Write the project's rules in AGENTS.md
Draft AGENTS.md with /init, trim it to the rules that matter and test it in a fresh chat.
New to Codex? Start with the first lesson in this guide.
What this lesson covers
- Notice what you keep repeating
- Draft it with /init
- Trim it to rules that matter
- Test it in a fresh chat
- Know what rules can't do
You’ll come away with: Write the project's rules once in a short AGENTS.md, test them in a fresh chat, and remember that rules guide Codex while the sandbox enforces limits.