# Example: Interactive Map
Interactive 3D globe viewer using CesiumJS with OpenStreetMap tiles. Demonstrates geocoding integration and full MCP App capabilities.
## MCP Client Configuration
Add to your MCP client configuration (stdio transport):
```json
{
"mcpServers": {
"map": {
"command": "npx",
"args": [
"-y",
"--silent",
"--registry=https://registry.npmjs.org/",
"@modelcontextprotocol/server-map",
"--stdio"
]
}
}
}
```
### Local Development
To test local modifications, use this configuration (replace `~/code/ext-apps` with your clone path):
```json
{
"mcpServers": {
"map": {
"command": "bash",
"args": [
"-c",
"cd ~/code/ext-apps/examples/map-server && npm run build >&2 && node dist/index.js --stdio"
]
}
}
}
```
## Features
- **3D Globe Rendering**: Interactive CesiumJS globe with rotation, zoom, and 3D perspective
- **Geocoding**: Search for places using OpenStreetMap Nominatim (no API key required)
- **OpenStreetMap Tiles**: Uses free OSM tile server (no Cesium Ion token needed)
- **Dynamic Loading**: CesiumJS loaded from CDN at runtime for smaller bundle size
## Running
1. Install dependencies:
```bash
npm install
```
2. Build and start the server:
```bash
npm run start:http # for Streamable HTTP transport
# OR
npm run start:stdio # for stdio transport
```
3. View using the [`basic-host`](https://github.com/modelcontextprotocol/ext-apps/tree/main/examples/basic-host) example or another MCP Apps-compatible host.
## Tools
### `geocode`
Search for places by name or address. Returns coordinates and bounding boxes.
```json
{
"query": "Eiffel Tower"
}
```
Returns up to 5 matches with lat/lon coordinates and bounding boxes.
### `show-map`
Display the 3D globe zoomed to a bounding box.
```json
{
"west": 2.29,
"south": 48.85,
"east": 2.3,
"north": 48.86,
"label": "Eiffel Tower"
}
```
Defaults to London if no coordinates provided.
## Architecture
### Server (`server.ts`)
Exposes two tools:
- `geocode` - Queries OpenStreetMap Nominatim API with rate limiting
- `show-map` - Renders the CesiumJS globe UI at a specified location
Configures Content Security Policy to allow fetching tiles from OSM and Cesium CDN.
### App (`src/mcp-app.ts`)
Vanilla TypeScript app that:
- Dynamically loads CesiumJS from CDN
- Initializes globe with OpenStreetMap imagery (no Ion token)
- Receives tool inputs via the MCP App SDK
- Handles camera navigation to specified bounding boxes
## Key Files
- [`server.ts`](server.ts) - MCP server with geocode and show-map tools
- [`mcp-app.html`](mcp-app.html) / [`src/mcp-app.ts`](src/mcp-app.ts) - CesiumJS globe UI
- [`server-utils.ts`](server-utils.ts) - HTTP server utilities
## Notes
- Rate limiting is applied to Nominatim requests (1 request per second per their usage policy)
- The globe works in sandboxed iframes with appropriate CSP configuration
- No external API keys required - uses only open data sources
