore from defaults, change_away handles those for us
-    if (supports_cool_ && supports_heat_) {
+    if (this->supports_cool_ && this->supports_heat_) {
       this->mode = climate::CLIMATE_MODE_HEAT_COOL;
-    } else if (supports_cool_) {
+    } else if (this->supports_cool_) {
       this->mode = climate::CLIMATE_MODE_COOL;
-    } else if (supports_heat_) {
+    } else if (this->supports_heat_) {
       this->mode = climate::CLIMATE_MODE_HEAT;
     }
     this->change_away_(false);
   }
 }
+
 void BangBangClimate::control(const climate::ClimateCall &call) {
-  if (call.get_mode().has_value())
+  if (call.get_mode().has_value()) {
     this->mode = *call.get_mode();
-  if (call.get_target_temperature_low().has_value())
+  }
+  if (call.get_target_temperature_low().has_value()) {
     this->target_temperature_low = *call.get_target_temperature_low();
-  if (call.get_target_temperature_high().has_value())
+  }
+  if (call.get_target_temperature_high().has_value()) {
     this->target_temperature_high = *call.get_target_temperature_high();
-  if (call.get_preset().has_value())
+  }
+  if (call.get_preset().has_value()) {
     this->change_away_(*call.get_preset() == climate::CLIMATE_PRESET_AWAY);
+  }
 
   this->compute_state_();
   this->publish_state();
 }
+
 climate::ClimateTraits BangBangClimate::traits() {
   auto traits = climate::ClimateTraits();
-  traits.set_supports_current_temperature(true);
-  if (this->humidity_sensor_ != nullptr)
-    traits.set_supports_current_humidity(true);
+  traits.add_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_TEMPERATURE |
+                           climate::CLIMATE_REQUIRES_TWO_POINT_TARGET_TEMPERATURE | climate::CLIMATE_SUPPORTS_ACTION);
+  if (this->humidity_sensor_ != nullptr) {
+    traits.add_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_HUMIDITY);
+  }
   traits.set_supported_modes({
       climate::CLIMATE_MODE_OFF,
   });
-  if (supports_cool_)
+  if (this->supports_cool_) {
     traits.add_supported_mode(climate::CLIMATE_MODE_COOL);
-  if (supports_heat_)
+  }
+  if (this->supports_heat_) {
     traits.add_supported_mode(climate::CLIMATE_MODE_HEAT);
-  if (supports_cool_ && supports_heat_)
+  }
+  if (this->supports_cool_ && this->supports_heat_) {
     traits.add_supported_mode(climate::CLIMATE_MODE_HEAT_COOL);
-  traits.set_supports_two_point_target_temperature(true);
-  if (supports_away_) {
+  }
+  if (this->supports_away_) {
     traits.set_supported_presets({
         climate::CLIMATE_PRESET_HOME,
         climate::CLIMATE_PRESET_AWAY,
     });
   }
-  traits.set_supports_action(true);
   return traits;
 }
+
 void BangBangClimate::compute_state_() {
   if (this->mode == climate::CLIMATE_MODE_OFF) {
     this->switch_to_action_(climate::CLIMATE_ACTION_OFF);
@@ -122,6 +135,7 @@ void BangBangClimate::compute_state_() {
 
   this->switch_to_action_(target_action);
 }
+
 void BangBangClimate::switch_to_action_(climate::ClimateAction action) {
   if (action == this->action) {
     // already in target mode
@@ -166,6 +180,7 @@ void BangBangClimate::switch_to_action_(climate::ClimateAction action) {
   this->prev_trigger_ = trig;
   this->publish_state();
 }
+
 void BangBangClimate::change_away_(bool away) {
   if (!away) {
     this->target_temperature_low = this->normal_config_.default_temperature_low;
@@ -176,22 +191,26 @@ void BangBangClimate::change_away_(bool away) {
   }
   this->preset = away ? climate::CLIMATE_PRESET_AWAY : climate::CLIMATE_PRESET_HOME;
 }
+
 void BangBangClimate::set_normal_config(const BangBangClimateTargetTempConfig &normal_config) {
   this->normal_config_ = normal_config;
 }
+
 void BangBangClimate::set_away_config(const BangBangClimateTargetTempConfig &away_config) {
   this->supports_away_ = true;
   this->away_config_ = away_config;
 }
-BangBangClimate::BangBangClimate()
-    : idle_trigger_(new Trigger<>()), cool_trigger_(new Trigger<>()), heat_trigger_(new Trigger<>()) {}
+
 void BangBangClimate::set_sensor(sensor::Sensor *sensor) { this->sensor_ = sensor; }
 void BangBangClimate::set_humidity_sensor(sensor::Sensor *humidity_sensor) { this->humidity_sensor_ = humidity_sensor; }
+
 Trigger<> *BangBangClimate::get_idle_trigger() const { return this->idle_trigger_; }
 Trigger<> *BangBangClimate::get_cool_trigger() const { return this->cool_trigger_; }
-void BangBangClimate::set_supports_cool(bool supports_cool) { this->supports_cool_ = supports_cool; }
 Trigger<> *BangBangClimate::get_heat_trigger() const { return this->heat_trigger_; }
+
+void BangBangClimate::set_supports_cool(bool supports_cool) { this->supports_cool_ = supports_cool; }
 void BangBangClimate::set_supports_heat(bool supports_heat) { this->supports_heat_ = supports_heat; }
+
 void BangBangClimate::dump_config() {
   LOG_CLIMATE("", "Bang Bang Climate", this);
   ESP_LOGCONFIG(TAG,

esphome/components/bang_bang/bang_bang_climate.h

@@ -25,14 +25,15 @@ class BangBangClimate : public climate::Climate, public Component {
 
   void set_sensor(sensor::Sensor *sensor);
   void set_humidity_sensor(sensor::Sensor *humidity_sensor);
-  Trigger<> *get_idle_trigger() const;
-  Trigger<> *get_cool_trigger() const;
   void set_supports_cool(bool supports_cool);
-  Trigger<> *get_heat_trigger() const;
   void set_supports_heat(bool supports_heat);
   void set_normal_config(const BangBangClimateTargetTempConfig &normal_config);
   void set_away_config(const BangBangClimateTargetTempConfig &away_config);
 
+  Trigger<> *get_idle_trigger() const;
+  Trigger<> *get_cool_trigger() const;
+  Trigger<> *get_heat_trigger() const;
+
  protected:
   /// Override control to change settings of the climate device.
   void control(const climate::ClimateCall &call) override;
@@ -56,16 +57,10 @@ class BangBangClimate : public climate::Climate, public Component {
    *
    * In idle mode, the controller is assumed to have both heating and cooling disabled.
    */
-  Trigger<> *idle_trigger_;
+  Trigger<> *idle_trigger_{nullptr};
   /** The trigger to call when the controller should switch to cooling mode.
    */
-  Trigger<> *cool_trigger_;
-  /** Whether the controller supports cooling.
-   *
-   * A false value for this attribute means that the controller has no cooling action
-   * (for example a thermostat, where only heating and not-heating is possible).
-   */
-  bool supports_cool_{false};
+  Trigger<> *cool_trigger_{nullptr};
   /** The trigger to call when the controller should switch to heating mode.
    *
    * A null value for this attribute means that the controller has no heating action
@@ -73,15 +68,23 @@ class BangBangClimate : public climate::Climate, public Component {
    * (blinds open) is possible.
    */
   Trigger<> *heat_trigger_{nullptr};
-  bool supports_heat_{false};
   /** A reference to the trigger that was previously active.
    *
    * This is so that the previous trigger can be stopped before enabling a new one.
    */
   Trigger<> *prev_trigger_{nullptr};
 
