index.ts

#!/usr/bin/env node

import { Server } from "@modelcontextprotocol/sdk/server/index.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import {
  CallToolRequestSchema,
  ListToolsRequestSchema,
  Tool,
} from "@modelcontextprotocol/sdk/types.js";
import fetch from "node-fetch";

// Response interfaces
interface GoogleMapsResponse {
  status: string;
  error_message?: string;
}

interface GeocodeResponse extends GoogleMapsResponse {
  results: Array<{
    place_id: string;
    formatted_address: string;
    geometry: {
      location: {
        lat: number;
        lng: number;
      }
    };
    address_components: Array<{
      long_name: string;
      short_name: string;
      types: string[];
    }>;
  }>;
}

interface PlacesSearchResponse extends GoogleMapsResponse {
  results: Array<{
    name: string;
    place_id: string;
    formatted_address: string;
    geometry: {
      location: {
        lat: number;
        lng: number;
      }
    };
    rating?: number;
    types: string[];
  }>;
}

interface PlaceDetailsResponse extends GoogleMapsResponse {
  result: {
    name: string;
    place_id: string;
    formatted_address: string;
    formatted_phone_number?: string;
    website?: string;
    rating?: number;
    reviews?: Array<{
      author_name: string;
      rating: number;
      text: string;
      time: number;
    }>;
    opening_hours?: {
      weekday_text: string[];
      open_now: boolean;
    };
    geometry: {
      location: {
        lat: number;
        lng: number;
      }
    };
  };
}

interface DistanceMatrixResponse extends GoogleMapsResponse {
  origin_addresses: string[];
  destination_addresses: string[];
  rows: Array<{
    elements: Array<{
      status: string;
      duration: {
        text: string;
        value: number;
      };
      distance: {
        text: string;
        value: number;
      };
    }>;
  }>;
}

interface ElevationResponse extends GoogleMapsResponse {
  results: Array<{
    elevation: number;
    location: {
      lat: number;
      lng: number;
    };
    resolution: number;
  }>;
}

interface DirectionsResponse extends GoogleMapsResponse {
  routes: Array<{
    summary: string;
    legs: Array<{
      distance: {
        text: string;
        value: number;
      };
      duration: {
        text: string;
        value: number;
      };
      steps: Array<{
        html_instructions: string;
        distance: {
          text: string;
          value: number;
        };
        duration: {
          text: string;
          value: number;
        };
        travel_mode: string;
      }>;
    }>;
  }>;
}

function getApiKey(): string {
    const apiKey = process.env.GOOGLE_MAPS_API_KEY;
    if (!apiKey) {
      console.error("GOOGLE_MAPS_API_KEY environment variable is not set");
      process.exit(1);
    }
    return apiKey;
  }
  
const GOOGLE_MAPS_API_KEY = getApiKey();

// Tool definitions
const GEOCODE_TOOL: Tool = {
    name: "maps_geocode",
    description: "Convert an address into geographic coordinates",
    inputSchema: {
      type: "object",
      properties: {
        address: { 
          type: "string", 
          description: "The address to geocode" 
        }
      },
      required: ["address"]
    }
  };
  
const REVERSE_GEOCODE_TOOL: Tool = {
  name: "maps_reverse_geocode",
  description: "Convert coordinates into an address",
  inputSchema: {
    type: "object",
    properties: {
      latitude: { 
        type: "number", 
        description: "Latitude coordinate" 
      },
      longitude: { 
        type: "number", 
        description: "Longitude coordinate" 
      }
    },
    required: ["latitude", "longitude"]
  }
};

const SEARCH_PLACES_TOOL: Tool = {
  name: "maps_search_places",
  description: "Search for places using Google Places API",
  inputSchema: {
    type: "object",
    properties: {
      query: { 
        type: "string", 
        description: "Search query" 
      },
      location: {
        type: "object",
        properties: {
          latitude: { type: "number" },
          longitude: { type: "number" }
        },
        description: "Optional center point for the search"
      },
      radius: {
        type: "number",
        description: "Search radius in meters (max 50000)"
      }
    },
    required: ["query"]
  }
};

