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Google Calendar
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Google Calendar integration

Google Calendar is Google's scheduling service for consumer and Google Workspace accounts.

It can be connected to Agen.co two ways, matching the Official / In-house filter in the connector picker:

  • Official — Agen.co connects through Google's own hosted Calendar MCP server, so your AI agents use the same calendar, event, and free/busy tools Google exposes to MCP clients like Claude and Antigravity.
  • In-house — Agen.co wraps the Google Calendar API directly through its own integration layer, using a dedicated OAuth client you register in Google Cloud Console.

Pick Official if the built-in MCP tools cover what your agents need. Fall back to In-house if you need broader API coverage.

Connect via the official MCP server

Prerequisites

  • A Google account with access to Google Cloud Console
  • A Google Cloud project with the Google Calendar API and Calendar MCP API enabled

Create an OAuth client for MCP access

  1. In Google Cloud Console, select your project and enable the Google Calendar API and Calendar MCP API.
  2. Go to APIs & Services → Credentials and click Create credentials → OAuth client ID.
  3. Set Application type to Web application and give it a name (for example, Agen.co Google Calendar MCP).
  4. Switch back to Agen.co, go to Connectors → My connectors, click Add connector, and in the search bar type Google Calendar and select it from the results.
  5. Get back to Google Cloud Console. Under Authorized redirect URIs, click Add URI and add both URLs Agen.co generates when you open the Add Google Calendar panel with Official selected:
    • Callback URL — completes the initial OAuth handshake between Agen.co and your OAuth client.
    • Gateway callback URL — used by the Agen.co MCP gateway for per-user authorization at runtime.
  6. Click Create, then copy the Client ID and Client Secret — the Client Secret is shown only once.

Keep your Client Secret safe

The Client Secret is shown only once. If you lose it, return to the client's detail page and generate a new one.

  1. In the left sidebar, go to APIs & Services → OAuth consent screen → Data access, and add the following scopes:
ScopeDescription
https://www.googleapis.com/auth/calendar.calendarlist.readonlyList the user's calendars
https://www.googleapis.com/auth/calendar.events.readonlyRead events
https://www.googleapis.com/auth/calendar.events.freebusyRead free/busy information
https://www.googleapis.com/auth/calendar.eventsCreate, update, delete, and respond to events
  1. Return to the Agen.co portal — the Add Google Calendar panel should already be open from step 4. Fill in the fields:
FieldRequiredDescription
Instance SlugYesPrefixes each imported tool as slug__tool, so a second instance of the same connector needs a slug of its own. Use lowercase kebab-case. You can change it later from the connector's settings.
Client IDYesThe Client ID from the OAuth client you created above.
Client SecretYesThe Client Secret from the OAuth client you created above.
  1. Click Connect.
  2. You're redirected to Google to sign in and approve access.
  3. Return to Agen.co and click Add below the list of tools that were added.

Once connected, Google Calendar appears under My connectors with tools spanning:

AreaWhat it covers
CalendarsListing the user's calendars
EventsCreating, reading, searching, updating, deleting, and responding to events
AvailabilityQuerying free/busy information

Enabling the Google Calendar connector isn't enough on its own. Tool calls remain denied until you create a policy that grants access to the specific tools you want to expose.

Connect via the Google Calendar API

Integrating Google Calendar with Frontegg allows your application to create and manage calendar events, list and update calendars, query free/busy information, and access user settings — all through Frontegg's integration layer using Google OAuth 2.0.

Prerequisites

  • A Google account with access to Google Cloud Console
  • A Google Cloud project (you can create one during setup)

Enable the Google Calendar API

Step 1: Open the Google Calendar API in the API library

Go to the Google Calendar API page in the Google Cloud Console. Select your project from the top navigation, then click Enable if the API is not yet enabled. If you see Manage and API Enabled, the API is already active.

Google Calendar API page in Google Cloud Console

Create an OAuth client

Step 2: Go to the Credentials page

In the left sidebar, navigate to APIs & Services → Credentials. Click Create credentials.

Credentials page with Create credentials button highlighted

Step 3: Select OAuth client ID

From the dropdown, select OAuth client ID.

Create credentials dropdown with OAuth client ID highlighted

Step 4: Configure the OAuth client

On the Create OAuth client ID page:

  1. Set Application type to Web application.
  2. Enter a name for the client (for example, Frontegg Google Calendar Integration).
  3. Under Authorized redirect URIs, click Add URI and add both of the following:
    • https://YOUR_MCP_GATEWAY_URL/integration-callback

OAuth client form with name and redirect URIs filled in

Step 5: Create the client

Click Create to save the OAuth client. A dialog will display your Client ID and Client Secret — copy both values and store them securely.

Save your Client Secret now

The Client Secret is only shown once in this dialog. After you close it, you cannot retrieve it again — you can only create a new secret.

OAuth client created dialog showing Client ID and blurred Client Secret

Copy your credentials

Step 6: Copy the Client ID from the credentials list

After closing the dialog, your new client appears at the top of the OAuth 2.0 Client IDs list on the Credentials page.

Credentials page showing the new Frontegg Google Calendar Integration client

Step 7: View Client ID in the client detail page

Click the client name to open its detail page. You can view and copy the Client ID at any time from the Additional information section.

OAuth client detail page showing Client ID

Configure the Frontegg portal

Once you have your Client ID and Client Secret, enter them in the Frontegg portal:

  1. Open the Frontegg portal and navigate to [ENVIRONMENT] → Integrations → Google Calendar.
  2. Enter the Client ID and Client Secret in the corresponding fields.
  3. Select the required scopes:
ScopeDescription
https://www.googleapis.com/auth/calendar.events.readonlyList and read events
https://www.googleapis.com/auth/calendar.eventsCreate, update, patch, delete, respond to, and quick-add events
https://www.googleapis.com/auth/calendar.calendars.readonlyRead a single calendar
https://www.googleapis.com/auth/calendar.calendarlist.readonlyList the user's calendars
https://www.googleapis.com/auth/calendar.calendarsCreate, update, and delete calendars
https://www.googleapis.com/auth/calendar.freebusyQuery free/busy information
https://www.googleapis.com/auth/calendar.settings.readonlyRead calendar settings
  1. Click Save.

Keep your credentials secure

Never share or commit your Client Secret to version control.

Additional resources