diff --git a/CLAUDE.md b/CLAUDE.md
index c267348a..a5a38694 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -130,6 +130,7 @@ Never duplicate logic across handlers or services. If the same behaviour is need
 - Naming: `camelCase` for variables/functions, `PascalCase` for classes
 - No `var` — use `const`/`let` only
 - **JSDoc required** on all public functions — `jsconfig.json` enables `checkJs` globally (equivalent to `@ts-check` on every file)
+- Always us static/js/core/types.js to mapp OxCcloud API structure
 - Type parameters, return types, and complex types via `@typedef`:
 
 ```js
@@ -162,6 +163,17 @@ Never duplicate logic across JS modules. If the same behaviour is needed in more
 - One CSS file per logical component in `/static/css/`
 - [data-theme="dark"] is permitted only in /static/css/themes/dark.css
 
+## Frontend Pre-commit checks
+
+Always run these before committing, in this order:
+
+```bash
+biome check --fix                                           # Auto-format
+biome lint  --fix                                           # Lint (must pass)
+stylelint static/css/                                       # Css rules
+tsc -p jsconfig.json --noEmit                               # Ensure JS is always typed
+```
+
 # What Claude must NOT do
 - Edit `Cargo.lock` directly
 - Use npm dependencies not listed in this file