const PLACE_DETAILS_TOOL: Tool = {
  name: "maps_place_details",
  description: "Get detailed information about a specific place",
  inputSchema: {
    type: "object",
    properties: {
      place_id: {
        type: "string",
        description: "The place ID to get details for"
      }
    },
    required: ["place_id"]
  }
};

const DISTANCE_MATRIX_TOOL: Tool = {
  name: "maps_distance_matrix",
  description: "Calculate travel distance and time for multiple origins and destinations",
  inputSchema: {
    type: "object", 
    properties: {
      origins: {
        type: "array",
        items: { type: "string" },
        description: "Array of origin addresses or coordinates"
      },
      destinations: {
        type: "array", 
        items: { type: "string" },
        description: "Array of destination addresses or coordinates"
      },
      mode: {
        type: "string",
        description: "Travel mode (driving, walking, bicycling, transit)",
        enum: ["driving", "walking", "bicycling", "transit"]
      }
    },
    required: ["origins", "destinations"]
  }
};

const ELEVATION_TOOL: Tool = {
  name: "maps_elevation",
  description: "Get elevation data for locations on the earth",
  inputSchema: {
    type: "object",
    properties: {
      locations: {
        type: "array",
        items: {
          type: "object",
          properties: {
            latitude: { type: "number" },
            longitude: { type: "number" }
          },
          required: ["latitude", "longitude"]
        },
        description: "Array of locations to get elevation for"
      }
    },
    required: ["locations"]
  }
};

const DIRECTIONS_TOOL: Tool = {
  name: "maps_directions",
  description: "Get directions between two points",
  inputSchema: {
    type: "object",
    properties: {
      origin: { 
        type: "string", 
        description: "Starting point address or coordinates" 
      },
      destination: { 
        type: "string", 
        description: "Ending point address or coordinates" 
      },
      mode: {
        type: "string",
        description: "Travel mode (driving, walking, bicycling, transit)",
        enum: ["driving", "walking", "bicycling", "transit"]
      }
    },
    required: ["origin", "destination"]
  }
};

const MAPS_TOOLS = [
  GEOCODE_TOOL,
  REVERSE_GEOCODE_TOOL,
  SEARCH_PLACES_TOOL,
  PLACE_DETAILS_TOOL,
  DISTANCE_MATRIX_TOOL,
  ELEVATION_TOOL,
  DIRECTIONS_TOOL,
] as const;

// API handlers
async function handleGeocode(address: string) {
  const url = new URL("https://maps.googleapis.com/maps/api/geocode/json");
  url.searchParams.append("address", address);
  url.searchParams.append("key", GOOGLE_MAPS_API_KEY);

  const response = await fetch(url.toString());
  const data = await response.json() as GeocodeResponse;

  if (data.status !== "OK") {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Geocoding failed: ${data.error_message || data.status}`
        }],
        isError: true
      }
    };
  }

  return {
    toolResult: {
      content: [{
        type: "text",
        text: JSON.stringify({
          location: data.results[0].geometry.location,
          formatted_address: data.results[0].formatted_address,
          place_id: data.results[0].place_id
        }, null, 2)
      }],
      isError: false
    }
  };
}

async function handleReverseGeocode(latitude: number, longitude: number) {
  const url = new URL("https://maps.googleapis.com/maps/api/geocode/json");
  url.searchParams.append("latlng", `${latitude},${longitude}`);
  url.searchParams.append("key", GOOGLE_MAPS_API_KEY);

  const response = await fetch(url.toString());
  const data = await response.json() as GeocodeResponse;

  if (data.status !== "OK") {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Reverse geocoding failed: ${data.error_message || data.status}`
        }],
        isError: true
      }
    };
  }