-  BangBangClimateTargetTempConfig normal_config_{};
+  /** Whether the controller supports cooling/heating
+   *
+   * A false value for this attribute means that the controller has no respective action
+   * (for example a thermostat, where only heating and not-heating is possible).
+   */
+  bool supports_cool_{false};
+  bool supports_heat_{false};
+
   bool supports_away_{false};
+
+  BangBangClimateTargetTempConfig normal_config_{};
   BangBangClimateTargetTempConfig away_config_{};
 };
 

esphome/components/bedjet/bedjet_const.h

@@ -99,9 +99,7 @@ enum BedjetCommand : uint8_t {
 
 static const uint8_t BEDJET_FAN_SPEED_COUNT = 20;
 
-static const char *const BEDJET_FAN_STEP_NAMES[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
-static const std::string BEDJET_FAN_STEP_NAME_STRINGS[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
-static const std::set<std::string> BEDJET_FAN_STEP_NAMES_SET BEDJET_FAN_STEP_NAMES_;
+static constexpr const char *const BEDJET_FAN_STEP_NAMES[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
 
 }  // namespace bedjet
 }  // namespace esphome

esphome/components/bedjet/climate/bedjet_climate.cpp

@@ -8,15 +8,15 @@ namespace bedjet {
 
 using namespace esphome::climate;
 
-static const std::string *bedjet_fan_step_to_fan_mode(const uint8_t fan_step) {
+static const char *bedjet_fan_step_to_fan_mode(const uint8_t fan_step) {
   if (fan_step < BEDJET_FAN_SPEED_COUNT)
-    return &BEDJET_FAN_STEP_NAME_STRINGS[fan_step];
+    return BEDJET_FAN_STEP_NAMES[fan_step];
   return nullptr;
 }
 
-static uint8_t bedjet_fan_speed_to_step(const std::string &fan_step_percent) {
+static uint8_t bedjet_fan_speed_to_step(const char *fan_step_percent) {
   for (int i = 0; i < BEDJET_FAN_SPEED_COUNT; i++) {
-    if (fan_step_percent == BEDJET_FAN_STEP_NAME_STRINGS[i]) {
+    if (strcmp(BEDJET_FAN_STEP_NAMES[i], fan_step_percent) == 0) {
       return i;
     }
   }
@@ -48,7 +48,7 @@ void BedJetClimate::dump_config() {
     ESP_LOGCONFIG(TAG, "   - %s", LOG_STR_ARG(climate_fan_mode_to_string(mode)));
   }
   for (const auto &mode : traits.get_supported_custom_fan_modes()) {
-    ESP_LOGCONFIG(TAG, "   - %s (c)", mode.c_str());
+    ESP_LOGCONFIG(TAG, "   - %s (c)", mode);
   }
 
   ESP_LOGCONFIG(TAG, "  Supported presets:");
@@ -56,7 +56,7 @@ void BedJetClimate::dump_config() {
     ESP_LOGCONFIG(TAG, "   - %s", LOG_STR_ARG(climate_preset_to_string(preset)));
   }
   for (const auto &preset : traits.get_supported_custom_presets()) {
-    ESP_LOGCONFIG(TAG, "   - %s (c)", preset.c_str());
+    ESP_LOGCONFIG(TAG, "   - %s (c)", preset);
   }
 }
 
@@ -79,7 +79,7 @@ void BedJetClimate::reset_state_() {
   this->target_temperature = NAN;
   this->current_temperature = NAN;
   this->preset.reset();
-  this->custom_preset.reset();
+  this->clear_custom_preset_();
   this->publish_state();
 }
 
@@ -120,7 +120,7 @@ void BedJetClimate::control(const ClimateCall &call) {
     if (button_result) {
       this->mode = mode;
       // We're using (custom) preset for Turbo, EXT HT, & M1-3 presets, so changing climate mode will clear those
-      this->custom_preset.reset();
+      this->clear_custom_preset_();
       this->preset.reset();
     }
   }
@@ -144,8 +144,7 @@ void BedJetClimate::control(const ClimateCall &call) {
 
       if (result) {
         this->mode = CLIMATE_MODE_HEAT;
-        this->preset = CLIMATE_PRESET_BOOST;
-        this->custom_preset.reset();
+        this->set_preset_(CLIMATE_PRESET_BOOST);
       }
     } else if (preset == CLIMATE_PRESET_NONE && this->preset.has_value()) {
       if (this->mode == CLIMATE_MODE_HEAT && this->preset == CLIMATE_PRESET_BOOST) {
@@ -153,7 +152,7 @@ void BedJetClimate::control(const ClimateCall &call) {
         result = this->parent_->send_button(heat_button(this->heating_mode_));
         if (result) {
           this->preset.reset();
-          this->custom_preset.reset();
+          this->clear_custom_preset_();
         }
       } else {
         ESP_LOGD(TAG, "Ignoring preset '%s' call; with current mode '%s' and preset '%s'",
@@ -164,28 +163,27 @@ void BedJetClimate::control(const ClimateCall &call) {
       ESP_LOGW(TAG, "Unsupported preset: %d", preset);
       return;
     }
-  } else if (call.get_custom_preset().has_value()) {
-    std::string preset = *call.get_custom_preset();
+  } else if (call.has_custom_preset()) {
+    const char *preset = call.get_custom_preset();
     bool result;
 
-    if (preset == "M1") {
+    if (strcmp(preset, "M1") == 0) {
       result = this->parent_->button_memory1();
-    } else if (preset == "M2") {
+    } else if (strcmp(preset, "M2") == 0) {
       result = this->parent_->button_memory2();
-    } else if (preset == "M3") {
+    } else if (strcmp(preset, "M3") == 0) {
       result = this->parent_->button_memory3();
-    } else if (preset == "LTD HT") {
+    } else if (strcmp(preset, "LTD HT") == 0) {
       result = this->parent_->button_heat();
-    } else if (preset == "EXT HT") {
+    } else if (strcmp(preset, "EXT HT") == 0) {
       result = this->parent_->button_ext_heat();
     } else {
-      ESP_LOGW(TAG, "Unsupported preset: %s", preset.c_str());
+      ESP_LOGW(TAG, "Unsupported preset: %s", preset);
       return;
     }
 
     if (result) {
-      this->custom_preset = preset;
-      this->preset.reset();
+      this->set_custom_preset_(preset);
     }
   }
 
@@ -207,19 +205,16 @@ void BedJetClimate::control(const ClimateCall &call) {
     }
 
     if (result) {
-      this->fan_mode = fan_mode;
-      this->custom_fan_mode.reset();
+      this->set_fan_mode_(fan_mode);
     }
-  } else if (call.get_custom_fan_mode().has_value()) {
-    auto fan_mode = *call.get_custom_fan_mode();
+  } else if (call.has_custom_fan_mode()) {
+    const char *fan_mode = call.get_custom_fan_mode();
     auto fan_index = bedjet_fan_speed_to_step(fan_mode);
     if (fan_index <= 19) {
-      ESP_LOGV(TAG, "[%s] Converted fan mode %s to bedjet fan step %d", this->get_name().c_str(), fan_mode.c_str(),
-               fan_index);
+      ESP_LOGV(TAG, "[%s] Converted fan mode %s to bedjet fan step %d", this->get_name().c_str(), fan_mode, fan_index);
       bool result = this->parent_->set_fan_index(fan_index);
       if (result) {
-        this->custom_fan_mode = fan_mode;
-        this->fan_mode.reset();
+        this->set_custom_fan_mode_(fan_mode);
       }
     }
   }
@@ -245,7 +240,7 @@ void BedJetClimate::on_status(const BedjetStatusPacket *data) {
 
   const auto *fan_mode_name = bedjet_fan_step_to_fan_mode(data->fan_step);
   if (fan_mode_name != nullptr) {
-    this->custom_fan_mode = *fan_mode_name;
+    this->set_custom_fan_mode_(fan_mode_name);
   }
 
   // TODO: Get biorhythm data to determine which preset (M1-3) is running, if any.
@@ -255,7 +250,7 @@ void BedJetClimate::on_status(const BedjetStatusPacket *data) {
       this->mode = CLIMATE_MODE_OFF;
       this->action = CLIMATE_ACTION_IDLE;
       this->fan_mode = CLIMATE_FAN_OFF;
-      this->custom_preset.reset();
+      this->clear_custom_preset_();
       this->preset.reset();
       break;
 
