collabfs-mcp

Real-time collaborative filesystem for AI agents. Two people, two AI agents, one codebase.

What You Get

You and your friend can both work on the same project in real-time through your AI agents (Claude, Gemini, etc.). When your friend edits a file, it instantly appears on your computer. When you edit a file, it instantly appears on theirs.

Installation (10 seconds)

Add this to your AI agent's MCP config:

For Claude Code (~/.config/claude-code/mcp.json):

{
  "mcpServers": {
    "collabfs": {
      "command": "npx",
      "args": ["collabfs-mcp@latest"],
      "env": {
        "COLLABFS_SERVER_URL": "wss://collabfs-server-production.up.railway.app"
      }
    }
  }
}

For other AI agents: Same config, just use their MCP configuration location.

Restart your AI agent.

Usage (2 steps)

You (Host)

Tell your AI agent:

Start CollabFS session on /path/to/your/project

Your AI will respond with a join code like: purple-tiger-2025-11-18-abc123

Share this code with your friend.

Your Friend

Tell their AI agent:

Join CollabFS with code purple-tiger-2025-11-18-abc123
Download all files to /path/where/they/want/files

Done

• You edit files locally - friend sees changes instantly
• Friend tells their AI to edit files - you see changes instantly
• Works with any file type (code, images, PDFs, etc.)
• No manual session ID configuration needed

Example

You:

You: Start CollabFS session on /Users/me/webapp

AI: CollabFS session started!

    JOIN CODE: purple-tiger-2025-11-18-abc123

    Share this code with your friend!

Friend:

Friend: Join CollabFS with code purple-tiger-2025-11-18-abc123
Friend: Download all files to /Users/friend/webapp

AI: Connected! Synced 47 files to /Users/friend/webapp

Result: Both of you are now editing the same codebase through your AI agents in real-time.

Available Commands

Your AI agent has these tools:

• collabfs_host_session - Start a NEW session and get a join code (host only)
• collabfs_connect - Join an EXISTING session with a join code (collaborators)
• collabfs_sync_directory - Load your local files (use watch=true and autoSync=true)
• collabfs_sync_from_crdt - Download all files from session
• collabfs_read_file - Read a specific file
• collabfs_write_file - Write/edit a file
• collabfs_list_files - See all files in session
• collabfs_watch_activity - See what others are doing
• collabfs_disconnect - Leave session

Technical Details

• CRDT-based: Automatic conflict resolution for concurrent edits
• WebSocket sync: Real-time updates with 300ms debouncing
• Binary support: Images, PDFs, fonts, media files work automatically
• Persistence: Server snapshots every 5 minutes
• No setup: Just npx collabfs-mcp@latest - no installation needed

FAQ

Q: Does this work across different AI providers? A: Yes. Claude + Gemini in the same session works perfectly.

Q: How many people can collaborate? A: No hard limit. Tested with 10+ concurrent users.

Q: What happens if two people edit the same line? A: CRDT automatically merges changes. Both edits are preserved.

Q: Is my code stored on the server? A: Yes, session snapshots are stored on the server. Don't use for proprietary code without self-hosting.

Q: Can I self-host? A: Yes. Server code is in the GitHub repository. Deploy anywhere that runs Node.js + Docker.

Q: Does this work offline? A: No. Requires WebSocket connection to server.

Troubleshooting

"Not connected to CollabFS"

• Host: Run collabfs_host_session to start a new session
• Collaborator: Run collabfs_connect with the join code from the host

Changes not syncing Make sure:

• Both users are using the same join code
• Same COLLABFS_SERVER_URL in MCP config
• Host used watch=true and autoSync=true when syncing directory

File not found Run collabfs_list_files to see what's actually in the session.

Advanced: Session Management

Join codes are auto-generated with format: {adjective}-{animal}-{date}-{random}

Examples:

• purple-tiger-2025-11-18-abc123
• golden-dragon-2025-11-18-xyz789

Anyone with the join code can connect to your session. Keep join codes private.

Version

Current: v1.3.0

• Zero-config join codes (no manual session ID setup)
• collabfs_host_session tool for starting sessions
• Human-readable session IDs
• Binary file support
• Automatic bidirectional sync
• File watcher debouncing
• Server-side persistence

See CHANGELOG for full history.

Links

• GitHub: https://github.com/theonlypal/collabfs
• Documentation: https://github.com/theonlypal/collabfs/blob/main/USAGE_GUIDE.md
• Issues: https://github.com/theonlypal/collabfs/issues

License

MIT

Author

Rayan Pal (@theonlypal)