Provides tools to list upcoming events, create events (optionally recurring), and update existing events in a Google Calendar, authenticated via a service account.
Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type @ followed by the MCP server name and your instructions, e.g., "@google-calendar-mcp-serviceaccount List my calendar events for the next 3 days"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
A minimal MCP server that gives an AI agent read/write access to one Google Calendar, authenticated as a service account instead of through interactive OAuth.
Most Google Calendar MCP servers use OAuth: the app asks a human to sign in and grant consent, the way a real multi-user product would. For a personal assistant that only ever needs access to your own calendar, that's more ceremony than the job requires — publishing to production, verified domains, periodic re-consent.
A service account skips all of it: you share your calendar with the service account's email address, exactly like sharing it with another person. The credential doesn't expire until you revoke it.
Trade-off: it only works for calendars you can explicitly share by email (personal Google accounts, most Workspace setups) — it can't act broadly across a user's account the way a full OAuth grant can.
Cost: as of this writing, everything in the setup below is free — no billing account or credit card needs to be attached to the Google Cloud project. The Calendar API's free quota is far beyond what a personal assistant will ever use. This could change in the future; check current Google Cloud pricing if in doubt.
Related MCP server: Google Calendar MCP Server
Tool | Purpose |
| List upcoming events in the next N days |
| Create an event, optionally recurring (RRULE) |
| Update an existing event's summary or time |
No delete_event on purpose — add it yourself if you want an agent able to
delete calendar entries.
Setting this up with the help of an AI coding assistant? Point it at AGENTS.md — it has the full step-by-step for both the human and the agent side.
Doing it manually:
In Google Cloud Console: create a project, enable the Calendar API, create a service account (not an OAuth client), download its JSON key
Share your Google Calendar with the service account's email address, with "Make changes to events" permission. Note the calendar's ID: for your own primary calendar this is just your email address; for any other calendar, find it under that calendar's Settings → "Integrate calendar" → "Calendar ID"
python3 -m venv venv && ./venv/bin/pip install -r requirements.txt
Copy .env.example to .env and fill in the key path and your calendar ID
Register calendar_server.py with your MCP client as a stdio server,
passing those two variables as its environment
MIT — see LICENSE.
This server cannot be deployed
Calendar API for AI agents: events, availability, Google/Microsoft setup, scheduling, and iCal.
Hosted Google Calendar MCP server for AI agents. No self-hosting or Google Cloud setup.
GDPR-compliant calendar access for AI assistants. Google, Microsoft 365, Apple & more. EU-hosted.
Agent-Native Google Calendar - manage events, sync, and public booking
