diff --git a/CLAUDE.md b/CLAUDE.md
index 01b8e99..d2daba9 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -7,6 +7,7 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 - **NEVER build, test, or run anything locally.** Always use Docker for all build/test/run operations.
 - **`websitebox-brief (2).md` is the source of truth** for all project decisions and specifications. Always defer to it.
 - **Do not load `websitebox-diagram (1).jsx`** unless the user explicitly asks for it — it is reference material only.
+- **Keep `guide.md` in sync.** Any change that alters the user-facing flow — new commands, renamed scripts, changed setup wizard prompts, added/removed steps, new dependencies, modified ports, updated troubleshooting — **must** also be reflected in `guide.md`. This is a beginner-facing deployment guide in ProjectPublic markup format. If you're unsure whether a change affects the guide, check. Treat guide.md as a living document that must always match the actual codebase.
 
 ## Project Overview