Merge pull request #11862 from esphome/bump-2025.11.0b1

2025.11.0b1

.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:**
@@ -100,8 +172,7 @@ This document provides essential context for AI models interacting with this pro
 
     *   **C++ Class Pattern:**
         ```cpp
-        namespace esphome {
-        namespace my_component {
+        namespace esphome::my_component {
 
         class MyComponent : public Component {
          public:
@@ -117,8 +188,7 @@ This document provides essential context for AI models interacting with this pro
           int param_{0};
         };
 
-        }  // namespace my_component
-        }  // namespace esphome
+        }  // namespace esphome::my_component
         ```
 
     *   **Common Component Examples:**
@@ -221,6 +291,146 @@ 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.
 
@@ -228,3 +438,45 @@ 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 @@
-049d60eed541730efaa4c0dc5d337b4287bf29b6daa350b5dfc1f23915f1c52f
+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-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/codeowner-review-request.yml

@@ -21,7 +21,7 @@ permissions:
 jobs:
   request-codeowner-reviews:
     name: Run
-    if: ${{ !github.event.pull_request.draft }}
+    if: ${{ github.repository == 'esphome/esphome' && !github.event.pull_request.draft }}
     runs-on: ubuntu-latest
     steps:
       - name: Request reviews from component codeowners

.github/workflows/codeql.yml

@@ -58,7 +58,7 @@ jobs:
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@e296a935590eb16afc0c0108289f68c87e2a89a5 # v4.30.7
+        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@e296a935590eb16afc0c0108289f68c87e2a89a5 # v4.30.7
+        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: v0.14.0
+    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
@@ -153,12 +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
@@ -177,7 +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
@@ -198,9 +202,11 @@ 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
+esphome/components/hlk_fm22x/* @OnFreund
 esphome/components/hm3301/* @freekode
 esphome/components/hmac_md5/* @dwmw2
 esphome/components/homeassistant/* @esphome/core @OttoWinter
@@ -285,6 +291,7 @@ 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
@@ -389,6 +396,7 @@ esphome/components/rpi_dpi_rgb/* @clydebarrow
 esphome/components/rtl87xx/* @kuba2k2
 esphome/components/rtttl/* @glmnet
 esphome/components/runtime_stats/* @bdraco
+esphome/components/rx8130/* @beormund
 esphome/components/safe_mode/* @jsuanet @kbx81 @paulmonigatti
 esphome/components/scd4x/* @martgras @sjtrny
 esphome/components/script/* @esphome/core
@@ -475,6 +483,7 @@ 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         = 2025.10.5
+PROJECT_NUMBER         = 2025.11.0b1
 
 # 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

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
@@ -173,14 +207,14 @@ 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)
@@ -284,7 +318,17 @@ def has_resolvable_address() -> bool:
     """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
-    return CORE.address is not None
+    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):
@@ -468,7 +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
@@ -890,6 +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:
@@ -1005,6 +1099,7 @@ POST_CONFIG_ACTIONS = {
     "idedata": command_idedata,
     "rename": command_rename,
     "discover": command_discover,
+    "analyze-memory": command_analyze_memory,
 }
 
 SIMPLE_CONFIG_ACTIONS = [
@@ -1290,6 +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>.
     #

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.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

@@ -71,10 +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"
@@ -155,6 +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(
         {
@@ -214,6 +227,7 @@ CONFIG_SCHEMA = cv.All(
                 esp32=8,  # More RAM, can buffer more
                 rp2040=5,  # Limited RAM
                 bk72xx=8,  # Moderate RAM
+                nrf52=8,  # Moderate RAM
                 rtl87xx=8,  # Moderate RAM
                 host=16,  # Abundant resources
                 ln882x=8,  # Moderate RAM
@@ -222,6 +236,7 @@ CONFIG_SCHEMA = cv.All(
     ).extend(cv.COMPONENT_SCHEMA),
     cv.rename_key(CONF_SERVICES, CONF_ACTIONS),
     _validate_api_config,
+    _consume_api_sockets,
 )
 
 
@@ -230,6 +245,9 @@ 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")
@@ -246,6 +264,10 @@ 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")
 
@@ -253,6 +275,8 @@ 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 = []
@@ -266,8 +290,10 @@ 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")
@@ -380,12 +406,19 @@ async def homeassistant_service_to_code(
     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))
@@ -458,15 +491,23 @@ 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
 
