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_CONNECTIONSwith toolkitoutlook - •Always call
RUBE_SEARCH_TOOLSfirst 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.
- •Verify Rube MCP is available by confirming
RUBE_SEARCH_TOOLSresponds - •Call
RUBE_MANAGE_CONNECTIONSwith toolkitoutlook - •If connection is not ACTIVE, follow the returned auth link to complete Microsoft OAuth
- •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:
- •
OUTLOOK_LIST_CALENDARS- List available calendars [Optional] - •
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 online_meeting_provider='teamsForBusiness'
- •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:
- •
OUTLOOK_GET_MAILBOX_SETTINGS- Get user timezone for accurate queries [Prerequisite] - •
OUTLOOK_LIST_EVENTS- Search events with filters [Required] - •
OUTLOOK_GET_EVENT- Get full details for a specific event [Optional] - •
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:
- •
OUTLOOK_LIST_EVENTS- Find the event to update [Prerequisite] - •
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:
- •
OUTLOOK_DELETE_EVENT- Delete an event [Optional] - •
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:
- •
OUTLOOK_FIND_MEETING_TIMES- Get meeting time suggestions [Required] - •
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_SETTINGSwith 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
| Task | Tool Slug | Key Params |
|---|---|---|
| Create event | OUTLOOK_CALENDAR_CREATE_EVENT | subject, start_datetime, end_datetime, time_zone |
| List events | OUTLOOK_LIST_EVENTS | filter, select, top, timezone |
| Get event details | OUTLOOK_GET_EVENT | event_id |
| Calendar view | OUTLOOK_GET_CALENDAR_VIEW | start_datetime, end_datetime |
| Update event | OUTLOOK_UPDATE_CALENDAR_EVENT | event_id, subject, start_datetime |
| Delete event | OUTLOOK_DELETE_EVENT | event_id, send_notifications |
| Decline event | OUTLOOK_DECLINE_EVENT | event_id, comment |
| Find meeting times | OUTLOOK_FIND_MEETING_TIMES | attendees, meetingDuration |
| Get schedule | OUTLOOK_GET_SCHEDULE | Schedules, StartTime, EndTime |
| List calendars | OUTLOOK_LIST_CALENDARS | user_id |
| Mailbox settings | OUTLOOK_GET_MAILBOX_SETTINGS | select |
When to Use
This skill is applicable to execute the workflow or actions described in the overview.
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