How to integrate Google Calendar MCP with Codex

Codex is one of the most popular coding harnesses out there. And MCP makes the experience even better. With Google Calendar MCP integration, you can draft, triage, summarise emails, and much more, all without leaving the terminal or the app, whichever you prefer.

Get started for freeGet a demo
Google Calendar logoGoogle Calendar
Oauth2

Google Calendar is a time management service for scheduling meetings, events, and reminders. It streamlines personal and team organization with integrated notifications and sharing options.

44 Tools7 Triggers

Introduction

Codex is one of the most popular coding harnesses out there. And MCP makes the experience even better. With Google Calendar MCP integration, you can draft, triage, summarise emails, and much more, all without leaving the terminal or the app, whichever you prefer.

Also integrate Google Calendar with

ChatGPTOpenAI Agents SDKClaude Agent SDKClaude CodeClaude CoworkOpenCodeCursorVS CodeOpenClawHermesCLIGoogle ADKLangChainVercel AI SDKMastra AILlamaIndexCrewAI

Why use Composio?

Apart from a managed and hosted MCP server, you will get:

  • CodeAct: A dedicated workbench that allows GPT to write its code to handle complex tool chaining. Reduces to-and-fro with LLMs for frequent tool calling.
  • Large tool responses: Handle them to minimise context rot.
  • Dynamic just-in-time access to 20,000 tools across 1000+ other Apps for cross-app workflows. It loads the tools you need, so GPTs aren't overwhelmed by tools you don't need.

How to install Google Calendar MCP in Codex

Run the setup command

Run this command in your terminal to add the Composio MCP server to Codex.

Terminal

It will initiate the authentication in a browser window, authorize Codex to access your Composio account.

Composio authentication page

(Optional) Authenticate with OAuth

To authenticate manually, run the login command to open a browser window and authorize Codex to access your Composio account.

bash
codex mcp login composio

Verify the connection

Run codex mcp list to confirm Composio appears as a registered MCP server.

bash
codex mcp list

Codex App

Codex App follows the same approach as VS Code.

  1. Click ⚙️ on the bottom left → MCP Servers → + Add servers → Streamable HTTP:
  2. Fill the header and Key fields with { "x-consumer-api-key" = "ck_*******" }.
  3. The Key is the Composio API key, that you can find on dashboard.composio.dev
  4. Click on Authenticate and authorize Codex to your Composio account and you're all set.
Codex App MCP setup
  1. Restart and verify if it's there in .codex/config.toml
bash
[mcp_servers.composio]
url = "https://connect.composio.dev/mcp"
http_headers = { "x-consumer-api-key" = "ck_*******" }

What is the Google Calendar MCP server, and what's possible with it?

The Google Calendar MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Google Calendar account. It provides structured and secure access to your calendars and events, so your agent can schedule meetings, create or modify events, list upcoming appointments, and manage calendars—all on your behalf.

  • Automated event creation and scheduling: Easily instruct your agent to add new events, meetings, or reminders with specific times, attendees, and details.
  • Event listing and agenda overview: Have your agent list all upcoming, past, or filtered events on any of your calendars to keep you on top of your schedule.
  • Calendar management and customization: Direct your agent to create new calendars, update calendar details, or even insert calendars into your list for better organization.
  • Event updating and deletion: Let your agent modify existing events or remove events that are no longer needed, keeping your calendar up to date.
  • Complete calendar clearing: Ask your agent to clear all events from a primary calendar or delete secondary calendars entirely when you need a fresh start.

Conclusion

You've successfully integrated Google Calendar with Codex using Composio's MCP server. Now you can interact with Google Calendar directly from your terminal, VS Code, or the Codex App using natural language commands.

Key benefits of this setup:

  • Seamless integration across CLI, VS Code, and standalone app
  • Natural language commands for Google Calendar operations
  • Managed authentication through Composio
  • Access to 20,000+ tools across 1000+ apps for cross-app workflows
  • CodeAct workbench for complex tool chaining

Next steps:

  • Try asking Codex to perform various Google Calendar operations
  • Explore cross-app workflows by connecting more toolkits
  • Build automation scripts that leverage Codex's AI capabilities
TOOLS & TRIGGERS

Supported Tools and Triggers

Every Google Calendar action and event your agent gets out of the box.