@@ -266,7 +261,7 @@ void BedJetClimate::on_status(const BedjetStatusPacket *data) {
       if (this->heating_mode_ == HEAT_MODE_EXTENDED) {
         this->set_custom_preset_("LTD HT");
       } else {
-        this->custom_preset.reset();
+        this->clear_custom_preset_();
       }
       break;
 
@@ -275,7 +270,7 @@ void BedJetClimate::on_status(const BedjetStatusPacket *data) {
       this->action = CLIMATE_ACTION_HEATING;
       this->preset.reset();
       if (this->heating_mode_ == HEAT_MODE_EXTENDED) {
-        this->custom_preset.reset();
+        this->clear_custom_preset_();
       } else {
         this->set_custom_preset_("EXT HT");
       }
@@ -284,20 +279,19 @@ void BedJetClimate::on_status(const BedjetStatusPacket *data) {
     case MODE_COOL:
       this->mode = CLIMATE_MODE_FAN_ONLY;
       this->action = CLIMATE_ACTION_COOLING;
-      this->custom_preset.reset();
+      this->clear_custom_preset_();
       this->preset.reset();
       break;
 
     case MODE_DRY:
       this->mode = CLIMATE_MODE_DRY;
       this->action = CLIMATE_ACTION_DRYING;
-      this->custom_preset.reset();
+      this->clear_custom_preset_();
       this->preset.reset();
       break;
 
     case MODE_TURBO:
-      this->preset = CLIMATE_PRESET_BOOST;
-      this->custom_preset.reset();
+      this->set_preset_(CLIMATE_PRESET_BOOST);
       this->mode = CLIMATE_MODE_HEAT;
       this->action = CLIMATE_ACTION_HEATING;
       break;

esphome/components/bedjet/climate/bedjet_climate.h

@@ -33,8 +33,7 @@ class BedJetClimate : public climate::Climate, public BedJetClient, public Polli
 
   climate::ClimateTraits traits() override {
     auto traits = climate::ClimateTraits();
-    traits.set_supports_action(true);
-    traits.set_supports_current_temperature(true);
+    traits.add_feature_flags(climate::CLIMATE_SUPPORTS_ACTION | climate::CLIMATE_SUPPORTS_CURRENT_TEMPERATURE);
     traits.set_supported_modes({
         climate::CLIMATE_MODE_OFF,
         climate::CLIMATE_MODE_HEAT,
@@ -44,28 +43,20 @@ class BedJetClimate : public climate::Climate, public BedJetClient, public Polli
     });
 
     // It would be better if we had a slider for the fan modes.
-    traits.set_supported_custom_fan_modes(BEDJET_FAN_STEP_NAMES_SET);
+    traits.set_supported_custom_fan_modes(BEDJET_FAN_STEP_NAMES);
     traits.set_supported_presets({
         // If we support NONE, then have to decide what happens if the user switches to it (turn off?)
         // climate::CLIMATE_PRESET_NONE,
         // Climate doesn't have a "TURBO" mode, but we can use the BOOST preset instead.
         climate::CLIMATE_PRESET_BOOST,
     });
+    // String literals are stored in rodata and valid for program lifetime
     traits.set_supported_custom_presets({
-        // We could fetch biodata from bedjet and set these names that way.
-        // But then we have to invert the lookup in order to send the right preset.
-        // For now, we can leave them as M1-3 to match the remote buttons.
-        // EXT HT added to match remote button.
-        "EXT HT",
+        this->heating_mode_ == HEAT_MODE_EXTENDED ? "LTD HT" : "EXT HT",
         "M1",
         "M2",
         "M3",
     });
-    if (this->heating_mode_ == HEAT_MODE_EXTENDED) {
-      traits.add_supported_custom_preset("LTD HT");
-    } else {
-      traits.add_supported_custom_preset("EXT HT");
-    }
     traits.set_visual_min_temperature(19.0);
     traits.set_visual_max_temperature(43.0);
     traits.set_visual_temperature_step(1.0);

esphome/components/bh1900nux/bh1900nux.cpp

@@ -0,0 +1,54 @@
+#include "esphome/core/log.h"
+#include "bh1900nux.h"
+
+namespace esphome {
+namespace bh1900nux {
+
+static const char *const TAG = "bh1900nux.sensor";
+
+// I2C Registers
+static const uint8_t TEMPERATURE_REG = 0x00;
+static const uint8_t CONFIG_REG = 0x01;            // Not used and supported yet
+static const uint8_t TEMPERATURE_LOW_REG = 0x02;   // Not used and supported yet
+static const uint8_t TEMPERATURE_HIGH_REG = 0x03;  // Not used and supported yet
+static const uint8_t SOFT_RESET_REG = 0x04;
+
+// I2C Command payloads
+static const uint8_t SOFT_RESET_PAYLOAD = 0x01;  // Soft Reset value
+
+static const float SENSOR_RESOLUTION = 0.0625f;  // Sensor resolution per bit in degrees celsius
+
+void BH1900NUXSensor::setup() {
+  // Initialize I2C device
+  i2c::ErrorCode result_code =
+      this->write_register(SOFT_RESET_REG, &SOFT_RESET_PAYLOAD, 1);  // Software Reset to check communication
+  if (result_code != i2c::ERROR_OK) {
+    this->mark_failed(ESP_LOG_MSG_COMM_FAIL);
+    return;
+  }
+}
+
+void BH1900NUXSensor::update() {
+  uint8_t temperature_raw[2];
+  if (this->read_register(TEMPERATURE_REG, temperature_raw, 2) != i2c::ERROR_OK) {
+    ESP_LOGE(TAG, ESP_LOG_MSG_COMM_FAIL);
+    return;
+  }
+
+  // Combined raw value, unsigned and unaligned 16 bit
+  // Temperature is represented in just 12 bits, shift needed
+  int16_t raw_temperature_register_value = encode_uint16(temperature_raw[0], temperature_raw[1]);
+  raw_temperature_register_value >>= 4;
+  float temperature_value = raw_temperature_register_value * SENSOR_RESOLUTION;  // Apply sensor resolution
+
+  this->publish_state(temperature_value);
+}
+
+void BH1900NUXSensor::dump_config() {
+  LOG_SENSOR("", "BH1900NUX", this);
+  LOG_I2C_DEVICE(this);
+  LOG_UPDATE_INTERVAL(this);
+}
+
+}  // namespace bh1900nux
+}  // namespace esphome

esphome/components/bh1900nux/bh1900nux.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/components/sensor/sensor.h"
+#include "esphome/components/i2c/i2c.h"
+
+namespace esphome {
+namespace bh1900nux {
+
+class BH1900NUXSensor : public sensor::Sensor, public PollingComponent, public i2c::I2CDevice {
+ public:
+  void setup() override;
+  void update() override;
+  void dump_config() override;
+};
+
+}  // namespace bh1900nux
+}  // namespace esphome

esphome/components/bh1900nux/sensor.py

@@ -0,0 +1,34 @@
+import esphome.codegen as cg
+from esphome.components import i2c, sensor
+import esphome.config_validation as cv
+from esphome.const import (
+    DEVICE_CLASS_TEMPERATURE,
+    STATE_CLASS_MEASUREMENT,
+    UNIT_CELSIUS,
+)
+
+DEPENDENCIES = ["i2c"]
+CODEOWNERS = ["@B48D81EFCC"]
+
+sensor_ns = cg.esphome_ns.namespace("bh1900nux")
+BH1900NUXSensor = sensor_ns.class_(
+    "BH1900NUXSensor", cg.PollingComponent, i2c.I2CDevice
+)
+
+CONFIG_SCHEMA = (
+    sensor.sensor_schema(
+        BH1900NUXSensor,
+        accuracy_decimals=1,
+        unit_of_measurement=UNIT_CELSIUS,
+        device_class=DEVICE_CLASS_TEMPERATURE,
+        state_class=STATE_CLASS_MEASUREMENT,
+    )
+    .extend(cv.polling_component_schema("60s"))
+    .extend(i2c.i2c_device_schema(0x48))
+)
+
+
+async def to_code(config):
+    var = await sensor.new_sensor(config)
+    await cg.register_component(var, config)
+    await i2c.register_i2c_device(var, config)

