Outlook Meetings Scheduler MCP Server

Instructions

Implementation Reference

• src/tools/event-update.ts:33-166 (handler)

  The main handler function for the 'update-event' tool, which updates calendar event details including subject, body, dates, location, and attendees using the Microsoft Graph API.
  async ({ eventId, subject, body, start, end, timeZone, location, attendees }) => { const { graph, userEmail, authError } = await getGraphConfig(); if (authError) { return { content: [{ type: "text", text: `🔐 Authentication Required\n\n${authError}\n\nPlease complete the authentication and try again.` }] }; } // Create the event update object with only properties that should be updated const eventUpdates: Partial<Event> = {}; if (subject) { eventUpdates.subject = subject; } if (body) { eventUpdates.body = { contentType: "html", content: `${body}<br/>Updated around ${format(new Date(), 'dd-MMM-yyyy HH:mm')}` }; } if (start) { eventUpdates.start = { dateTime: start, timeZone: timeZone || undefined }; } if (end) { eventUpdates.end = { dateTime: end, timeZone: timeZone || undefined }; } if (location) { eventUpdates.location = { displayName: location }; } // Handle attendees if provided if (attendees && attendees.length > 0) { // First get the current event to merge with existing attendees const currentEvent = await graph.getEvent(eventId, userEmail); if (!currentEvent || !currentEvent.attendees) { // If no current attendees, just use the new ones const formattedAttendees: Attendee[] = attendees.map((attendee: any) => ({ emailAddress: { address: attendee.email, name: attendee.name || attendee.email }, type: attendee.type || "required" })); eventUpdates.attendees = formattedAttendees; } else { // Merge with existing attendees, avoiding duplicates const existingAttendees = currentEvent.attendees || []; const existingEmails = new Set( existingAttendees .filter((a: Attendee) => a.emailAddress?.address) .map((a: Attendee) => a.emailAddress!.address!.toLowerCase()) ); // Format new attendees const newAttendees: Attendee[] = attendees .filter((a: any) => !existingEmails.has(a.email.toLowerCase())) .map((attendee: any) => ({ emailAddress: { address: attendee.email, name: attendee.name || attendee.email }, type: attendee.type || "required" })); // Combine existing and new attendees eventUpdates.attendees = [...existingAttendees, ...newAttendees]; } } // First get the current event to show what's being updated const currentEvent = await graph.getEvent(eventId, userEmail); if (!currentEvent) { return { content: [ { type: "text", text: "Could not find the event to update. Please check the event ID.", }, ], }; } // Call the Graph API to update the event const result = await graph.updateEvent(eventId, eventUpdates, userEmail); if (!result) { return { content: [ { type: "text", text: "Failed to update calendar event. Check the logs for details.", }, ], }; } // Format the result for response const eventUrl = result.webLink || "No event URL available"; const successMessage = ` Calendar event updated successfully! Event ID: ${eventId} ${subject ? `New Subject: ${subject}\nPrevious: ${currentEvent.subject || "No subject"}` : ''} ${start ? `New Start: ${start}\nPrevious: ${currentEvent.start?.dateTime || "No start time"}` : ''} ${end ? `New End: ${end}\nPrevious: ${currentEvent.end?.dateTime || "No end time"}` : ''} ${location ? `New Location: ${location}\nPrevious: ${currentEvent.location?.displayName || "No location"}` : ''} Event URL: ${eventUrl} `; return { content: [ { type: "text", text: successMessage, }, ], }; }
• src/tools/event-update.ts:17-32 (schema)

  Zod schema defining the input parameters for the 'update-event' tool.
  { eventId: z.string().describe("ID of the event to update"), subject: z.string().optional().describe("New subject for the calendar event"), body: z.string().optional().describe("New content/body for the calendar event"), start: z.string().optional().describe("New start time in ISO format (e.g. 2025-04-20T12:00:00)"), end: z.string().optional().describe("New end time in ISO format (e.g. 2025-04-20T13:00:00)"), timeZone: z.string().optional().describe("New time zone for the event"), location: z.string().optional().describe("New location for the event"), attendees: z.array( z.object({ email: z.string().describe("Email address of the attendee"), name: z.string().optional().describe("Name of the attendee"), type: z.enum(["required", "optional"]).optional().describe("Type of attendee: required or optional") }) ).optional().describe("List of attendees to add or update for the event"), },
• src/tools/event-update.ts:13-167 (registration)

