Map Canvas MCP

An embedded interactive map for MCP Apps hosts such as ChatGPT. The Worker returns map data plus a stable UI loader. Each tool result selects a content-addressed Leaflet bundle served from Cloudflare Static Assets, so UI updates do not require refreshing unchanged tool metadata. The user's browser fetches visible OpenStreetMap tiles directly from the standard tile servers.

Production endpoint

https://map-canvas.android-mxdiego9.workers.dev/mcp

The endpoint is public and does not require authentication.

Local development

npm install
npm run check
npm run dev

npm run check type-checks the Worker and runs MCP smoke tests for initialization, tool discovery, tool execution, and widget resource loading.

The local MCP endpoint is http://localhost:8787/mcp. Test it with the MCP Inspector:

npx @modelcontextprotocol/inspector@latest

Deploy

Deploy from a terminal:

npm run deploy

No API key is required. Do not add secrets to source or wrangler.jsonc; use Cloudflare secrets if authentication is added later.

Deploy with GitHub Actions

The included workflow deploys on every push to main, then runs the production MCP smoke test against the public endpoint. It can also be run manually from the Actions tab. Add these repository Actions secrets first:

• CLOUDFLARE_API_TOKEN: a token scoped to edit Workers in the target account
• CLOUDFLARE_ACCOUNT_ID: the target Cloudflare account ID

The values stay in GitHub Actions secrets and must not be committed to the repository.

Tool

show_map accepts 1–50 places with decimal latitude/longitude coordinates. Simple callers can still use connectPlaces; travel itineraries can also add:

• day/date and time labels with day filtering
• categories and confirmed/planned/tentative status
• transport legs for walking, car, taxi, bus, rail, ferry, and flights
• schematic straight connections or actual route geometry
• verified place links, with a Google Maps coordinate link as the fallback

The widget uses numbered, category-colored markers, an itinerary panel, a reset-view action, and optional fullscreen presentation in ChatGPT. Schematic legs are dashed and explicitly labeled so they are not mistaken for turn-by-turn navigation.

Map data © OpenStreetMap contributors.