esphome/components/binary_sensor/__init__.py

@@ -155,6 +155,7 @@ DelayedOffFilter = binary_sensor_ns.class_("DelayedOffFilter", Filter, cg.Compon
 InvertFilter = binary_sensor_ns.class_("InvertFilter", Filter)
 AutorepeatFilter = binary_sensor_ns.class_("AutorepeatFilter", Filter, cg.Component)
 LambdaFilter = binary_sensor_ns.class_("LambdaFilter", Filter)
+StatelessLambdaFilter = binary_sensor_ns.class_("StatelessLambdaFilter", Filter)
 SettleFilter = binary_sensor_ns.class_("SettleFilter", Filter, cg.Component)
 
 _LOGGER = getLogger(__name__)
@@ -264,20 +265,31 @@ async def delayed_off_filter_to_code(config, filter_id):
     ),
 )
 async def autorepeat_filter_to_code(config, filter_id):
-    timings = []
     if len(config) > 0:
-        timings.extend(
-            (conf[CONF_DELAY], conf[CONF_TIME_OFF], conf[CONF_TIME_ON])
-            for conf in config
-        )
-    else:
-        timings.append(
-            (
-                cv.time_period_str_unit(DEFAULT_DELAY).total_milliseconds,
-                cv.time_period_str_unit(DEFAULT_TIME_OFF).total_milliseconds,
-                cv.time_period_str_unit(DEFAULT_TIME_ON).total_milliseconds,
+        timings = [
+            cg.StructInitializer(
+                cg.MockObj("AutorepeatFilterTiming", "esphome::binary_sensor::"),
+                ("delay", conf[CONF_DELAY]),
+                ("time_off", conf[CONF_TIME_OFF]),
+                ("time_on", conf[CONF_TIME_ON]),
             )
-        )
+            for conf in config
+        ]
+    else:
+        timings = [
+            cg.StructInitializer(
+                cg.MockObj("AutorepeatFilterTiming", "esphome::binary_sensor::"),
+                ("delay", cv.time_period_str_unit(DEFAULT_DELAY).total_milliseconds),
+                (
+                    "time_off",
+                    cv.time_period_str_unit(DEFAULT_TIME_OFF).total_milliseconds,
+                ),
+                (
+                    "time_on",
+                    cv.time_period_str_unit(DEFAULT_TIME_ON).total_milliseconds,
+                ),
+            )
+        ]
     var = cg.new_Pvariable(filter_id, timings)
     await cg.register_component(var, {})
     return var
@@ -288,7 +300,7 @@ async def lambda_filter_to_code(config, filter_id):
     lambda_ = await cg.process_lambda(
         config, [(bool, "x")], return_type=cg.optional.template(bool)
     )
-    return cg.new_Pvariable(filter_id, lambda_)
+    return automation.new_lambda_pvariable(filter_id, lambda_, StatelessLambdaFilter)
 
 
 @register_filter(
@@ -536,11 +548,6 @@ def binary_sensor_schema(
     return _BINARY_SENSOR_SCHEMA.extend(schema)
 
 
-# Remove before 2025.11.0
-BINARY_SENSOR_SCHEMA = binary_sensor_schema()
-BINARY_SENSOR_SCHEMA.add_extra(cv.deprecated_schema_constant("binary_sensor"))
-
-
 async def setup_binary_sensor_core_(var, config):
     await setup_entity(var, config, "binary_sensor")
 

esphome/components/binary_sensor/automation.h

@@ -2,11 +2,11 @@
 
 #include <cinttypes>
 #include <utility>
-#include <vector>
 
 #include "esphome/core/component.h"
 #include "esphome/core/automation.h"
 #include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
 #include "esphome/components/binary_sensor/binary_sensor.h"
 
 namespace esphome {
@@ -92,8 +92,8 @@ class DoubleClickTrigger : public Trigger<> {
 
 class MultiClickTrigger : public Trigger<>, public Component {
  public:
-  explicit MultiClickTrigger(BinarySensor *parent, std::vector<MultiClickTriggerEvent> timing)
-      : parent_(parent), timing_(std::move(timing)) {}
+  explicit MultiClickTrigger(BinarySensor *parent, std::initializer_list<MultiClickTriggerEvent> timing)
+      : parent_(parent), timing_(timing) {}
 
   void setup() override {
     this->last_state_ = this->parent_->get_state_default(false);
@@ -115,7 +115,7 @@ class MultiClickTrigger : public Trigger<>, public Component {
   void trigger_();
 
   BinarySensor *parent_;
-  std::vector<MultiClickTriggerEvent> timing_;
+  FixedVector<MultiClickTriggerEvent> timing_;
   uint32_t invalid_cooldown_{1000};
   optional<size_t> at_index_{};
   bool last_state_{false};
@@ -141,7 +141,7 @@ class StateChangeTrigger : public Trigger<optional<bool>, optional<bool> > {
 template<typename... Ts> class BinarySensorCondition : public Condition<Ts...> {
  public:
   BinarySensorCondition(BinarySensor *parent, bool state) : parent_(parent), state_(state) {}
-  bool check(Ts... x) override { return this->parent_->state == this->state_; }
+  bool check(const Ts &...x) override { return this->parent_->state == this->state_; }
 
  protected:
   BinarySensor *parent_;
@@ -153,7 +153,7 @@ template<typename... Ts> class BinarySensorPublishAction : public Action<Ts...>
   explicit BinarySensorPublishAction(BinarySensor *sensor) : sensor_(sensor) {}
   TEMPLATABLE_VALUE(bool, state)
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     auto val = this->state_.value(x...);
     this->sensor_->publish_state(val);
   }
@@ -166,7 +166,7 @@ template<typename... Ts> class BinarySensorInvalidateAction : public Action<Ts..
  public:
   explicit BinarySensorInvalidateAction(BinarySensor *sensor) : sensor_(sensor) {}
 
-  void play(Ts... x) override { this->sensor_->invalidate_state(); }
+  void play(const Ts &...x) override { this->sensor_->invalidate_state(); }
 
  protected:
   BinarySensor *sensor_;

esphome/components/binary_sensor/binary_sensor.cpp

@@ -1,4 +1,6 @@
 #include "binary_sensor.h"
+#include "esphome/core/defines.h"
+#include "esphome/core/controller_registry.h"
 #include "esphome/core/log.h"
 
 namespace esphome {
@@ -37,6 +39,9 @@ void BinarySensor::send_state_internal(bool new_state) {
   // Note that set_state_ de-dups and will only trigger callbacks if the state has actually changed
   if (this->set_state_(new_state)) {
     ESP_LOGD(TAG, "'%s': New state is %s", this->get_name().c_str(), ONOFF(new_state));
+#if defined(USE_BINARY_SENSOR) && defined(USE_CONTROLLER_REGISTRY)
+    ControllerRegistry::notify_binary_sensor_update(this);
+#endif
   }
 }
 
@@ -51,7 +56,7 @@ void BinarySensor::add_filter(Filter *filter) {
     last_filter->next_ = filter;
   }
 }
-void BinarySensor::add_filters(const std::vector<Filter *> &filters) {
+void BinarySensor::add_filters(std::initializer_list<Filter *> filters) {
   for (Filter *filter : filters) {
     this->add_filter(filter);
   }

esphome/components/binary_sensor/binary_sensor.h

@@ -4,7 +4,7 @@
 #include "esphome/core/helpers.h"
 #include "esphome/components/binary_sensor/filter.h"
 
