Outlook Calendar MCP server

The Outlook Calendar MCP server enables LLMs to read, interpret, and modify calendar data stored in Microsoft Outlook Calendar through natural conversation. It provides tools to retrieve events, check availability, and create, update, or delete calendar entries without requiring direct interaction with the Outlook interface.

Uses

Use the Outlook Calendar MCP server when you plan to perform the following actions:

• View upcoming or past calendar events for planning or reporting
• Check availability for yourself or other attendees to support scheduling
• Retrieve full details for specific events
• Schedule new meetings, focus time, or out-of-office events
• Reschedule, update, or cancel existing calendar events
• Access multiple calendars including shared and delegate calendars
• Find open time slots for meetings or personal time
• Manage recurring meetings and series

Example prompts

• What's on my calendar for this week?
• Schedule a 30-minute meeting with Alex and Priya next Tuesday.
• When am I free tomorrow afternoon?
• Get the details for my 2pm meeting today.
• Move my standup meeting to 10am instead of 9am.
• Cancel the budget review meeting on Friday.
• What calendars do I have access to?
• Find a time when Sarah and I are both free this week.

Outlook Calendar MCP server tools

The Outlook Calendar MCP server provides the following tools:

Tool	Description
list_events	Retrieves calendar events from one or more Outlook calendars within a time window you specify or by direction and count.
get_event	Retrieves full details for a single Outlook Calendar event by unique ID.
get_availability	Retrieves free or busy availability for the user and attendees over a time window you specify.
create_event	Creates a new Outlook Calendar event on a calendar the user is allowed to modify.
update_event	Updates an existing Outlook Calendar event with new details, including time, attendees, description, or recurrence.
delete_event	Deletes or cancels an existing Outlook Calendar event identified by its unique ID.
list_calendars	Retrieves the list of Outlook calendars accessible to the user.

Install the Outlook Calendar MCP server

Complete the following steps to install a prebuilt MCP server to your project:

1

Sign in to your Workato account.

2

Go to AI Hub > MCP servers.

3

Click + Create MCP server.

4

Go to the Start with a template section and select the prebuilt MCP server you plan to use.

5

Click Use this template.

6

Provide a name for your MCP server in the MCP server name field.

7

Go to the Connections section and connect to your app account.

8

Select the connection type you plan to use for the MCP server template.

• User's connection: MCP server tools perform actions based on the identity and permissions of the user who connects to the application. Users authenticate with their own credentials to execute the skill.
• Your connection: This option uses the connection established by the recipe builder and follows the same principles as normal app connections.

Select your connection type

VERIFIED USER ACCESS AUTHENTICATION REQUIREMENTS

Only app connections that use OAuth 2.0 authorization code grant are available for user's connection. Refer to Verified user access for more information.

9

Complete the app-specific connection setup steps in the following section.

Outlook Calendar connection setup

Workato supports the following types of connections to Outlook:

• Authorization code grant authentication (OAuth 2.0)
• Client credentials-based authentication (OAuth 2.0): Only available for tenant-specific connections

MICROSOFT MFA ENFORCEMENT

Microsoft is rolling out mandatory multi-factor authentication (MFA) (opens new window) gradually to different applications and accounts in phases. This enforcement will continue throughout 2025 and beyond.

We strongly recommend enabling MFA now for all Microsoft accounts used with Workato to avoid service disruptions from short-notice enforcement changes.

Complete the following steps to maintain uninterrupted service:

1

Enable MFA for your Microsoft organization following Microsoft's MFA setup guide (opens new window).

2

Reconnect your Microsoft connection in Workato.

3

Complete the OAuth flow with MFA when prompted.

4

Test your recipes to ensure they work with the updated connection.

Authorization code grant authentication (OAuth 2.0)

This authentication method requires the following value for tenant-specific account types:

• Tenant ID/Domain

Register the Workato App in Azure portal

Complete the following steps to register the Workato app and assign it permissions for authorization code grant connections:

View Register the Workato app in the Azure Portal steps

1

Register the Workato app in the Azure Portal

1

Sign in to the Azure portal (opens new window).

2

Select App registrations > + New registration, under Azure services.

3

Enter a unique name for the application and select a Supported account type.

4

Select Web from the Select a platform drop-down menu.

5

Enter https://www.workato.com/oauth/callback as the Redirect URI and select Register.

