Outlook Calendar Automation

Outlook Calendar Automation via Rube MCP

Automate Outlook Calendar operations through Composio's Outlook toolkit via Rube MCP.

Prerequisites

• Rube MCP must be connected (RUBE_SEARCH_TOOLS available)
• Active Outlook connection via RUBE_MANAGE_CONNECTIONS with toolkit outlook
• Always call RUBE_SEARCH_TOOLS first to get current tool schemas

Setup

Get Rube MCP: Add https://rube.app/mcp as an MCP server in your client configuration. No API keys needed — just add the endpoint and it works.

1. Verify Rube MCP is available by confirming RUBE_SEARCH_TOOLS responds
2. Call RUBE_MANAGE_CONNECTIONS with toolkit outlook
3. If connection is not ACTIVE, follow the returned auth link to complete Microsoft OAuth
4. Confirm connection status shows ACTIVE before running any workflows

Core Workflows

1. Create Calendar Events

When to use: User wants to schedule a new event on their Outlook calendar

Tool sequence:

1. OUTLOOK_LIST_CALENDARS - List available calendars [Optional]
2. OUTLOOK_CALENDAR_CREATE_EVENT - Create the event [Required]

Key parameters:

• subject: Event title
• start_datetime: ISO 8601 start time (e.g., '2025-01-03T10:00:00')
• end_datetime: ISO 8601 end time (must be after start)
• time_zone: IANA or Windows timezone (e.g., 'America/New_York', 'Pacific Standard Time')
• attendees_info: Array of email strings or attendee objects
• body: Event description (plain text or HTML)
• is_html: Set true if body contains HTML
• location: Physical location string
• is_online_meeting: Set true for Teams meeting link
• online_meeting_provider: 'teamsForBusiness' for Teams integration
• show_as: 'free', 'tentative', 'busy', 'oof'

Pitfalls:

• start_datetime must be chronologically before end_datetime
• time_zone is required and must be a valid IANA or Windows timezone name
• Adding attendees can trigger invitation emails immediately
• To generate a Teams meeting link, set BOTH is_online_meeting=true AND>
• user_id defaults to 'me'; use email or UUID for other users' calendars

2. List and Search Events

When to use: User wants to find events on their calendar

Tool sequence:

1. OUTLOOK_GET_MAILBOX_SETTINGS - Get user timezone for accurate queries [Prerequisite]
2. OUTLOOK_LIST_EVENTS - Search events with filters [Required]
3. OUTLOOK_GET_EVENT - Get full details for a specific event [Optional]
4. OUTLOOK_GET_CALENDAR_VIEW - Get events active during a time window [Alternative]

Key parameters:

• filter: OData filter string (e.g., "start/dateTime ge '2024-07-01T00:00:00Z'")
• select: Array of properties to return
• orderby: Sort criteria (e.g., ['start/dateTime desc'])
• top: Results per page (1-999)
• timezone: Display timezone for results
• start_datetime/end_datetime: For CALENDAR_VIEW time window (UTC with Z suffix)

Pitfalls:

• OData filter datetime values require single quotes and Z suffix
• Use 'start/dateTime' for event start filtering, NOT 'receivedDateTime' (that is for emails)
• 'createdDateTime' supports orderby/select but NOT filtering
• Pagination: follow @odata.nextLink until all pages are collected
• CALENDAR_VIEW is better for "what's on my calendar today" queries (includes spanning events)
• LIST_EVENTS is better for keyword/category filtering
• Response events have start/end nested as start.dateTime and end.dateTime

3. Update Events

When to use: User wants to modify an existing calendar event

Tool sequence:

1. OUTLOOK_LIST_EVENTS - Find the event to update [Prerequisite]
2. OUTLOOK_UPDATE_CALENDAR_EVENT - Update the event [Required]

Key parameters:

• event_id: Unique event identifier (from LIST_EVENTS)
• subject: New event title (optional)
• start_datetime/end_datetime: New times (optional)
• time_zone: Timezone for new times
• attendees: Updated attendee list (replaces existing if provided)
• body: Updated description with contentType and content
• location: Updated location

Pitfalls:

• UPDATE merges provided fields with existing event; unspecified fields are preserved
• Providing attendees replaces the ENTIRE attendee list; include all desired attendees
• Providing categories replaces the ENTIRE category list
• Updating times may trigger re-sends to attendees
• event_id is required; obtain from LIST_EVENTS first