  The registerTool call that registers the 'update-event' tool with the MCP server, including name, description, schema, and handler.
  registerTool( server, "update-event", "Update an existing calendar event", { eventId: z.string().describe("ID of the event to update"), subject: z.string().optional().describe("New subject for the calendar event"), body: z.string().optional().describe("New content/body for the calendar event"), start: z.string().optional().describe("New start time in ISO format (e.g. 2025-04-20T12:00:00)"), end: z.string().optional().describe("New end time in ISO format (e.g. 2025-04-20T13:00:00)"), timeZone: z.string().optional().describe("New time zone for the event"), location: z.string().optional().describe("New location for the event"), attendees: z.array( z.object({ email: z.string().describe("Email address of the attendee"), name: z.string().optional().describe("Name of the attendee"), type: z.enum(["required", "optional"]).optional().describe("Type of attendee: required or optional") }) ).optional().describe("List of attendees to add or update for the event"), }, async ({ eventId, subject, body, start, end, timeZone, location, attendees }) => { const { graph, userEmail, authError } = await getGraphConfig(); if (authError) { return { content: [{ type: "text", text: `🔐 Authentication Required\n\n${authError}\n\nPlease complete the authentication and try again.` }] }; } // Create the event update object with only properties that should be updated const eventUpdates: Partial<Event> = {}; if (subject) { eventUpdates.subject = subject; } if (body) { eventUpdates.body = { contentType: "html", content: `${body}<br/>Updated around ${format(new Date(), 'dd-MMM-yyyy HH:mm')}` }; } if (start) { eventUpdates.start = { dateTime: start, timeZone: timeZone || undefined }; } if (end) { eventUpdates.end = { dateTime: end, timeZone: timeZone || undefined }; } if (location) { eventUpdates.location = { displayName: location }; } // Handle attendees if provided if (attendees && attendees.length > 0) { // First get the current event to merge with existing attendees const currentEvent = await graph.getEvent(eventId, userEmail); if (!currentEvent || !currentEvent.attendees) { // If no current attendees, just use the new ones const formattedAttendees: Attendee[] = attendees.map((attendee: any) => ({ emailAddress: { address: attendee.email, name: attendee.name || attendee.email }, type: attendee.type || "required" })); eventUpdates.attendees = formattedAttendees; } else { // Merge with existing attendees, avoiding duplicates const existingAttendees = currentEvent.attendees || []; const existingEmails = new Set( existingAttendees .filter((a: Attendee) => a.emailAddress?.address) .map((a: Attendee) => a.emailAddress!.address!.toLowerCase()) ); // Format new attendees const newAttendees: Attendee[] = attendees .filter((a: any) => !existingEmails.has(a.email.toLowerCase())) .map((attendee: any) => ({ emailAddress: { address: attendee.email, name: attendee.name || attendee.email }, type: attendee.type || "required" })); // Combine existing and new attendees eventUpdates.attendees = [...existingAttendees, ...newAttendees]; } } // First get the current event to show what's being updated const currentEvent = await graph.getEvent(eventId, userEmail); if (!currentEvent) { return { content: [ { type: "text", text: "Could not find the event to update. Please check the event ID.", }, ], }; } // Call the Graph API to update the event const result = await graph.updateEvent(eventId, eventUpdates, userEmail); if (!result) { return { content: [ { type: "text", text: "Failed to update calendar event. Check the logs for details.", }, ], }; } // Format the result for response const eventUrl = result.webLink || "No event URL available"; const successMessage = ` Calendar event updated successfully! Event ID: ${eventId} ${subject ? `New Subject: ${subject}\nPrevious: ${currentEvent.subject || "No subject"}` : ''} ${start ? `New Start: ${start}\nPrevious: ${currentEvent.start?.dateTime || "No start time"}` : ''} ${end ? `New End: ${end}\nPrevious: ${currentEvent.end?.dateTime || "No end time"}` : ''} ${location ? `New Location: ${location}\nPrevious: ${currentEvent.location?.displayName || "No location"}` : ''} Event URL: ${eventUrl} `; return { content: [ { type: "text", text: successMessage, }, ], }; } );
• src/index.ts:35-35 (registration)

  Top-level registration call in the main server file that invokes registerEventUpdateTools to add the 'update-event' tool to the MCP server.
  registerEventUpdateTools(server);