EventHorizon MCP Server

Instructions

Implementation Reference

• src/index.ts:286-299 (handler)

  The asynchronous handler function for the 'manage_registration' MCP tool. It retrieves the API client, calls manageRegistration on it, formats the response using formatRegistration, and returns success or error content.

  async ({ registration_id, action }) => {
    try {
      const apiClient = getClient();
      const registration = await apiClient.manageRegistration(registration_id, action);
      return {
        content: [{ type: 'text', text: `Registration ${action}d successfully!\n\n${formatRegistration(registration)}` }]
      };
    } catch (error) {
      return {
        content: [{ type: 'text', text: `Error: ${error instanceof Error ? error.message : String(error)}` }],
        isError: true
      };
    }
  }

• src/index.ts:282-285 (schema)

  Zod input schema for the 'manage_registration' tool defining parameters: registration_id (number) and action (one of 'approve', 'waitlist', 'cancel').

  {
    registration_id: z.number().describe('The ID of the registration to manage'),
    action: z.enum(['approve', 'waitlist', 'cancel']).describe('Action to take on the registration')
  },

• src/index.ts:279-300 (registration)

  MCP server.tool registration for the 'manage_registration' tool, specifying name, description, input schema, and handler function.

  server.tool(
    'manage_registration',
    'Manage a registration (approve, waitlist, or cancel). Only available to the event organizer.',
    {
      registration_id: z.number().describe('The ID of the registration to manage'),
      action: z.enum(['approve', 'waitlist', 'cancel']).describe('Action to take on the registration')
    },
    async ({ registration_id, action }) => {
      try {
        const apiClient = getClient();
        const registration = await apiClient.manageRegistration(registration_id, action);
        return {
          content: [{ type: 'text', text: `Registration ${action}d successfully!\n\n${formatRegistration(registration)}` }]
        };
      } catch (error) {
        return {
          content: [{ type: 'text', text: `Error: ${error instanceof Error ? error.message : String(error)}` }],
          isError: true
        };
      }
    }
  );

• src/index.ts:41-49 (helper)

  Utility function to format Registration data into a readable string for tool responses.

  function formatRegistration(reg: Registration): string {
    const eventInfo = typeof reg.event === 'object' ? reg.event.title : `Event ID: ${reg.event}`;
    const userInfo = typeof reg.user === 'object' ? reg.user.username : `User ID: ${reg.user}`;
    return `Registration (ID: ${reg.id})
    Event: ${eventInfo}
    User: ${userInfo}
    Status: ${reg.status}
    Registered at: ${reg.registered_at}`;
  }

• src/api-client.ts:182-189 (helper)

  EventHorizonClient method that sends POST request to manage a specific registration via the backend API.

  async manageRegistration(registrationId: number, action: 'approve' | 'waitlist' | 'cancel'): Promise<Registration> {
    try {
      const response: AxiosResponse<Registration> = await this.client.post(`/api/registrations/${registrationId}/manage/`, { action });
      return response.data;
    } catch (error) {
      throw new Error(`Failed to manage registration ${registrationId}: ${getErrorMessage(error)}`);
    }
  }