Agents Sync — one source of truth for your AI coding rules

Stop copy-pasting the same project instructions into CLAUDE.md, .cursor/rules, and .github/copilot-instructions.md. Agents Sync keeps them all generated from a single AGENTS.md — the open standard adopted by 60,000+ repositories — and warns you the moment they drift apart.

Why

If you use more than one AI coding tool (Claude Code, Cursor, GitHub Copilot, Windsurf…), each one wants its own instruction file. Keeping them consistent by hand means either endless copy-paste or silent drift, where each tool follows different rules.

Agents Sync treats AGENTS.md as the single source of truth:

• ✅ Save & sync — edit AGENTS.md, and every target file updates instantly
• ⚠️ Drift detection — if a generated file is edited directly, the status bar warns you and offers a one-click fix
• 📥 Adopt — already have a CLAUDE.md or .cursorrules? Generate your AGENTS.md from it in one command
• 🩺 Freshness check — flags file paths referenced in AGENTS.md that no longer exist, right in the Problems panel
• 🔢 Token budget meter — estimates the combined token cost of AGENTS.md and its generated targets in the status bar, and warns once it crosses your budget
• 🛡️ Safe by default — files that Agents Sync didn't generate are never overwritten without your explicit confirmation
• 🔒 Fully local — no network calls, no LLM API, no telemetry. Your rules never leave your machine

Supported targets

Each target can be toggled in settings. Generated files carry a header marking them as generated — edit AGENTS.md instead.

Commands

• Agents Sync: Sync Now — regenerate all enabled targets from AGENTS.md
• Agents Sync: Adopt Existing Instructions — create AGENTS.md from your existing CLAUDE.md / .github/copilot-instructions.md / .cursorrules

Settings

• agentsSync.targets — which targets to generate (default: ["claude", "cursor", "copilot"]; also available: windsurf, cline, gemini, aider)
• agentsSync.autoSync — sync automatically when AGENTS.md is saved (default: true)
• agentsSync.freshnessCheck — warn about referenced file paths that no longer exist (default: true)
• agentsSync.tokenBudget.warnAt — token estimate threshold before the status bar warns (default: 8000)

Status bar

• ✓ Agents Sync — everything in sync
• ⚠ Agents Sync — drift detected; click to overwrite from AGENTS.md, open a diff, or ignore

Known limitations (MVP)

• Multi-root workspaces: only the first folder is handled
• Sync is one-way (AGENTS.md → targets); reverse import is on the roadmap

Privacy

Agents Sync runs entirely on your machine. It reads and writes files only inside your workspace. As of v0.2.1 it makes zero network requests and collects no data of any kind — and since it's open source under MIT, you can verify that yourself.

Tip: as with any tool that writes files, we recommend using it in a version-controlled (git) workspace.

Agents Sync is an independent project. It is not affiliated with or endorsed by Anthropic, Microsoft, GitHub, Anysphere (Cursor), Google, or Cognition (Windsurf); product names are used only to describe compatibility.

Development notes for contributors live in docs/dev-notes.md.