Cirby 🩷

Merge AI coding agent configs into the unified AGENTS.md standard.

Cirby = Code + Kirby — absorbs all your agent configs and unifies them into one.

The Problem

Different AI coding agents use different configuration files:

Agent	Config File
Claude Code	CLAUDE.md
Cursor	.cursorrules, .cursor/rules/*.mdc
Windsurf	.windsurfrules
GitHub Copilot	.github/copilot-instructions.md
Codex	CODEX.md
OpenCode, AMP	AGENTS.md ✓

This creates friction when your team uses different tools, and makes it hard to maintain consistent instructions across agents.

The Solution

cirby scans your project, merges all agent configs into AGENTS.md, and creates symlinks so each tool still finds its expected file.

$ cirby
Scanning for agent configuration files...
  ✓ CLAUDE.md (Claude Code)
  ✓ .cursorrules (Cursor)
  ✓ .windsurfrules (Windsurf)

✓ Created/updated AGENTS.md
✓ Symlinked CLAUDE.md → AGENTS.md
✓ Symlinked .cursorrules → AGENTS.md
✓ Symlinked .windsurfrules → AGENTS.md

🎉 Done!

Installation

Go Install

go install github.com/BlackKingBarOrg/cirby@latest

From Source

git clone https://github.com/BlackKingBarOrg/cirby.git
cd cirby
go build -o cirby .

Download Binary

Check the Releases page for pre-built binaries.

Usage

# Merge configs and create symlinks
cirby

# Preview changes without modifying files
cirby --dry-run

# Skip git uncommitted changes check
cirby --force

# Verbose output
cirby --verbose

Safety Features

Git Protection

Cirby requires agent config files to be committed before merging. This ensures you can always rollback via git:

$ cirby
Error: uncommitted changes detected in agent config files:
  - CLAUDE.md (modified)
  - .cursorrules (untracked)

Please commit first so you can rollback if needed:
  git add CLAUDE.md .cursorrules
  git commit -m "backup before cirby"

Use --force to skip this check (not recommended).

Idempotency

Running cirby multiple times is safe. It detects existing symlinks and unchanged content, only updating when necessary.

How It Works

1. Scan — Find all agent config files in your project
2. Merge — Combine content into AGENTS.md (with deduplication)
3. Symlink — Replace original files with symlinks to AGENTS.md

After running cirby:

project/
├── AGENTS.md           ← The source of truth
├── CLAUDE.md           → symlink to AGENTS.md
├── .cursorrules        → symlink to AGENTS.md
├── .windsurfrules      → symlink to AGENTS.md
└── .github/
    └── copilot-instructions.md → symlink to ../AGENTS.md

Contributing

Issues and PRs welcome! This project uses the AGENTS.md standard (of course).

License

MIT

Credits

Named after Kirby, the Nintendo character who absorbs abilities from others. Cirby absorbs your agent configs and unifies them. 🩷