Pantry Pal — an MCP server for Alexa+

Pantry Pal is a self-hosted Model Context Protocol server that lets Alexa+ manage a household pantry by voice: what you bought, what's about to expire, what you can cook tonight, and what to buy next.

• Transport: MCP Streamable HTTP (single POST /mcp endpoint, JSON responses)

• Spec: 2025-11-25 (also negotiates 2025-06-18 and 2025-03-26)

• Dependencies: none. Plain Node.js 18+ built-ins, so git clone && npm start just works.

Built for the Amazon Developer Hackathon, Alexa+ track.

Why this exists

Food waste is a household problem that voice is perfect for: your hands are full of groceries when you want to log them, and you ask "what should I cook?" while standing in the kitchen. Every tool returns a short sentence written to be read aloud, plus structuredContent for richer clients.

Related MCP server: ShelfLife MCP

Quick start

npm start                  # http://127.0.0.1:3000/mcp
npm test                   # 16 end-to-end tests against the live HTTP server

Environment variables:

Tools

Read-only tools carry readOnlyHint annotations. Invalid input comes back as a tool result with isError: true (so the model can correct itself and ask you), while protocol problems return proper JSON-RPC errors.

Try it without Alexa

npm start &

curl -s localhost:3000/mcp -H 'Content-Type: application/json' -H 'Accept: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-11-25","capabilities":{},"clientInfo":{"name":"curl","version":"0"}}}'

curl -s localhost:3000/mcp -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"add_item","arguments":{"name":"eggs","quantity":6,"expires_in_days":2}}}'

You can also point the official MCP Inspector at http://127.0.0.1:3000/mcp (Streamable HTTP).

Connecting to Alexa+

Alexa+ needs to reach your server over public HTTPS, so expose it first:

1. Run the server with a token: PANTRY_TOKEN=$(openssl rand -hex 24) HOST=0.0.0.0 npm start

2. Put it behind TLS: a tunnel (cloudflared tunnel --url http://localhost:3000, ngrok) for the demo, or a reverse proxy / AWS (ALB, App Runner, ECS) for something durable.

3. Register https://<your-host>/mcp and the bearer token as the MCP integration in the Alexa+ developer console for your account.

I haven't been able to verify step 3 against a live Alexa+ Preview account from my build environment, so the exact console labels may differ from the above; the endpoint itself is a standard MCP Streamable HTTP server and is verified by the test suite.

Design notes

• Speakable output. Responses are short, avoid lists of more than a handful of items, and end with a follow-up question when a decision is needed ("Want me to add it to your shopping list?").

• Spec compliance. initialize negotiates the protocol version and issues an Mcp-Session-Id; notifications get 202; GET returns 405 (no standalone SSE stream); DELETE ends a session; JSON-RPC batching is rejected as of 2025-06-18; MCP-Protocol-Version is validated; Origin is checked to block DNS-rebinding.

• Safe by default. Binds to localhost, optional bearer auth, 256 KB body cap, atomic file writes.

• Single household. State is one JSON file. Multi-user accounts and OAuth are the obvious next step.

Layout

server.js   MCP server + tools (the whole thing, ~350 lines)
test.js     end-to-end tests (node:test)

License

MIT, see LICENSE.