Register an app

2

Assign permissions to your app

1

In the navigation sidebar, select Manage > API permissions.

2

Click + Add a permission and select Microsoft Graph APIs.

3

Add the required permissions as outlined in the Permissions required to connect section. Depending on your connection type, you must assign Application or Delegated permissions.

Add permissions

4

Click Add permissions.

Admin consent is required for specific permissions. Refer to the Granting admin consent section to learn more.

3

Obtain the Directory (tenant ID) from the Azure portal

This step is required if you plan to use a tenant-specific account. You can skip this step if you plan to use a common, consumer, or organization account type for your connection.

1

Go to the Overview > Essentials section.

App details

2

Copy the Directory (tenant) ID for use in Workato.

Complete setup in Workato

View Complete setup in Workato steps

Complete the following steps to set up the connection in Workato:

1

Click Create > Connection.

2

Search for and select Outlook as your connection in the New connection page.

3

Provide a name for your connection in the Connection name field.

4

Use the Location drop-down menu to select the project where you plan to store the connection.

5

Use the Connection account type drop-down menu to select the type of account you plan to use. The available choices are Common, Tenant-specific, Consumer, and Organization.

• Common: This option allows you to sign in using enterprise and multi-tenant accounts that are not restricted to a specific organization (tenant).

Common connections

• Tenant specific: This option is specifically designed for users who belong to a particular organization (tenant).

Tenant specific connections

Provide the tenant ID of the Microsoft Entra ID tenant (a GUID) or its tenant domain in the Tenant ID/Domain field. This ensures that you access resources specifically configured for that tenant. Learn how to obtain this value.

• Consumer: This option supports personal Microsoft accounts.

Consumer connections

• Organization: This option supports work or school accounts.

Organization connections

6

Select Authorization code grant as the Authentication type.

7

Optional. By default, the connector requests a set of scopes necessary for all triggers and actions to function properly. In the Advanced settings section, you can manually select the permissions instead. The minimum permissions required to establish a connection are User.Read and offline_access. Workato always requests these permissions regardless of the permissions you select. Refer to the permissions section for more information.

8

Click Sign in with Microsoft.

Client credentials-based authentication (OAuth 2.0)

This method requires the following fields:

• Tenant ID/Domain
• User ID
• Client ID
• Client Secret

COMPATIBLE AUTHENTICATION

Client credentials-based authentication is only compatible with tenant-specific connections.

Register the Workato App in the Azure Portal

Complete the following steps to register the Workato app and assign it permissions for client credentials-based connections:

View Register the Workato App in the Azure Portal steps

1

Register the Workato App in the Azure Portal

1

Sign in to the Azure portal (opens new window).

2

Select App registrations > + New registration, under Azure services.

3

Enter a unique name for the application and select a Supported account type.

4

Select Web from the Select a platform drop-down menu.

5

Enter https://www.workato.com/oauth/callback as the Redirect URI and select Register.

Register an app

2

Assign permissions to your app

1

In the navigation sidebar, select Manage > API permissions.

2

Click + Add a permission and select Microsoft Graph APIs.

3

Add the required permissions as outlined in the Permissions required to connect section. Depending on your connection type, you must assign Application or Delegated permissions.

Add permissions

4

Click Add permissions.

Admin consent is required for specific permissions. Refer to the Granting admin consent section to learn more.

3

Generate a client secret

1

Go to Manage > Certificates & Secrets > Client secrets.

2

Click + New client secret.

3

Provide a Description for the client secret and specify an expiry date.

4

Click Add.

5

Copy and save the client secret Value—not the Secret ID—for use in Workato.

Copy and save the client secret value

4

Obtain the Application (client) ID, Object ID, and Directory (tenant) ID from the Azure Portal

1

Go to the Overview > Essentials section.

App details

2

Copy the Application (client) ID, Object ID, and Directory (tenant) ID for use in Workato.

5

Obtain the User ID from the Azure Portal

1

Go to Home > Users to obtain the User ID.

Select users

2

Search for and select the default user you plan to use to perform operations. This user does not establish the connection but is required for performing certain operations that an app can't perform. It is also required in picklists to pull user data. For example the folder picklist populates folders belonging to the default user.

3

Copy the User principal name. Use this value as the User ID in Workato.