Delete ACL Rule

Deletes an access control rule from a Google Calendar.

Get ACL Rule

Retrieves a specific access control rule for a calendar.

Create ACL Rule

Creates an access control rule for a calendar.

List ACL Rules

Retrieves the list of access control rules (ACLs) for a specified calendar, providing the necessary 'rule_id' values required for updating specific ACL rules.

Patch ACL Rule

Updates an existing access control rule for a calendar using patch semantics (partial update).

Update ACL Rule

Updates an access control rule for the specified calendar.

Watch ACL Changes

Tool to watch for changes to ACL resources.

Batch Events

Execute up to 1000 event mutations (create/patch/delete) in one Google Calendar HTTP batch request with per-item status/results.

Remove Calendar from List

Tool to remove a calendar from the user's calendar list.

Get Single Calendar by ID

Retrieves metadata for a SINGLE specific calendar from the user's calendar list by its calendar ID.

Insert Calendar into List

Inserts an existing calendar into the user's calendar list, making it visible in the UI.

Patch Calendar List Entry

Updates an existing calendar on the user's calendar list using patch semantics.

Update Calendar List Entry

Updates a calendar list entry's display/subscription settings (color, visibility, reminders, selection) for the authenticated user — does not modify the underlying calendar resource (title, timezone, etc.

Watch Calendar List

Watch for changes to CalendarList resources using push notifications.

Delete Calendar

Deletes a secondary calendar that you own or have delete permissions on.

Update Calendar

Full PUT-style update that overwrites all calendar metadata fields; unspecified optional fields are cleared.

Stop Channel

Tool to stop watching resources through a notification channel.

Clear Calendar

Clears a primary calendar by deleting all events from it.

Get Color Definitions

Returns the color definitions for calendars and events.

Create Event

Create a Google Calendar event using start_datetime plus duration fields.

Delete event

Deletes a specified event by `event_id` from a Google Calendar (`calendar_id`); idempotent — a 404 for an already-deleted event is a no-op.

Create a calendar

Creates a new, empty Google Calendar with the specified title (summary).

Get Event

Retrieves a SINGLE event by its unique event_id (REQUIRED).

Import Event

Tool to import an event as a private copy to a calendar.

Get Event Instances

Returns instances of the specified recurring event.

List Events

Returns events on the specified calendar.

List Events from All Calendars

Return a unified event list across all calendars in the user's calendar list for a given time range.

Move Event

Moves an event to another calendar, i.

Watch Events

Watch for changes to Events resources.

Find event

Finds events in a specified Google Calendar using text query, time ranges (event start/end, last modification), and event types.

Find free slots

Finds both free and busy time slots in Google Calendars for specified calendars within a defined time range.

Get Google Calendar

Retrieves a specific Google Calendar, identified by `calendar_id`, to which the authenticated user has access.

Get current date and time

Gets the current date and time, allowing for a specific timezone offset.

List Buildings

Lists all buildings for a Google Workspace customer account with full details including addresses, coordinates, and floor names.

List Calendar Resources

Retrieves calendar resources (such as conference rooms) from a Google Workspace domain using the Admin SDK Directory API.

List Google Calendars

Retrieves calendars from the user's Google Calendar list, with options for pagination and filtering.

Patch Calendar

Partially updates (PATCHes) an existing Google Calendar, modifying only the fields provided.

Patch Event

Update specified fields of an existing event in a Google Calendar using patch semantics (array fields like `attendees` are fully replaced if provided); ensure the `calendar_id` and `event_id` are valid and the user has write access to the calendar.

Quick Add Event

Parses natural language text to quickly create a basic Google Calendar event with its title, date, and time, suitable for simple scheduling; does not support direct attendee addition or recurring events, and `calendar_id` must be valid if not 'primary'.

