ai-rules-sync

agentsync

One source of truth for your AI coding-agent rules.

🔗 Live playground: https://panishandsome.github.io/ai-rules-sync/

Codex reads AGENTS.md. Claude Code reads CLAUDE.md. Cursor reads .cursorrules.
Copilot reads .github/copilot-instructions.md. Keeping them in sync by hand is
tedious and they drift. agentsync converts between all of them — or
generates a clean AGENTS.md from a short spec.

Zero dependencies. The exact same engine (src/core/agentsync.js) powers both the
CLI and the browser playground.

Install

Or just clone and run from source — there are no dependencies:

Set it up in one command

That's the lazy path. In your repo it: generates AGENTS.md (by scanning the
project), writes an agentsync.json, runs the first sync, and installs a git
pre-commit hook so every commit keeps the files in sync. From then on you just
edit AGENTS.md and commit. Use agentsync setup --auto to let the hook accept
edits to *any* rule file, or --no-hook to skip the hook.

Quick start (manual)

Keep one source of truth, sync the rest

Write AGENTS.md once and let the other tools' files be generated from it. Create
the config (it auto-detects which rule files you already have):

Make it automatic with a pre-commit hook (so the committed files are always in sync):

Edit only AGENTS.md from then on — the other files are generated outputs.

Don't want to be tied to one file? Use --auto

With --auto you can edit whichever file your current tool prefers (CLAUDE.md in
Claude Code, .cursorrules in Cursor, AGENTS.md in Codex…). agentsync tracks a
snapshot in .agentsync-state.json, figures out which file you changed, and
regenerates the rest from it:

If you edited two files since the last sync, it stops and asks which one wins:

Hook it up the same way: echo "npx agentsync sync…