Return to Workato to finish setting up your connection.

Complete setup in Workato

View Complete setup in Workato steps

Complete the following steps to set up the connection in Workato:

1

Click Create > Connection.

2

Search for and select Outlook as your connection in the New connection page.

3

Provide a name for your connection in the Connection name field.

4

Use the Location drop-down menu to select the project where you plan to store the connection.

5

Select Tenant specific as the Connection account type. This option is specifically designed for users who belong to a particular organization (tenant).

6

Provide your Tenant ID/Domain. This is the Directory (tenant) ID for your app. Refer to the Register an app in Azure section to learn how to obtain this value.

7

Select Client credentials as the Authentication type.

8

Supply the User ID, Client ID, and Client secret for your app. Refer to the Register an app in Azure section to learn how to obtain these values.

9

Click Sign in with Microsoft.

How to use Outlook Calendar MCP server tools

Refer to the following sections for detailed information on available tools:

list_events tool

The list_events tool retrieves calendar events from one or more Outlook calendars within a time window you specify or by direction and count. Your LLM uses this tool to see what's on your calendar, plan your day or week, or review past events.

Try asking:

• What's on my calendar for this week?
• Show me my meetings for tomorrow.
• List all events on my calendar between January 1st and January 15th.
• What do I have scheduled for next Monday?

get_event tool

The get_event tool retrieves full details for a single Outlook Calendar event by its unique event ID. Your LLM uses this tool to read, inspect, or open a specific event, retrieve complete details before modifying or deleting the event, summarize a particular meeting, or confirm metadata prior to scheduling decisions.

Try asking:

• Get the details for my 2pm meeting today.
• Show me the full information for the quarterly review meeting.
• What are the details of my next appointment?
• Read the agenda for the product planning meeting.

get_availability tool

The get_availability tool retrieves free and busy availability for you and attendees over a time window you specify. Your LLM uses this tool to find times to schedule a meeting, check whether you or others are free, evaluate potential windows for rescheduling, or identify open periods for PTO or focus time.

Try asking:

• When am I free tomorrow afternoon?
• Find a time when Sarah and I are both free this week.
• Check my availability for Thursday between 2pm and 5pm.
• When are Alex, Mei, and I all available next week?

create_event tool

The create_event tool creates a new Outlook Calendar event. Your LLM uses this tool to schedule a new meeting or call, add a calendar hold or focus time block, create a recurring event, block off PTO or OOO time, or create follow-up meetings.

Try asking:

• Schedule a 30-minute meeting with Marco and Jade next Tuesday at 2pm.
• Create a recurring weekly standup every Monday at 9am.
• Block off next Friday as PTO.
• Set up a focus time block for tomorrow morning from 9am to 11am.

update_event tool

The update_event tool updates an existing Outlook Calendar event with new details including time, attendees, description, or recurrence. Your LLM uses this tool to move or reschedule a meeting, shorten or extend an event's duration, add, remove, or update attendees, update meeting descriptions or agendas, or modify a recurring series.

Try asking:

• Move my standup meeting to 10am instead of 9am.
• Reschedule the budget review to next Wednesday.
• Add Josh to the product planning meeting.
• Extend my 1pm meeting by 30 minutes.

delete_event tool

The delete_event tool deletes or cancels an existing Outlook Calendar event identified by its unique ID. Your LLM uses this tool to cancel meetings, remove calendar blocks, or delete events that are no longer needed.

Try asking:

• Cancel the budget review meeting on Friday.
• Delete my 3pm appointment tomorrow.
• Remove the team lunch from my calendar.
• Cancel the recurring standup for next week only.

list_calendars tool

The list_calendars tool retrieves the list of Outlook calendars accessible to you, including default, secondary, shared, and delegate calendars. Your LLM uses this tool to discover available calendars, select a specific calendar for operations, or understand your calendar access.

Try asking:

• What calendars do I have access to?
• Show me all my Outlook calendars.
• List the shared calendars I can view.
• What calendars are available for scheduling?

Getting started

View and manage your MCP server tools in the Overview page Tools section. Tool management provides the following capabilities:

• Start tools
• Remove tools
• Edit tools
• Add tools
• Edit your LLM-facing MCP server description

TOOLS MUST BE STARTED

Your LLM can only access active tools in your MCP server connector.