-#include <vector>
+#include <initializer_list>
 
 namespace esphome {
 
@@ -48,7 +48,7 @@ class BinarySensor : public StatefulEntityBase<bool>, public EntityBase_DeviceCl
   void publish_initial_state(bool new_state);
 
   void add_filter(Filter *filter);
-  void add_filters(const std::vector<Filter *> &filters);
+  void add_filters(std::initializer_list<Filter *> filters);
 
   // ========== INTERNAL METHODS ==========
   // (In most use cases you won't need these)

esphome/components/binary_sensor/filter.cpp

@@ -1,7 +1,6 @@
 #include "filter.h"
 
 #include "binary_sensor.h"
-#include <utility>
 
 namespace esphome {
 
@@ -68,7 +67,7 @@ float DelayedOffFilter::get_setup_priority() const { return setup_priority::HARD
 
 optional<bool> InvertFilter::new_value(bool value) { return !value; }
 
-AutorepeatFilter::AutorepeatFilter(std::vector<AutorepeatFilterTiming> timings) : timings_(std::move(timings)) {}
+AutorepeatFilter::AutorepeatFilter(std::initializer_list<AutorepeatFilterTiming> timings) : timings_(timings) {}
 
 optional<bool> AutorepeatFilter::new_value(bool value) {
   if (value) {

esphome/components/binary_sensor/filter.h

@@ -4,8 +4,6 @@
 #include "esphome/core/component.h"
 #include "esphome/core/helpers.h"
 
-#include <vector>
-
 namespace esphome {
 
 namespace binary_sensor {
@@ -82,11 +80,6 @@ class InvertFilter : public Filter {
 };
 
 struct AutorepeatFilterTiming {
-  AutorepeatFilterTiming(uint32_t delay, uint32_t off, uint32_t on) {
-    this->delay = delay;
-    this->time_off = off;
-    this->time_on = on;
-  }
   uint32_t delay;
   uint32_t time_off;
   uint32_t time_on;
@@ -94,7 +87,7 @@ struct AutorepeatFilterTiming {
 
 class AutorepeatFilter : public Filter, public Component {
  public:
-  explicit AutorepeatFilter(std::vector<AutorepeatFilterTiming> timings);
+  explicit AutorepeatFilter(std::initializer_list<AutorepeatFilterTiming> timings);
 
   optional<bool> new_value(bool value) override;
 
@@ -104,7 +97,7 @@ class AutorepeatFilter : public Filter, public Component {
   void next_timing_();
   void next_value_(bool val);
 
-  std::vector<AutorepeatFilterTiming> timings_;
+  FixedVector<AutorepeatFilterTiming> timings_;
   uint8_t active_timing_{0};
 };
 
@@ -118,6 +111,21 @@ class LambdaFilter : public Filter {
   std::function<optional<bool>(bool)> f_;
 };
 
+/** Optimized lambda filter for stateless lambdas (no capture).
+ *
+ * Uses function pointer instead of std::function to reduce memory overhead.
+ * Memory: 4 bytes (function pointer on 32-bit) vs 32 bytes (std::function).
+ */
+class StatelessLambdaFilter : public Filter {
+ public:
+  explicit StatelessLambdaFilter(optional<bool> (*f)(bool)) : f_(f) {}
+
+  optional<bool> new_value(bool value) override { return this->f_(value); }
+
+ protected:
+  optional<bool> (*f_)(bool);
+};
+
 class SettleFilter : public Filter, public Component {
  public:
   optional<bool> new_value(bool value) override;

esphome/components/bl0906/bl0906.cpp

@@ -97,10 +97,10 @@ void BL0906::handle_actions_() {
     return;
   }
   ActionCallbackFuncPtr ptr_func = nullptr;
-  for (int i = 0; i < this->action_queue_.size(); i++) {
+  for (size_t i = 0; i < this->action_queue_.size(); i++) {
     ptr_func = this->action_queue_[i];
     if (ptr_func) {
-      ESP_LOGI(TAG, "HandleActionCallback[%d]", i);
+      ESP_LOGI(TAG, "HandleActionCallback[%zu]", i);
       (this->*ptr_func)();
     }
   }

esphome/components/bl0906/bl0906.h

@@ -89,7 +89,7 @@ class BL0906 : public PollingComponent, public uart::UARTDevice {
 
 template<typename... Ts> class ResetEnergyAction : public Action<Ts...>, public Parented<BL0906> {
  public:
-  void play(Ts... x) override { this->parent_->enqueue_action_(&BL0906::reset_energy_); }
+  void play(const Ts &...x) override { this->parent_->enqueue_action_(&BL0906::reset_energy_); }
 };
 
 }  // namespace bl0906

esphome/components/bl0942/bl0942.cpp

@@ -51,7 +51,7 @@ void BL0942::loop() {
   if (!avail) {
     return;
   }
-  if (avail < sizeof(buffer)) {
+  if (static_cast<size_t>(avail) < sizeof(buffer)) {
     if (!this->rx_start_) {
       this->rx_start_ = millis();
     } else if (millis() > this->rx_start_ + PKT_TIMEOUT_MS) {
@@ -148,7 +148,7 @@ void BL0942::setup() {
 
   this->write_reg_(BL0942_REG_USR_WRPROT, 0);
 
-  if (this->read_reg_(BL0942_REG_MODE) != mode)
+  if (static_cast<uint32_t>(this->read_reg_(BL0942_REG_MODE)) != mode)
     this->status_set_warning(LOG_STR("BL0942 setup failed!"));
 
   this->flush();

esphome/components/ble_client/automation.h

@@ -96,8 +96,11 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
   BLEClientWriteAction(BLEClient *ble_client) {
     ble_client->register_ble_node(this);
     ble_client_ = ble_client;
+    this->construct_simple_value_();
   }
 
+  ~BLEClientWriteAction() { this->destroy_simple_value_(); }
+
   void set_service_uuid16(uint16_t uuid) { this->service_uuid_ = espbt::ESPBTUUID::from_uint16(uuid); }
   void set_service_uuid32(uint32_t uuid) { this->service_uuid_ = espbt::ESPBTUUID::from_uint32(uuid); }
   void set_service_uuid128(uint8_t *uuid) { this->service_uuid_ = espbt::ESPBTUUID::from_raw(uuid); }
@@ -106,22 +109,26 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
   void set_char_uuid32(uint32_t uuid) { this->char_uuid_ = espbt::ESPBTUUID::from_uint32(uuid); }
   void set_char_uuid128(uint8_t *uuid) { this->char_uuid_ = espbt::ESPBTUUID::from_raw(uuid); }
 
-  void set_value_template(std::function<std::vector<uint8_t>(Ts...)> func) {
-    this->value_template_ = std::move(func);
-    has_simple_value_ = false;
+  void set_value_template(std::vector<uint8_t> (*func)(Ts...)) {
+    this->destroy_simple_value_();
+    this->value_.template_func = func;
+    this->has_simple_value_ = false;
   }
 
   void set_value_simple(const std::vector<uint8_t> &value) {
-    this->value_simple_ = value;
-    has_simple_value_ = true;
+    if (!this->has_simple_value_) {
+      this->construct_simple_value_();
+    }
+    this->value_.simple = value;
+    this->has_simple_value_ = true;
   }
 
