Write a CLAUDE.md Starter for a Repo
CLAUDE.md is the file Claude Code reads at the start of every session. This prompt drafts one from a few facts about your project, kept short and specific.
Works with Claude, ChatGPT and Gemini4 fieldsSaves as CLAUDE.md
Write a CLAUDE.md file for this repository. It is read by Claude Code at the start of every session, so keep it under 60 lines, specific and imperative. Project: A FastAPI service with a React frontend Commands: uv sync; uv run pytest; npm run dev (in web/) Rules: never edit migrations by hand; use the existing logger; ask before adding dependencies Folder layout: api/ backend, web/ frontend, migrations/ alembic Use these sections: Overview, Commands, Code style, Rules, Where things live. Only include facts from what I gave you; mark anything you are unsure about with TODO instead of guessing.
Everything you type stays in your browser. Remove passwords, keys and personal data before pasting anything into an AI tool.
Why this prompt is written this way
- Short and imperative. Instructions files work best when every line is a rule the agent can act on.
- TODO instead of guessing. A wrong fact in CLAUDE.md is repeated in every session, so gaps are marked, not invented.
- Fixed sections. A predictable layout makes the file easy to update later.
Example answer
Illustrative and shortened, to show the shape of a good answer. Real answers vary by model.
# Overview FastAPI service (api/) with a React frontend (web/). # Commands - Install: uv sync - Test: uv run pytest # Rules - Never edit files in migrations/ by hand. - Ask before adding a dependency.
Tips
- Read the CLAUDE.md guide for where the file lives and how imports work.
- Update the file whenever you correct the agent twice for the same thing.
How to use it
- Replace the example values with your own. The prompt on the right updates as you type.
- Press Copy prompt and paste it into any AI chat, or open it straight in Claude or ChatGPT.
- Save it as CLAUDE.md if you want to reuse it or keep it in your repository.