 
@@ -489,6 +530,8 @@ 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];
@@ -776,9 +776,9 @@ 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"];
@@ -866,7 +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";
@@ -876,10 +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;
@@ -888,7 +888,7 @@ message ExecuteServiceRequest {
   option (ifdef) = "USE_API_SERVICES";
 
   fixed32 key = 1;
-  repeated ExecuteServiceArgument args = 2;
+  repeated ExecuteServiceArgument args = 2 [(fixed_vector) = true];
 }
 
 // ==================== CAMERA ====================
@@ -987,9 +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;
@@ -997,21 +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;
@@ -1142,7 +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"];
@@ -1519,7 +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.
@@ -1531,7 +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.
@@ -2146,7 +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

@@ -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()));
@@ -1465,6 +1467,8 @@ bool APIConnection::send_device_info_response(const DeviceInfoRequest &msg) {
   static constexpr auto MANUFACTURER = StringRef::from_lit("Beken");
 #elif defined(USE_LN882X)
   static constexpr auto MANUFACTURER = StringRef::from_lit("Lightning");
+#elif defined(USE_NRF52)
+  static constexpr auto MANUFACTURER = StringRef::from_lit("Nordic Semiconductor");
 #elif defined(USE_RTL87XX)
   static constexpr auto MANUFACTURER = StringRef::from_lit("Realtek");
 #elif defined(USE_HOST)
@@ -1569,7 +1573,13 @@ bool APIConnection::send_noise_encryption_set_key_response(const NoiseEncryption
   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_frame_helper_noise.cpp

@@ -242,7 +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
@@ -250,17 +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;
 
@@ -339,32 +338,32 @@ 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) {
@@ -435,8 +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_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());

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
@@ -1064,6 +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:
@@ -1085,6 +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 {
@@ -1163,14 +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
@@ -1185,6 +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());
@@ -1212,8 +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()) {
@@ -1222,8 +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);
@@ -1239,6 +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);
@@ -1457,8 +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));
@@ -1474,8 +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);
@@ -2859,8 +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);
@@ -2876,9 +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{};
@@ -1110,9 +1110,9 @@ class HomeassistantActionRequest final : public ProtoMessage {
 #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};
@@ -1263,7 +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
@@ -1279,10 +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
@@ -1300,7 +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
@@ -1369,27 +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
@@ -1531,7 +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
@@ -1923,7 +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;
@@ -1937,7 +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;
@@ -2785,7 +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));
@@ -1292,6 +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");
@@ -2046,7 +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_server.cpp

@@ -5,6 +5,7 @@
 #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"
@@ -34,7 +35,7 @@ APIServer::APIServer() {
 }
 
 void APIServer::setup() {
-  this->setup_controller();
+  ControllerRegistry::register_controller(this);
 
 #ifdef USE_API_NOISE
   uint32_t hash = 88491486UL;
@@ -224,7 +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()) {
@@ -269,7 +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()) \
@@ -278,15 +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
@@ -304,15 +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
@@ -320,7 +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
@@ -336,11 +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
@@ -356,12 +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
 
@@ -468,6 +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
@@ -482,27 +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

@@ -53,6 +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
@@ -71,19 +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;
@@ -95,10 +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;
@@ -124,8 +125,14 @@ class APIServer : public Component, public Controller {
 #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
@@ -134,7 +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;
@@ -174,6 +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
@@ -226,7 +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

@@ -41,10 +41,14 @@ 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;
 };
@@ -93,15 +97,22 @@ template<typename... Ts> class HomeAssistantServiceCallAction : public Action<Ts
 
   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));
   }
 
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES
@@ -122,29 +133,14 @@ template<typename... Ts> class HomeAssistantServiceCallAction : public Action<Ts
   Trigger<std::string, Ts...> *get_error_trigger() const { return this->error_trigger_; }
 #endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
 
-  void play(Ts... x) override {
+  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->flags_.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...);
-    }
+    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) {
@@ -189,11 +185,28 @@ template<typename... Ts> class HomeAssistantServiceCallAction : public Action<Ts
   }
 
  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_;
   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_{""};

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>()...};
+    msg.args.init(sizeof...(Ts));
     for (size_t i = 0; i < sizeof...(Ts); i++) {
-      msg.args.emplace_back();
-      auto &arg = msg.args.back();
+      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);