-  void play(Ts... x) override {}
+  void play(const Ts &...x) override {}
 
-  void play_complex(Ts... x) override {
+  void play_complex(const Ts &...x) override {
     this->num_running_++;
     this->var_ = std::make_tuple(x...);
-    auto value = this->has_simple_value_ ? this->value_simple_ : this->value_template_(x...);
+    auto value = this->has_simple_value_ ? this->value_.simple : this->value_.template_func(x...);
     // on write failure, continue the automation chain rather than stopping so that e.g. disconnect can work.
     if (!write(value))
       this->play_next_(x...);
@@ -194,10 +201,22 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
   }
 
  private:
+  void construct_simple_value_() { new (&this->value_.simple) std::vector<uint8_t>(); }
+
+  void destroy_simple_value_() {
+    if (this->has_simple_value_) {
+      this->value_.simple.~vector();
+    }
+  }
+
   BLEClient *ble_client_;
   bool has_simple_value_ = true;
-  std::vector<uint8_t> value_simple_;
-  std::function<std::vector<uint8_t>(Ts...)> value_template_{};
+  union Value {
+    std::vector<uint8_t> simple;
+    std::vector<uint8_t> (*template_func)(Ts...);
+    Value() {}   // trivial constructor
+    ~Value() {}  // trivial destructor - we manage lifetime via discriminator
+  } value_;
   espbt::ESPBTUUID service_uuid_;
   espbt::ESPBTUUID char_uuid_;
   std::tuple<Ts...> var_{};
@@ -210,12 +229,12 @@ template<typename... Ts> class BLEClientPasskeyReplyAction : public Action<Ts...
  public:
   BLEClientPasskeyReplyAction(BLEClient *ble_client) { parent_ = ble_client; }
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     uint32_t passkey;
     if (has_simple_value_) {
-      passkey = this->value_simple_;
+      passkey = this->value_.simple;
     } else {
-      passkey = this->value_template_(x...);
+      passkey = this->value_.template_func(x...);
     }
     if (passkey > 999999)
       return;
@@ -224,59 +243,63 @@ template<typename... Ts> class BLEClientPasskeyReplyAction : public Action<Ts...
     esp_ble_passkey_reply(remote_bda, true, passkey);
   }
 
-  void set_value_template(std::function<uint32_t(Ts...)> func) {
-    this->value_template_ = std::move(func);
-    has_simple_value_ = false;
+  void set_value_template(uint32_t (*func)(Ts...)) {
+    this->value_.template_func = func;
+    this->has_simple_value_ = false;
   }
 
   void set_value_simple(const uint32_t &value) {
-    this->value_simple_ = value;
-    has_simple_value_ = true;
+    this->value_.simple = value;
+    this->has_simple_value_ = true;
   }
 
  private:
   BLEClient *parent_{nullptr};
   bool has_simple_value_ = true;
-  uint32_t value_simple_{0};
-  std::function<uint32_t(Ts...)> value_template_{};
+  union {
+    uint32_t simple;
+    uint32_t (*template_func)(Ts...);
+  } value_{.simple = 0};
 };
 
 template<typename... Ts> class BLEClientNumericComparisonReplyAction : public Action<Ts...> {
  public:
   BLEClientNumericComparisonReplyAction(BLEClient *ble_client) { parent_ = ble_client; }
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     esp_bd_addr_t remote_bda;
     memcpy(remote_bda, parent_->get_remote_bda(), sizeof(esp_bd_addr_t));
     if (has_simple_value_) {
-      esp_ble_confirm_reply(remote_bda, this->value_simple_);
+      esp_ble_confirm_reply(remote_bda, this->value_.simple);
     } else {
-      esp_ble_confirm_reply(remote_bda, this->value_template_(x...));
+      esp_ble_confirm_reply(remote_bda, this->value_.template_func(x...));
     }
   }
 
-  void set_value_template(std::function<bool(Ts...)> func) {
-    this->value_template_ = std::move(func);
-    has_simple_value_ = false;
+  void set_value_template(bool (*func)(Ts...)) {
+    this->value_.template_func = func;
+    this->has_simple_value_ = false;
   }
 
   void set_value_simple(const bool &value) {
-    this->value_simple_ = value;
-    has_simple_value_ = true;
+    this->value_.simple = value;
+    this->has_simple_value_ = true;
   }
 
  private:
   BLEClient *parent_{nullptr};
   bool has_simple_value_ = true;
-  bool value_simple_{false};
-  std::function<bool(Ts...)> value_template_{};
+  union {
+    bool simple;
+    bool (*template_func)(Ts...);
+  } value_{.simple = false};
 };
 
 template<typename... Ts> class BLEClientRemoveBondAction : public Action<Ts...> {
  public:
   BLEClientRemoveBondAction(BLEClient *ble_client) { parent_ = ble_client; }
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     esp_bd_addr_t remote_bda;
     memcpy(remote_bda, parent_->get_remote_bda(), sizeof(esp_bd_addr_t));
     esp_ble_remove_bond_device(remote_bda);
@@ -311,9 +334,9 @@ template<typename... Ts> class BLEClientConnectAction : public Action<Ts...>, pu
   }
 
   // not used since we override play_complex_
-  void play(Ts... x) override {}
+  void play(const Ts &...x) override {}
 
-  void play_complex(Ts... x) override {
+  void play_complex(const Ts &...x) override {
     // it makes no sense to have multiple instances of this running at the same time.
     // this would occur only if the same automation was re-triggered while still
     // running. So just cancel the second chain if this is detected.
@@ -356,9 +379,9 @@ template<typename... Ts> class BLEClientDisconnectAction : public Action<Ts...>,
   }
 
   // not used since we override play_complex_
-  void play(Ts... x) override {}
+  void play(const Ts &...x) override {}
 
-  void play_complex(Ts... x) override {
+  void play_complex(const Ts &...x) override {
     this->num_running_++;
     if (this->node_state == espbt::ClientState::IDLE) {
       this->play_next_(x...);

esphome/components/ble_client/sensor/ble_sensor.cpp

@@ -77,6 +77,9 @@ void BLESensor::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t ga
         }
       } else {
         this->node_state = espbt::ClientState::ESTABLISHED;
+        // For non-notify characteristics, trigger an immediate read after service discovery
+        // to avoid peripherals disconnecting due to inactivity
+        this->update();
       }
       break;
     }
@@ -117,9 +120,9 @@ void BLESensor::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t ga
 }
 
 float BLESensor::parse_data_(uint8_t *value, uint16_t value_len) {
-  if (this->data_to_value_func_.has_value()) {
+  if (this->has_data_to_value_) {
     std::vector<uint8_t> data(value, value + value_len);
-    return (*this->data_to_value_func_)(data);
+    return this->data_to_value_func_(data);
   } else {
     return value[0];
   }

esphome/components/ble_client/sensor/ble_sensor.h

@@ -15,8 +15,6 @@ namespace ble_client {
 
 namespace espbt = esphome::esp32_ble_tracker;
 
-using data_to_value_t = std::function<float(std::vector<uint8_t>)>;
-
 class BLESensor : public sensor::Sensor, public PollingComponent, public BLEClientNode {
  public:
   void loop() override;
@@ -33,13 +31,17 @@ class BLESensor : public sensor::Sensor, public PollingComponent, public BLEClie
   void set_descr_uuid16(uint16_t uuid) { this->descr_uuid_ = espbt::ESPBTUUID::from_uint16(uuid); }
   void set_descr_uuid32(uint32_t uuid) { this->descr_uuid_ = espbt::ESPBTUUID::from_uint32(uuid); }
   void set_descr_uuid128(uint8_t *uuid) { this->descr_uuid_ = espbt::ESPBTUUID::from_raw(uuid); }
-  void set_data_to_value(data_to_value_t &&lambda) { this->data_to_value_func_ = lambda; }
+  void set_data_to_value(float (*lambda)(const std::vector<uint8_t> &)) {
+    this->data_to_value_func_ = lambda;
+    this->has_data_to_value_ = true;
+  }
   void set_enable_notify(bool notify) { this->notify_ = notify; }
   uint16_t handle;
 
  protected:
   float parse_data_(uint8_t *value, uint16_t value_len);
-  optional<data_to_value_t> data_to_value_func_{};
+  bool has_data_to_value_{false};
+  float (*data_to_value_func_)(const std::vector<uint8_t> &){};
   bool notify_;
   espbt::ESPBTUUID service_uuid_;
   espbt::ESPBTUUID char_uuid_;

