From 4d683d5a69d0f3e54e0a5a827c9a6b2e02cc4cb1 Mon Sep 17 00:00:00 2001
From: Jesse Hills <3060199+jesserockz@users.noreply.github.com>
Date: Mon, 4 Aug 2025 14:45:35 +1200
Subject: [PATCH] [AI] Add note about the defines.h file needing to include all
 new defines added (#10054)

---
 .ai/instructions.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/.ai/instructions.md b/.ai/instructions.md
index 6504c7370d..6c002f9617 100644
--- a/.ai/instructions.md
+++ b/.ai/instructions.md
@@ -168,6 +168,8 @@ This document provides essential context for AI models interacting with this pro
     *   `platformio.ini`: Configures the PlatformIO build environments for different microcontrollers.
     *   `.pre-commit-config.yaml`: Configures the pre-commit hooks for linting and formatting.
 *   **CI/CD Pipeline:** Defined in `.github/workflows`.
+*   **Static Analysis & Development:**
+    *   `esphome/core/defines.h`: A comprehensive header file containing all `#define` directives that can be added by components using `cg.add_define()` in Python. This file is used exclusively for development, static analysis tools, and CI testing - it is not used during runtime compilation. When developing components that add new defines, they must be added to this file to ensure proper IDE support and static analysis coverage. The file includes feature flags, build configurations, and platform-specific defines that help static analyzers understand the complete codebase without needing to compile for specific platforms.
 
 ## 6. Development & Testing Workflow