4. Delete Events and Decline Invitations

When to use: User wants to remove an event or decline a meeting invitation

Tool sequence:

1. OUTLOOK_DELETE_EVENT - Delete an event [Optional]
2. OUTLOOK_DECLINE_EVENT - Decline a meeting invitation [Optional]

Key parameters:

• event_id: Event to delete or decline
• send_notifications: Send cancellation notices to attendees (default true)
• comment: Reason for declining (for DECLINE_EVENT)
• proposedNewTime: Suggest alternative time when declining

Pitfalls:

• Deletion with send_notifications=true sends cancellation emails
• Declining supports proposing a new time with start/end in ISO 8601 format
• Deleting a recurring event master deletes all occurrences
• sendResponse in DECLINE_EVENT controls whether the organizer is notified

5. Find Available Meeting Times

When to use: User wants to find optimal meeting slots across multiple people

Tool sequence:

1. OUTLOOK_FIND_MEETING_TIMES - Get meeting time suggestions [Required]
2. OUTLOOK_GET_SCHEDULE - Check free/busy for specific people [Alternative]

Key parameters:

• attendees: Array of attendee objects with email and type
• meetingDuration: ISO 8601 duration (e.g., 'PT1H' for 1 hour, 'PT30M' for 30 min)
• timeConstraint: Time slots to search within
• minimumAttendeePercentage: Minimum confidence threshold (0-100)
• Schedules: Email array for GET_SCHEDULE
• StartTime/EndTime: Time window for schedule lookup (max 62 days)

Pitfalls:

• FIND_MEETING_TIMES searches within work hours by default; use activityDomain='unrestricted' for 24/7
• Time constraint time slots require dateTime and timeZone for both start and end
• GET_SCHEDULE period cannot exceed 62 days
• Meeting suggestions respect attendee availability but may return suboptimal times for complex groups

Common Patterns

Event ID Resolution

1. Call OUTLOOK_LIST_EVENTS with time-bound filter
2. Find target event by subject or other criteria
3. Extract event id (e.g., 'AAMkAGI2TAAA=')
4. Use in UPDATE, DELETE, or GET_EVENT calls

OData Filter Syntax for Calendar

Time range filter:

filter: "start/dateTime ge '2024-07-01T00:00:00Z' and start/dateTime le '2024-07-31T23:59:59Z'"

Subject contains:

filter: "contains(subject, 'Project Review')"

Combined:

filter: "contains(subject, 'Review') and categories/any(c:c eq 'Work')"

Timezone Handling

• Get user timezone: OUTLOOK_GET_MAILBOX_SETTINGS with select=['timeZone']
• Use consistent timezone in filter datetime values
• Calendar View requires UTC timestamps with Z suffix
• LIST_EVENTS filter accepts timezone in datetime values

Online Meeting Creation

1. Set is_online_meeting: true
2. Set online_meeting_provider: 'teamsForBusiness'
3. Create event with OUTLOOK_CALENDAR_CREATE_EVENT
4. Teams join link available in response onlineMeeting field
5. Or retrieve via OUTLOOK_GET_EVENT for the full join URL

Known Pitfalls

DateTime Formats:

• ISO 8601 format required: '2025-01-03T10:00:00'
• Calendar View requires UTC with Z: '2025-01-03T10:00:00Z'
• Filter values need single quotes: "'2025-01-03T00:00:00Z'"
• Timezone mismatches shift event boundaries; always resolve user timezone first

OData Filter Errors:

• 400 Bad Request usually indicates filter syntax issues
• Not all event properties support filtering (createdDateTime does not)
• Retry with adjusted syntax/bounds on 400 errors
• Valid filter fields: start/dateTime, end/dateTime, subject, categories, isAllDay

Attendee Management:

• Adding attendees triggers invitation emails
• Updating attendees replaces the full list; include all desired attendees
• Attendee types: 'required', 'optional', 'resource'
• Calendar delegation affects which calendars are accessible

Response Structure:

• Events nested at response.data.value
• Event times at event.start.dateTime and event.end.dateTime
• Calendar View may nest at data.results[i].response.data.value
• Parse defensively with fallbacks for different nesting levels

Quick Reference

When to Use

This skill is applicable to execute the workflow or actions described in the overview.

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