esphome/components/ble_client/text_sensor/ble_text_sensor.cpp

@@ -79,6 +79,9 @@ void BLETextSensor::gattc_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_
         }
       } else {
         this->node_state = espbt::ClientState::ESTABLISHED;
+        // For non-notify characteristics, trigger an immediate read after service discovery
+        // to avoid peripherals disconnecting due to inactivity
+        this->update();
       }
       break;
     }

esphome/components/ble_nus/__init__.py

@@ -0,0 +1,29 @@
+import esphome.codegen as cg
+from esphome.components.zephyr import zephyr_add_prj_conf
+import esphome.config_validation as cv
+from esphome.const import CONF_ID, CONF_LOGS, CONF_TYPE
+
+AUTO_LOAD = ["zephyr_ble_server"]
+CODEOWNERS = ["@tomaszduda23"]
+
+ble_nus_ns = cg.esphome_ns.namespace("ble_nus")
+BLENUS = ble_nus_ns.class_("BLENUS", cg.Component)
+
+CONFIG_SCHEMA = cv.All(
+    cv.Schema(
+        {
+            cv.GenerateID(): cv.declare_id(BLENUS),
+            cv.Optional(CONF_TYPE, default=CONF_LOGS): cv.one_of(
+                *[CONF_LOGS], lower=True
+            ),
+        }
+    ).extend(cv.COMPONENT_SCHEMA),
+    cv.only_with_framework("zephyr"),
+)
+
+
+async def to_code(config):
+    var = cg.new_Pvariable(config[CONF_ID])
+    zephyr_add_prj_conf("BT_NUS", True)
+    cg.add(var.set_expose_log(config[CONF_TYPE] == CONF_LOGS))
+    await cg.register_component(var, config)

esphome/components/ble_nus/ble_nus.cpp

@@ -0,0 +1,157 @@
+#ifdef USE_ZEPHYR
+#include "ble_nus.h"
+#include <zephyr/kernel.h>
+#include <bluetooth/services/nus.h>
+#include "esphome/core/log.h"
+#ifdef USE_LOGGER
+#include "esphome/components/logger/logger.h"
+#include "esphome/core/application.h"
+#endif
+#include <zephyr/sys/ring_buffer.h>
+
+namespace esphome::ble_nus {
+
+constexpr size_t BLE_TX_BUF_SIZE = 2048;
+
+// NOLINTBEGIN(cppcoreguidelines-avoid-non-const-global-variables)
+BLENUS *global_ble_nus;
+RING_BUF_DECLARE(global_ble_tx_ring_buf, BLE_TX_BUF_SIZE);
+// NOLINTEND(cppcoreguidelines-avoid-non-const-global-variables)
+
+static const char *const TAG = "ble_nus";
+
+size_t BLENUS::write_array(const uint8_t *data, size_t len) {
+  if (atomic_get(&this->tx_status_) == TX_DISABLED) {
+    return 0;
+  }
+  return ring_buf_put(&global_ble_tx_ring_buf, data, len);
+}
+
+void BLENUS::connected(bt_conn *conn, uint8_t err) {
+  if (err == 0) {
+    global_ble_nus->conn_.store(bt_conn_ref(conn));
+  }
+}
+
+void BLENUS::disconnected(bt_conn *conn, uint8_t reason) {
+  if (global_ble_nus->conn_) {
+    bt_conn_unref(global_ble_nus->conn_.load());
+    // Connection array is global static.
+    // Reference can be kept even if disconnected.
+  }
+}
+
+void BLENUS::tx_callback(bt_conn *conn) {
+  atomic_cas(&global_ble_nus->tx_status_, TX_BUSY, TX_ENABLED);
+  ESP_LOGVV(TAG, "Sent operation completed");
+}
+
+void BLENUS::send_enabled_callback(bt_nus_send_status status) {
+  switch (status) {
+    case BT_NUS_SEND_STATUS_ENABLED:
+      atomic_set(&global_ble_nus->tx_status_, TX_ENABLED);
+#ifdef USE_LOGGER
+      if (global_ble_nus->expose_log_) {
+        App.schedule_dump_config();
+      }
+#endif
+      ESP_LOGD(TAG, "NUS notification has been enabled");
+      break;
+    case BT_NUS_SEND_STATUS_DISABLED:
+      atomic_set(&global_ble_nus->tx_status_, TX_DISABLED);
+      ESP_LOGD(TAG, "NUS notification has been disabled");
+      break;
+  }
+}
+
+void BLENUS::rx_callback(bt_conn *conn, const uint8_t *const data, uint16_t len) {
+  ESP_LOGD(TAG, "Received %d bytes.", len);
+}
+
+void BLENUS::setup() {
+  bt_nus_cb callbacks = {
+      .received = rx_callback,
+      .sent = tx_callback,
+      .send_enabled = send_enabled_callback,
+  };
+
+  bt_nus_init(&callbacks);
+
+  static bt_conn_cb conn_callbacks = {
+      .connected = BLENUS::connected,
+      .disconnected = BLENUS::disconnected,
+  };
+
+  bt_conn_cb_register(&conn_callbacks);
+
+  global_ble_nus = this;
+#ifdef USE_LOGGER
+  if (logger::global_logger != nullptr && this->expose_log_) {
+    logger::global_logger->add_on_log_callback(
+        [this](int level, const char *tag, const char *message, size_t message_len) {
+          this->write_array(reinterpret_cast<const uint8_t *>(message), message_len);
+          const char c = '\n';
+          this->write_array(reinterpret_cast<const uint8_t *>(&c), 1);
+        });
+  }
+
+#endif
+}
+
+void BLENUS::dump_config() {
+  ESP_LOGCONFIG(TAG, "ble nus:");
+  ESP_LOGCONFIG(TAG, "  log: %s", YESNO(this->expose_log_));
+  uint32_t mtu = 0;
+  bt_conn *conn = this->conn_.load();
+  if (conn) {
+    mtu = bt_nus_get_mtu(conn);
+  }
+  ESP_LOGCONFIG(TAG, "  MTU: %u", mtu);
+}
+
+void BLENUS::loop() {
+  if (ring_buf_is_empty(&global_ble_tx_ring_buf)) {
+    return;
+  }
+
+  if (!atomic_cas(&this->tx_status_, TX_ENABLED, TX_BUSY)) {
+    if (atomic_get(&this->tx_status_) == TX_DISABLED) {
+      ring_buf_reset(&global_ble_tx_ring_buf);
+    }
+    return;
+  }
+
+  bt_conn *conn = this->conn_.load();
+  if (conn) {
+    conn = bt_conn_ref(conn);
+  }
+
+  if (nullptr == conn) {
+    atomic_cas(&this->tx_status_, TX_BUSY, TX_ENABLED);
+    return;
+  }
+
+  uint32_t req_len = bt_nus_get_mtu(conn);
+
+  uint8_t *buf;
+  uint32_t size = ring_buf_get_claim(&global_ble_tx_ring_buf, &buf, req_len);
+
+  int err, err2;
+
+  err = bt_nus_send(conn, buf, size);
+  err2 = ring_buf_get_finish(&global_ble_tx_ring_buf, size);
+  if (err2) {
+    // It should no happen.
+    ESP_LOGE(TAG, "Size %u exceeds valid bytes in the ring buffer (%d error)", size, err2);
+  }
+  if (err == 0) {
+    ESP_LOGVV(TAG, "Sent %d bytes", size);
+  } else {
+    ESP_LOGE(TAG, "Failed to send %d bytes (%d error)", size, err);
+    atomic_cas(&this->tx_status_, TX_BUSY, TX_ENABLED);
+  }
+  bt_conn_unref(conn);
+}
+
+}  // namespace esphome::ble_nus
+#endif

