eBird MCP Server

Instructions

Implementation Reference

• src/index.ts:234-248 (handler)

  The handler function for the 'get_nearby_notable_observations' tool. It constructs parameters from input args, calls the shared makeRequest function to fetch notable observations near the given lat/lng from the eBird API, and returns the JSON-formatted result.

  async (args) => {
    const params: Record<string, string | number | boolean> = {
      lat: args.lat,
      lng: args.lng,
      back: args.back,
      detail: args.detail,
      dist: args.dist,
      hotspot: args.hotspot,
      sppLocale: args.spp_locale,
    };
    if (args.max_results) params.maxResults = args.max_results;
  
    const result = await makeRequest("/data/obs/geo/recent/notable", params);
    return { content: [{ type: "text", text: JSON.stringify(result, null, 2) }] };
  }

• src/index.ts:224-233 (schema)

  Zod schema defining the input parameters for the tool, including required lat/lng, optional back days, detail level, distance radius, hotspot filter, max results, and species locale.

  {
    lat: z.number().min(-90).max(90).describe("Latitude"),
    lng: z.number().min(-180).max(180).describe("Longitude"),
    back: z.number().min(1).max(30).default(14).describe("Number of days back to fetch"),
    detail: z.enum(["simple", "full"]).default("simple").describe("Level of detail"),
    dist: z.number().min(0).max(50).default(25).describe("Search radius in kilometers"),
    hotspot: z.boolean().default(false).describe("Only fetch from hotspots"),
    max_results: z.number().min(1).max(10000).optional().describe("Maximum observations to return"),
    spp_locale: z.string().default("en").describe("Language for common names"),
  },

• src/index.ts:221-249 (registration)

  Registration of the 'get_nearby_notable_observations' tool using McpServer.tool(), including name, description, input schema, and inline handler function.

  server.tool(
    "get_nearby_notable_observations",
    "Get notable/rare observations near a location.",
    {
      lat: z.number().min(-90).max(90).describe("Latitude"),
      lng: z.number().min(-180).max(180).describe("Longitude"),
      back: z.number().min(1).max(30).default(14).describe("Number of days back to fetch"),
      detail: z.enum(["simple", "full"]).default("simple").describe("Level of detail"),
      dist: z.number().min(0).max(50).default(25).describe("Search radius in kilometers"),
      hotspot: z.boolean().default(false).describe("Only fetch from hotspots"),
      max_results: z.number().min(1).max(10000).optional().describe("Maximum observations to return"),
      spp_locale: z.string().default("en").describe("Language for common names"),
    },
    async (args) => {
      const params: Record<string, string | number | boolean> = {
        lat: args.lat,
        lng: args.lng,
        back: args.back,
        detail: args.detail,
        dist: args.dist,
        hotspot: args.hotspot,
        sppLocale: args.spp_locale,
      };
      if (args.max_results) params.maxResults = args.max_results;
  
      const result = await makeRequest("/data/obs/geo/recent/notable", params);
      return { content: [{ type: "text", text: JSON.stringify(result, null, 2) }] };
    }
  );

• src/index.ts:19-36 (helper)

  Shared utility function used by all tools, including this one, to construct and make authenticated GET requests to the eBird API endpoints.

  async function makeRequest(endpoint: string, params: Record<string, string | number | boolean> = {}): Promise<unknown> {
    const url = new URL(`${BASE_URL}${endpoint}`);
    Object.entries(params).forEach(([key, value]) => {
      if (value !== undefined && value !== null) {
        url.searchParams.append(key, String(value));
      }
    });
  
    const response = await fetch(url.toString(), {
      headers: { "X-eBirdApiToken": API_KEY! },
    });
  
    if (!response.ok) {
      throw new Error(`eBird API error: ${response.status} ${response.statusText}`);
    }
  
    return response.json();
  }