How to integrate Calendarhero MCP with Codex

Trusted by
AWS
Glean
Zoom
Airtable

30 min · no commitment · see it on your stack

Calendarhero logo
Codex logo
divider

Introduction

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

Also integrate Calendarhero with

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 Calendarhero 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 Calendarhero MCP server, and what's possible with it?

The Calendarhero MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Calendarhero account. It provides structured and secure access to your calendar management tools, so your agent can schedule meetings, manage contacts, fetch meeting details, and access your calendar integrations on your behalf.

  • Automated meeting scheduling and requests: Easily have your agent schedule new meetings, select participants, set time ranges, and include extra meeting details in just a few steps.
  • Contact creation and management: Let the agent create new contacts or fetch existing ones, so scheduling is always quick and accurate.
  • Meeting details retrieval: Ask your agent to fetch specific meeting details or get a list of all meetings within a defined timeframe, keeping you up-to-date.
  • Access and manage calendar integrations: Direct your agent to list all connected calendars, add new integrations, or access available calendars for streamlined scheduling.
  • Template and meeting type discovery: Quickly retrieve available meeting templates and types, letting your agent optimize scheduling based on your preferences and routines.

Supported Tools & Triggers

Tools
Add Calendar ConnectionAdd a new calendar directory/connection to the user's CalendarHero account.
Create ContactCreates a new contact in CalendarHero with the provided contact information.
Create Meeting Request V2Tool to create a new meeting request in CalendarHero.
Create WebhookCreates or updates a webhook for a specific event type in CalendarHero.
Delete ContactTool to delete a contact from CalendarHero by its unique identifier.
Delete Meeting TaskTool to delete a meeting task/request from CalendarHero.
Delete Meeting TypeTool to delete a meeting type from the authenticated user's CalendarHero account.
Delete User DirectoryTool to delete a user directory by its UUID.
Delete WebhookTool to delete a webhook subscription for a specific event type.
Fetch ContactFetch Contact
Fetch Meeting DetailsTool to fetch details for meetings within a specified timeframe.
Fetch User ProfileTool to fetch the profile details of the authenticated user.
Get Assistant MessageTool to retrieve a reply message from the CalendarHero assistant.
Get Contact CountTool to get the total count of contacts in CalendarHero.
Get Meeting CategoriesRetrieves the user's meeting categories' stats for a specified time period.
Get Meeting TasksRetrieves the user's meeting requests/tasks from CalendarHero.
Get Search ResultTool to get a search result by ID.
Get User DirectoryTool to retrieve a user's directory by its unique identifier.
Get User OrganizationTool to retrieve the authenticated user's organization details.
Get User SavingsTool to retrieve the authenticated user's savings information from CalendarHero.
Get Webhook ConfigurationTool to get webhook configuration for a specific event type.
Get Webhook SampleTool to retrieve a sample webhook payload for a specific event type.
List Meeting TemplatesRetrieves all meeting templates (reusable meeting configurations) for the authenticated user.
List Meeting TypesRetrieves all meeting types configured for the authenticated CalendarHero user.
List User CalendarsTool to list all calendar integrations connected to a user's CalendarHero account.
List User DirectoriesTool to retrieve all directories configured for a user.
Search ContactTool to search for existing contacts.
Search IntegrationsTool to search across all user integrations for a query term.
Send Assistant MessageTool to send a user's message into the CalendarHero assistant.
Send ReminderSends an email reminder to all contacts/participants about a scheduled meeting request.
Update ContactUpdates an existing contact in CalendarHero with new information.
Update Meeting TypesTool to update meeting type configurations for the authenticated CalendarHero user.
Update Restricted AppsTool to update the authenticated user's restricted apps settings.
Update UserTool to update the authenticated user's profile information.
Update User AddressTool to update the authenticated user's address settings by providing latitude and longitude coordinates.
Update User DirectoryTool to update a user's directory in CalendarHero.
Update User InfoUpdates the authenticated user's info settings in CalendarHero.
Update Work LocationTool to update the user's work location settings in CalendarHero.

Conclusion

You've successfully integrated Calendarhero with Codex using Composio's MCP server. Now you can interact with Calendarhero 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 Calendarhero 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 Calendarhero operations
  • Explore cross-app workflows by connecting more toolkits
  • Build automation scripts that leverage Codex's AI capabilities

How to build Calendarhero MCP Agent with another framework

FAQ

What are the differences in Tool Router MCP and Calendarhero MCP?

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

Can I use Tool Router MCP with Codex?

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 Calendarhero tools.

Can I manage the permissions and scopes for Calendarhero while using Tool Router?

Yes, absolutely. You can configure which Calendarhero 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.

How safe is my data with Composio Tool Router?

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 Calendarhero data and credentials are handled as safely as possible.

Used by agents from

Context
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai
Context
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai
Context
Letta
glean
HubSpot
Agent.ai
Altera
DataStax
Entelligence
Rolai

Never worry about agent reliability

We handle tool reliability, observability, and security so you never have to second-guess an agent action.