  return {
    toolResult: {
      content: [{
        type: "text",
        text: JSON.stringify({
          formatted_address: data.results[0].formatted_address,
          place_id: data.results[0].place_id,
          address_components: data.results[0].address_components
        }, null, 2)
      }],
      isError: false
    }
  };
}

async function handlePlaceSearch(
  query: string,
  location?: { latitude: number; longitude: number },
  radius?: number
) {
  const url = new URL("https://maps.googleapis.com/maps/api/place/textsearch/json");
  url.searchParams.append("query", query);
  url.searchParams.append("key", GOOGLE_MAPS_API_KEY);

  if (location) {
    url.searchParams.append("location", `${location.latitude},${location.longitude}`);
  }
  if (radius) {
    url.searchParams.append("radius", radius.toString());
  }

  const response = await fetch(url.toString());
  const data = await response.json() as PlacesSearchResponse;

  if (data.status !== "OK") {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Place search failed: ${data.error_message || data.status}`
        }],
        isError: true
      }
    };
  }

  return {
    toolResult: {
      content: [{
        type: "text",
        text: JSON.stringify({
          places: data.results.map((place) => ({
            name: place.name,
            formatted_address: place.formatted_address,
            location: place.geometry.location,
            place_id: place.place_id,
            rating: place.rating,
            types: place.types
          }))
        }, null, 2)
      }],
      isError: false
    }
  };
}

async function handlePlaceDetails(place_id: string) {
  const url = new URL("https://maps.googleapis.com/maps/api/place/details/json");
  url.searchParams.append("place_id", place_id);
  url.searchParams.append("key", GOOGLE_MAPS_API_KEY);

  const response = await fetch(url.toString());
  const data = await response.json() as PlaceDetailsResponse;

  if (data.status !== "OK") {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Place details request failed: ${data.error_message || data.status}`
        }],
        isError: true
      }
    };
  }

  return {
    toolResult: {
      content: [{
        type: "text",
        text: JSON.stringify({
          name: data.result.name,
          formatted_address: data.result.formatted_address,
          location: data.result.geometry.location,
          formatted_phone_number: data.result.formatted_phone_number,
          website: data.result.website,
          rating: data.result.rating,
          reviews: data.result.reviews,
          opening_hours: data.result.opening_hours
        }, null, 2)
      }],
      isError: false
    }
  };
}
async function handleDistanceMatrix(
  origins: string[],
  destinations: string[],
  mode: "driving" | "walking" | "bicycling" | "transit" = "driving"
) {
  const url = new URL("https://maps.googleapis.com/maps/api/distancematrix/json");
  url.searchParams.append("origins", origins.join("|"));
  url.searchParams.append("destinations", destinations.join("|"));
  url.searchParams.append("mode", mode);
  url.searchParams.append("key", GOOGLE_MAPS_API_KEY);

  const response = await fetch(url.toString());
  const data = await response.json() as DistanceMatrixResponse;

  if (data.status !== "OK") {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Distance matrix request failed: ${data.error_message || data.status}`
        }],
        isError: true
      }
    };
  }

  return {
    toolResult: {
      content: [{
        type: "text",
        text: JSON.stringify({
          origin_addresses: data.origin_addresses,
          destination_addresses: data.destination_addresses,
          results: data.rows.map((row) => ({
            elements: row.elements.map((element) => ({
              status: element.status,
              duration: element.duration,
              distance: element.distance
            }))
          }))
        }, null, 2)
      }],
      isError: false
    }
  };
}

async function handleElevation(locations: Array<{ latitude: number; longitude: number }>) {
  const url = new URL("https://maps.googleapis.com/maps/api/elevation/json");
  const locationString = locations
    .map((loc) => `${loc.latitude},${loc.longitude}`)
    .join("|");
  url.searchParams.append("locations", locationString);
  url.searchParams.append("key", GOOGLE_MAPS_API_KEY);

  const response = await fetch(url.toString());
  const data = await response.json() as ElevationResponse;

  if (data.status !== "OK") {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Elevation request failed: ${data.error_message || data.status}`
        }],
        isError: true
      }
    };
  }

