如何將 CLAUDE.md 控制在 40 行內，讓 Claude Code 更易遵循規則

Most CLAUDE.md files I see grow into a wiki: architecture notes, style essays, a changelog, three pasted READMEs. Then people wonder why the agent ignores the one rule that mattered.

CLAUDE.md is loaded into context at the start of a session, so every line competes with your actual task. Short, concrete house rules beat long explanations.

A shape that works

# House rules

## Before you edit
- Read the file and its tests before changing it.
- Ask before adding a new dependency.

## Commands
- Test: `npm test`
- Lint: `npm run lint -- --fix`
- Never run: `git push --force`, `rm -rf`, database migrations.

## Done means
- Tests and lint pass locally.
- You list the files you changed and why, in one line each.

## Style
- Match the surrounding code. No drive-by refactors.

That is the whole file. Each line is something you could check in a diff.

Rules of thumb

• Commands over prose. "Test: npm test" is better than a paragraph about the test philosophy.
• Enforce, don't plead. If a rule really must hold (no force-push, tests after edits), put it in a hook or the allow-list in settings.json. CLAUDE.md is guidance; hooks are guarantees.
• Move reference material out. Link to docs/architecture.md and let the agent read it when needed instead of loading it every session.
• Prune monthly. If a rule never changed a diff, delete it.

Check the memory docs for your installed Claude Code version; how nested and user-level files are loaded can change between releases.

I ship this short house-rules file together with the allow-list and the safety hooks in Vildanden Agent Config. The free sample is enough to try the pattern today.