Google Calendar MCP Server (Python)

What is Google Calendar MCP Server (Python)?

A Python-based MCP (Model Context Protocol) server that acts as an interface between Large Language Models and the Google Calendar API. It enables LLMs to perform calendar operations via natural language requests. Secure OAuth 2.0 authentication is built in. For users who want to manage Google Calendar through AI assistants.

How to use Google Calendar MCP Server (Python)?

Requires Python 3.8+, Git, a Google Cloud project with the Calendar API enabled, and OAuth 2.0 Desktop app credentials. Set up a .env file with your Client ID, Client Secret, token file path, and optionally the callback port. Install dependencies with pip install -r requirements.txt. Run python run_server.py once for initial OAuth authentication; after that, the MCP client launches the server automatically. Configure your MCP client (e.g., Cursor/Claude Desktop) via an mcp.json entry that provides the full absolute path to run_server.py as the command argument.

Key features of Google Calendar MCP Server (Python)

• Secure Google Calendar API access via OAuth 2.0 with automatic token storage/refresh.
• List, create, update, and delete calendars.
• Find events with basic and advanced filtering.
• Create detailed events and quick-add events from text.
• Add and check attendee response status.
• Query free/busy information for multiple calendars.
• Schedule mutual free slots automatically and analyze daily busyness.

Use cases of Google Calendar MCP Server (Python)

• Schedule meetings by asking an LLM to find free slots across multiple calendars.
• Check attendee availability and response status without manual calendar browsing.
• Add or update events, delete events, and manage attendees via natural language.
• Analyze daily event counts and durations to optimize your schedule.
• Quickly add events from plain text descriptions (e.g., “Lunch with John tomorrow at noon”).

FAQ from Google Calendar MCP Server (Python)

What authentication method does the server use?

It uses the Google OAuth 2.0 Desktop App flow. The server automatically stores and refreshes tokens after the first authorization.

How do I configure my MCP client to use this server?

After initial authentication, add a JSON entry to your client’s settings (e.g., mcp.json). Set command to the full path of your Python executable and args to the full absolute path of run_server.py. Credentials remain in the .env file, not in the client config.

Where are my credentials and tokens stored?

Your Google Client ID and Client Secret are stored in the .env file in the project root. OAuth tokens are saved to the file specified by TOKEN_FILE_PATH (default .gcp-saved-tokens.json). Both files should be kept secure and are typically added to .gitignore.

What Google Calendar permissions does the server need?

By default, the server requests read/write access to the Calendar API (https://www.googleapis.com/auth/calendar). You can set CALENDAR_SCOPES to read-only if needed.

Can I test the server without an MCP client?

Yes. After the initial authentication, running python run_server.py starts a FastAPI server (e.g., on http://localhost:8000) that you can test with tools like curl or Postman. For routine use, the MCP client handles launching.