  return {
    toolResult: {
      content: [{
        type: "text",
        text: JSON.stringify({
          results: data.results.map((result) => ({
            elevation: result.elevation,
            location: result.location,
            resolution: result.resolution
          }))
        }, null, 2)
      }],
      isError: false
    }
  };
}

async function handleDirections(
  origin: string,
  destination: string,
  mode: "driving" | "walking" | "bicycling" | "transit" = "driving"
) {
  const url = new URL("https://maps.googleapis.com/maps/api/directions/json");
  url.searchParams.append("origin", origin);
  url.searchParams.append("destination", destination);
  url.searchParams.append("mode", mode);
  url.searchParams.append("key", GOOGLE_MAPS_API_KEY);

  const response = await fetch(url.toString());
  const data = await response.json() as DirectionsResponse;

  if (data.status !== "OK") {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Directions request failed: ${data.error_message || data.status}`
        }],
        isError: true
      }
    };
  }

  return {
    toolResult: {
      content: [{
        type: "text",
        text: JSON.stringify({
          routes: data.routes.map((route) => ({
            summary: route.summary,
            distance: route.legs[0].distance,
            duration: route.legs[0].duration,
            steps: route.legs[0].steps.map((step) => ({
              instructions: step.html_instructions,
              distance: step.distance,
              duration: step.duration,
              travel_mode: step.travel_mode
            }))
          }))
        }, null, 2)
      }],
      isError: false
    }
  };
}

// Server setup
const server = new Server(
  {
    name: "mcp-server/google-maps",
    version: "0.1.0",
  },
  {
    capabilities: {
      tools: {},
    },
  },
);

// Set up request handlers
server.setRequestHandler(ListToolsRequestSchema, async () => ({
  tools: MAPS_TOOLS,
}));

server.setRequestHandler(CallToolRequestSchema, async (request) => {
  try {
    switch (request.params.name) {
      case "maps_geocode": {
        const { address } = request.params.arguments as { address: string };
        return await handleGeocode(address);
      }
      
      case "maps_reverse_geocode": {
        const { latitude, longitude } = request.params.arguments as {
          latitude: number;
          longitude: number;
        };
        return await handleReverseGeocode(latitude, longitude);
      }
      
      case "maps_search_places": {
        const { query, location, radius } = request.params.arguments as {
          query: string;
          location?: { latitude: number; longitude: number };
          radius?: number;
        };
        return await handlePlaceSearch(query, location, radius);
      }
      
      case "maps_place_details": {
        const { place_id } = request.params.arguments as { place_id: string };
        return await handlePlaceDetails(place_id);
      }
      
      case "maps_distance_matrix": {
        const { origins, destinations, mode } = request.params.arguments as {
          origins: string[];
          destinations: string[];
          mode?: "driving" | "walking" | "bicycling" | "transit";
        };
        return await handleDistanceMatrix(origins, destinations, mode);
      }
      
      case "maps_elevation": {
        const { locations } = request.params.arguments as {
          locations: Array<{ latitude: number; longitude: number }>;
        };
        return await handleElevation(locations);
      }
      
      case "maps_directions": {
        const { origin, destination, mode } = request.params.arguments as {
          origin: string;
          destination: string;
          mode?: "driving" | "walking" | "bicycling" | "transit";
        };
        return await handleDirections(origin, destination, mode);
      }
      
      default:
        return {
          toolResult: {
            content: [{
              type: "text",
              text: `Unknown tool: ${request.params.name}`
            }],
            isError: true
          }
        };
    }
  } catch (error) {
    return {
      toolResult: {
        content: [{
          type: "text",
          text: `Error: ${error instanceof Error ? error.message : String(error)}`
        }],
        isError: true
      }
    };
  }
});

async function runServer() {
  const transport = new StdioServerTransport();
  await server.connect(transport);
  console.error("Google Maps MCP Server running on stdio");
}

runServer().catch((error) => {
  console.error("Fatal error running server:", error);
  process.exit(1);
});