What is a CLAUDE.md file?
AI coding assistants read a plain Markdown file in your repository before they start work. Claude Code reads CLAUDE.md, Codex and many other agents read AGENTS.md, Cursor reads rules in .cursor/rules/, and GitHub Copilot reads .github/copilot-instructions.md. A good file tells the assistant what the project is, how to run and test it, and the house rules — so you stop repeating yourself in every chat and get code that fits your project the first time.
How to use the generator
- Fill in the form. Every file updates as you type.
- Pick a file tab, then copy it or download it.
- Save it at the path shown, in the root of your repository, and commit it so your whole team shares it.
Tips for good AI rules
- Keep it short and specific. “Run
npm testbefore finishing” beats “write good code”. - Put the exact commands in. Assistants use them to check their own work.
- Add a rule each time the assistant makes the same mistake twice.
.mcp.jsonlists MCP servers that give an assistant extra tools; only add servers you trust.