esphome/components/ble_nus/ble_nus.h

@@ -0,0 +1,37 @@
+#pragma once
+#ifdef USE_ZEPHYR
+#include "esphome/core/defines.h"
+#include "esphome/core/component.h"
+#include <shell/shell_bt_nus.h>
+#include <atomic>
+
+namespace esphome::ble_nus {
+
+class BLENUS : public Component {
+  enum TxStatus {
+    TX_DISABLED,
+    TX_ENABLED,
+    TX_BUSY,
+  };
+
+ public:
+  void setup() override;
+  void dump_config() override;
+  void loop() override;
+  size_t write_array(const uint8_t *data, size_t len);
+  void set_expose_log(bool expose_log) { this->expose_log_ = expose_log; }
+
+ protected:
+  static void send_enabled_callback(bt_nus_send_status status);
+  static void tx_callback(bt_conn *conn);
+  static void rx_callback(bt_conn *conn, const uint8_t *data, uint16_t len);
+  static void connected(bt_conn *conn, uint8_t err);
+  static void disconnected(bt_conn *conn, uint8_t reason);
+
+  std::atomic<bt_conn *> conn_ = nullptr;
+  bool expose_log_ = false;
+  atomic_t tx_status_ = ATOMIC_INIT(TX_DISABLED);
+};
+
+}  // namespace esphome::ble_nus
+#endif

esphome/components/bluetooth_proxy/bluetooth_connection.cpp

@@ -230,8 +230,8 @@ void BluetoothConnection::send_service_for_discovery_() {
     service_resp.handle = service_result.start_handle;
 
     if (total_char_count > 0) {
-      // Reserve space and process characteristics
-      service_resp.characteristics.reserve(total_char_count);
+      // Initialize FixedVector with exact count and process characteristics
+      service_resp.characteristics.init(total_char_count);
       uint16_t char_offset = 0;
       esp_gattc_char_elem_t char_result;
       while (true) {  // characteristics
@@ -253,9 +253,7 @@ void BluetoothConnection::send_service_for_discovery_() {
 
         service_resp.characteristics.emplace_back();
         auto &characteristic_resp = service_resp.characteristics.back();
-
         fill_gatt_uuid(characteristic_resp.uuid, characteristic_resp.short_uuid, char_result.uuid, use_efficient_uuids);
-
         characteristic_resp.handle = char_result.char_handle;
         characteristic_resp.properties = char_result.properties;
         char_offset++;
@@ -271,12 +269,11 @@ void BluetoothConnection::send_service_for_discovery_() {
           return;
         }
         if (total_desc_count == 0) {
-          // No descriptors, continue to next characteristic
           continue;
         }
 
-        // Reserve space and process descriptors
-        characteristic_resp.descriptors.reserve(total_desc_count);
+        // Initialize FixedVector with exact count and process descriptors
+        characteristic_resp.descriptors.init(total_desc_count);
         uint16_t desc_offset = 0;
         esp_gattc_descr_elem_t desc_result;
         while (true) {  // descriptors
@@ -297,9 +294,7 @@ void BluetoothConnection::send_service_for_discovery_() {
 
           characteristic_resp.descriptors.emplace_back();
           auto &descriptor_resp = characteristic_resp.descriptors.back();
-
           fill_gatt_uuid(descriptor_resp.uuid, descriptor_resp.short_uuid, desc_result.uuid, use_efficient_uuids);
-
           descriptor_resp.handle = desc_result.handle;
           desc_offset++;
         }

esphome/components/bluetooth_proxy/bluetooth_proxy.cpp

@@ -155,16 +155,12 @@ esp32_ble_tracker::AdvertisementParserType BluetoothProxy::get_advertisement_par
 BluetoothConnection *BluetoothProxy::get_connection_(uint64_t address, bool reserve) {
   for (uint8_t i = 0; i < this->connection_count_; i++) {
     auto *connection = this->connections_[i];
-    if (connection->get_address() == address)
+    uint64_t conn_addr = connection->get_address();
+
+    if (conn_addr == address)
       return connection;
-  }
 
-  if (!reserve)
-    return nullptr;
-
-  for (uint8_t i = 0; i < this->connection_count_; i++) {
-    auto *connection = this->connections_[i];
-    if (connection->get_address() == 0) {
+    if (reserve && conn_addr == 0) {
       connection->send_service_ = INIT_SENDING_SERVICES;
       connection->set_address(address);
       // All connections must start at INIT
@@ -175,7 +171,6 @@ BluetoothConnection *BluetoothProxy::get_connection_(uint64_t address, bool rese
       return connection;
     }
   }
-
   return nullptr;
 }
 

esphome/components/bluetooth_proxy/bluetooth_proxy.h

@@ -16,7 +16,9 @@
 
 #include "bluetooth_connection.h"
 
+#ifndef CONFIG_ESP_HOSTED_ENABLE_BT_BLUEDROID
 #include <esp_bt.h>
+#endif
 #include <esp_bt_device.h>
 
 namespace esphome::bluetooth_proxy {

esphome/components/bme680_bsec/__init__.py

@@ -41,7 +41,7 @@ CONFIG_SCHEMA = cv.All(
     cv.Schema(
         {
             cv.GenerateID(): cv.declare_id(BME680BSECComponent),
-            cv.Optional(CONF_TEMPERATURE_OFFSET, default=0): cv.temperature,
+            cv.Optional(CONF_TEMPERATURE_OFFSET, default=0): cv.temperature_delta,
             cv.Optional(CONF_IAQ_MODE, default="STATIC"): cv.enum(
                 IAQ_MODE_OPTIONS, upper=True
             ),

esphome/components/bme68x_bsec2/__init__.py

@@ -139,7 +139,7 @@ CONFIG_SCHEMA_BASE = (
             cv.Optional(CONF_SUPPLY_VOLTAGE, default="3.3V"): cv.enum(
                 VOLTAGE_OPTIONS, upper=True
             ),
-            cv.Optional(CONF_TEMPERATURE_OFFSET, default=0): cv.temperature,
+            cv.Optional(CONF_TEMPERATURE_OFFSET, default=0): cv.temperature_delta,
             cv.Optional(
                 CONF_STATE_SAVE_INTERVAL, default="6hours"
             ): cv.positive_time_period_minutes,

esphome/components/button/__init__.py

@@ -84,11 +84,6 @@ def button_schema(
     return _BUTTON_SCHEMA.extend(schema)
 
 
-# Remove before 2025.11.0
-BUTTON_SCHEMA = button_schema(Button)
-BUTTON_SCHEMA.add_extra(cv.deprecated_schema_constant("button"))
-
-
 async def setup_button_core_(var, config):
     await setup_entity(var, config, "button")
 

esphome/components/button/automation.h

@@ -11,7 +11,7 @@ template<typename... Ts> class PressAction : public Action<Ts...> {
  public:
   explicit PressAction(Button *button) : button_(button) {}
 
-  void play(Ts... x) override { this->button_->press(); }
+  void play(const Ts &...x) override { this->button_->press(); }
 
  protected:
   Button *button_;

esphome/components/canbus/canbus.h

@@ -105,9 +105,9 @@ class Canbus : public Component {
   CallbackManager<void(uint32_t can_id, bool extended_id, bool rtr, const std::vector<uint8_t> &data)>
       callback_manager_{};
 
-  virtual bool setup_internal();
-  virtual Error send_message(struct CanFrame *frame);
-  virtual Error read_message(struct CanFrame *frame);
+  virtual bool setup_internal() = 0;
+  virtual Error send_message(struct CanFrame *frame) = 0;
+  virtual Error read_message(struct CanFrame *frame) = 0;
 };
 
 template<typename... Ts> class CanbusSendAction : public Action<Ts...>, public Parented<Canbus> {
@@ -129,7 +129,7 @@ template<typename... Ts> class CanbusSendAction : public Action<Ts...>, public P
     this->remote_transmission_request_ = remote_transmission_request;
   }
 
-  void play(Ts... x) override {
+  void play(const Ts &...x) override {
     auto can_id = this->can_id_.has_value() ? *this->can_id_ : this->parent_->can_id_;
     auto use_extended_id =
         this->use_extended_id_.has_value() ? *this->use_extended_id_ : this->parent_->use_extended_id_;