National Parks MCP Server

Instructions

Implementation Reference

• src/handlers/getEvents.ts:6-44 (handler)

  The main handler function getEventsHandler that implements the core tool logic: processes arguments, fetches events from NPS API, formats and groups data by park, returns JSON response.
  export async function getEventsHandler(args: z.infer<typeof GetEventsSchema>) { // Set default limit if not provided or if it exceeds maximum const limit = args.limit ? Math.min(args.limit, 50) : 10; // Format the request parameters const requestParams = { limit, ...args }; const response = await npsApiClient.getEvents(requestParams); // Format the response for better readability by the AI const formattedEvents = formatEventData(response.data); // Group events by park code for better organization const eventsByPark: { [key: string]: any[] } = {}; formattedEvents.forEach(event => { if (!eventsByPark[event.parkCode]) { eventsByPark[event.parkCode] = []; } eventsByPark[event.parkCode].push(event); }); const result = { total: parseInt(response.total), limit: parseInt(response.limit), start: parseInt(response.start), events: formattedEvents, eventsByPark: eventsByPark }; return { content: [{ type: "text", text: JSON.stringify(result, null, 2) }] }; }
• src/schemas.ts:42-49 (schema)

  Zod input schema for the getEvents tool defining optional parameters: parkCode, limit, start, dateStart, dateEnd, q.
  export const GetEventsSchema = z.object({ parkCode: z.string().optional().describe('Filter events by park code (e.g., "yose" for Yosemite). Multiple parks can be comma-separated (e.g., "yose,grca").'), limit: z.number().optional().describe('Maximum number of events to return (default: 10, max: 50)'), start: z.number().optional().describe('Start position for results (useful for pagination)'), dateStart: z.string().optional().describe('Start date for filtering events (format: YYYY-MM-DD)'), dateEnd: z.string().optional().describe('End date for filtering events (format: YYYY-MM-DD)'), q: z.string().optional().describe('Search term to filter events by title or description') });
• src/server.ts:69-72 (registration)

  Registration of the getEvents tool in the ListToolsRequestHandler response, specifying name, description, and input schema.
  name: "getEvents", description: "Find upcoming events at parks", inputSchema: zodToJsonSchema(GetEventsSchema), },
• src/server.ts:110-113 (registration)

  Execution handler in CallToolRequestHandler switch statement: parses arguments using GetEventsSchema and delegates to getEventsHandler.
  case "getEvents": { const args = GetEventsSchema.parse(request.params.arguments); return await getEventsHandler(args); }
• src/utils/npsApiClient.ts:460-468 (helper)

  NPS API client helper method that fetches events data from the '/events' NPS API endpoint.
  async getEvents(params: EventQueryParams = {}): Promise<NPSResponse<EventData>> { try { const response = await this.api.get('/events', { params }); return response.data; } catch (error) { console.error('Error fetching events data:', error); throw error; } }