diff --git a/esphome/components/api/api_frame_helper_noise.cpp b/esphome/components/api/api_frame_helper_noise.cpp
index e952ea670b..633b07a7fa 100644
--- a/esphome/components/api/api_frame_helper_noise.cpp
+++ b/esphome/components/api/api_frame_helper_noise.cpp
@@ -434,8 +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());
diff --git a/esphome/components/api/api_frame_helper_plaintext.cpp b/esphome/components/api/api_frame_helper_plaintext.cpp
index 471e6c5404..dcbd35aa32 100644
--- a/esphome/components/api/api_frame_helper_plaintext.cpp
+++ b/esphome/components/api/api_frame_helper_plaintext.cpp
@@ -230,8 +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());
diff --git a/esphome/core/application.cpp b/esphome/core/application.cpp
index c745aa0ae5..61cfcc7585 100644
--- a/esphome/core/application.cpp
+++ b/esphome/core/application.cpp
@@ -576,10 +576,11 @@ void Application::yield_with_select_(uint32_t delay_ms) {
     // Update fd_set if socket list has changed
     if (this->socket_fds_changed_) {
       FD_ZERO(&this->base_read_fds_);
+      // fd bounds are already validated in register_socket_fd() or guaranteed by platform design:
+      // - ESP32: LwIP guarantees fd < FD_SETSIZE by design (LWIP_SOCKET_OFFSET = FD_SETSIZE - CONFIG_LWIP_MAX_SOCKETS)
+      // - Other platforms: register_socket_fd() validates fd < FD_SETSIZE
       for (int fd : this->socket_fds_) {
-        if (fd >= 0 && fd < FD_SETSIZE) {
-          FD_SET(fd, &this->base_read_fds_);
-        }
+        FD_SET(fd, &this->base_read_fds_);
       }
       this->socket_fds_changed_ = false;
     }