Remove attendee from event

Removes an attendee from a specified event in a Google Calendar; the calendar and event must exist.

Get Calendar Setting

Tool to return a single user setting for the authenticated user.

List Settings

Returns all user settings for the authenticated user.

Watch Settings

Watch for changes to Settings resources.

Update Google event

Updates an existing event in Google Calendar.

FRAMEWORKS

How to build Google Calendar MCP Agent with another framework

ChatGPT logo

ChatGPT

Use Google Calendar MCP with ChatGPT

OpenAI Agents SDK logo

OpenAI Agents SDK

Use Google Calendar MCP with OpenAI Agents SDK

Claude Agent SDK logo

Claude Agent SDK

Use Google Calendar MCP with Claude Agent SDK

Claude Code logo

Claude Code

Use Google Calendar MCP with Claude Code

Claude Cowork logo

Claude Cowork

Use Google Calendar MCP with Claude Cowork

Cursor logo

Cursor

Use Google Calendar MCP with Cursor

OpenClaw logo

OpenClaw

Use Google Calendar MCP with OpenClaw

Hermes logo

Hermes

Use Google Calendar MCP with Hermes

CLI logo

CLI

Use Google Calendar MCP with CLI

Google ADK logo

Google ADK

Use Google Calendar MCP with Google ADK

LangChain logo

LangChain

Use Google Calendar MCP with LangChain

Vercel AI SDK logo

Vercel AI SDK

Use Google Calendar MCP with Vercel AI SDK

Mastra AI logo

Mastra AI

Use Google Calendar MCP with Mastra AI

LlamaIndex logo

LlamaIndex

Use Google Calendar MCP with LlamaIndex

CrewAI logo

CrewAI

Use Google Calendar MCP with CrewAI

OpenCode logo

OpenCode

Use Google Calendar MCP with OpenCode

VS Code logo

VS Code

Use Google Calendar MCP with VS Code

FAQ

Frequently asked questions

With a standalone Google Calendar MCP server, the agents and LLMs can only access a fixed set of Google Calendar tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Google Calendar and many other apps based on the task at hand, all through a single MCP endpoint.

Yes, you can. Codex fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Google Calendar tools.

Yes, absolutely. You can configure which Google Calendar scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Google Calendar data and credentials are handled as safely as possible.

Start with Google Calendar.It takes 30 seconds.

Managed auth, hosted MCP servers, and every Google Calendar tool your agent needs.Free to start.

Start building
Customer stories

Teams ship real agents on Composio

GET STARTED FOR FREEBOOK A DEMO
agent.aiZoomLettaGleanHubSpotAWSWabi

Karan skipped his own birthday party to fix our critical issue. It was 10pm and he diverted his Waymo to help us instead. This really sets the bar — it shows the commitment you need when users rely on your software.

Harsha Gaddipati
Harsha Gaddipati
Co-founder, Slashy

A lot of students tell us that the moment their connected tools start talking to each other inside Opennote feels almost magical. The agent just knows them, and it's immensely helped keep new users on the platform.

Abhi Arya
Abhi Arya
Co-founder, Opennote

We chose Composio over Pipedream because it delivered depth where it mattered — niche tools and tricky edge cases other platforms simply ignored. That gave us confidence to scale without compromising.

Nirman Dave
Nirman Dave
CEO, Zams

As a solo builder, shipping fast is life or death. The only way I can outcompete incumbents is by outmanoeuvring them. Getting bogged down managing agent auth would have been a death sentence.

Ryan Yu
Ryan Yu
Founder, Extra Thursday

Before Composio, adding tool integrations was slow and resource-intensive. Each one could take weeks of engineering time, and maintaining them meant constantly keeping up with API changes.

Tomisin Jenrola
Tomisin Jenrola
Founder & CEO, SwarmZero

With hands-on help from their founder, we integrated Gmail and Google Drive in just 30 minutes. This level of personal support and commitment is exactly what startups should strive for.

Jerome Leclanche
Jerome Leclanche
Co-Founder, Ingram Technologies