Google Calendar MCP Server

Instructions

Implementation Reference

• src/index.ts:378-421 (handler)

  The main handler function for the 'create_event' tool. It constructs an event object from the validated arguments and uses the Google Calendar API to insert the new event, returning success or error response.

  async function handleCreateEvent(args: z.infer<typeof CreateEventArgsSchema>) {
    try {
      const event = {
        summary: args.summary,
        description: args.description,
        start: args.start,
        end: args.end,
        location: args.location,
        attendees: args.attendees,
        recurrence: args.recurrence,
      };
  
      const response = await calendar.events.insert({
        calendarId: args.calendarId,
        requestBody: event,
      });
  
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify({
              success: true,
              event: response.data,
              message: `Event "${args.summary}" created successfully`,
            }, null, 2),
          },
        ],
      };
    } catch (error) {
      return {
        content: [
          {
            type: "text",
            text: JSON.stringify({
              success: false,
              error: error instanceof Error ? error.message : "Unknown error",
            }, null, 2),
          },
        ],
        isError: true,
      };
    }
  }

• src/index.ts:47-65 (schema)

  Zod schema defining the input parameters for the 'create_event' tool, used for validation before calling the handler.

  const CreateEventArgsSchema = z.object({
    calendarId: z.string().optional().default("primary"),
    summary: z.string(),
    description: z.string().optional(),
    start: z.object({
      dateTime: z.string(),
      timeZone: z.string().optional(),
    }),
    end: z.object({
      dateTime: z.string(),
      timeZone: z.string().optional(),
    }),
    location: z.string().optional(),
    attendees: z.array(z.object({
      email: z.string(),
      displayName: z.string().optional(),
    })).optional(),
    recurrence: z.array(z.string()).optional(),
  });

• src/index.ts:152-222 (registration)

  Tool registration in the tools array, defining the name, description, and input schema for 'create_event' returned by ListToolsRequestHandler.

    name: "create_event",
    description: "Create a new event in Google Calendar",
    inputSchema: {
      type: "object",
      properties: {
        calendarId: {
          type: "string",
          description: "Calendar ID (default: 'primary')",
          default: "primary",
        },
        summary: {
          type: "string",
          description: "Event title/summary",
        },
        description: {
          type: "string",
          description: "Event description",
        },
        start: {
          type: "object",
          properties: {
            dateTime: {
              type: "string",
              description: "Start date and time (RFC3339 timestamp)",
            },
            timeZone: {
              type: "string",
              description: "Time zone (e.g., 'America/New_York')",
            },
          },
          required: ["dateTime"],
        },
        end: {
          type: "object",
          properties: {
            dateTime: {
              type: "string",
              description: "End date and time (RFC3339 timestamp)",
            },
            timeZone: {
              type: "string",
              description: "Time zone (e.g., 'America/New_York')",
            },
          },
          required: ["dateTime"],
        },
        location: {
          type: "string",
          description: "Event location",
        },
        attendees: {
          type: "array",
          items: {
            type: "object",
            properties: {
              email: { type: "string" },
              displayName: { type: "string" },
            },
            required: ["email"],
          },
          description: "List of attendees",
        },
        recurrence: {
          type: "array",
          items: { type: "string" },
          description: "Recurrence rules (RRULE format)",
        },
      },
      required: ["summary", "start", "end"],
    },
  },

• src/index.ts:551-554 (registration)

  Dispatch case in the CallToolRequestHandler switch statement that validates arguments using the schema and calls the handleCreateEvent function.

  case "create_event": {
    const validatedArgs = CreateEventArgsSchema.parse(args);
    return await handleCreateEvent(validatedArgs);
  }