Cal.com MCP Server
Exposes Cal.com scheduling tools to AI agents via the Model Context Protocol (MCP).
Tools Available
| Tool | Description | |------|-------------| | list_event_types | List all available event types (meeting types) | | get_availability | Get free/busy slots for a date range | | create_booking | Create a new booking/appointment | | cancel_booking | Cancel an existing booking | | reschedule_booking | Move a booking to a new time slot | | list_bookings | List bookings with status filters |
Setup
1. Configure environment
cp .env.example .env
# Edit .env and set your CAL_API_KEY2. Install dependencies
npm install3. Run tests
npm test4. Start the server
npm start
# Server will run at http://localhost:3000Transport Options
Streamable HTTP (recommended for production)
POST http://localhost:3000/mcp
GET http://localhost:3000/mcpSSE (Server-Sent Events)
GET http://localhost:3000/sse # Open SSE stream
POST http://localhost:3000/sse-messages # Send messagesstdio (local testing)
TRANSPORT=stdio npm startConnecting to Claude
Add to your MCP client config: ``json { "mcpServers": { "calcom": { "url": "http://localhost:3000/mcp", "transport": "streamable-http" } } } ``
API Endpoints
GET /health— Health checkGET /— Server manifest (lists tools and capabilities)POST /mcp— MCP Streamable HTTP endpointGET /sse— SSE connectionPOST /sse-messages— SSE message endpoint
Environment Variables
| Variable | Description | Default | |----------|-------------|---------| | CAL_API_KEY | Cal.com API key (required) | — | | CAL_API_BASE | Cal.com API base URL | https://api.cal.com/v1 | | PORT | HTTP server port | 3000 | | TRANSPORT | http or stdio | http | | LOG_LEVEL | debug, info, warn, error | info |
