jarvis-mcp-server

Standalone MCP server(s) for Jarvis. It currently hosts a time server (in the time_server/ package) that reports the current local time for a city, and is structured to grow more tool domains over time — each added as its own package alongside time_server/.

Unlike a stdio MCP server (which a client launches as a subprocess), it runs as an independent network process over Streamable HTTP, so it has its own lifecycle and can be reached by the MCP Inspector, a CLI client, or a Cloud Run deployment.

Tools

Tool	Args	Returns
get_current_time	city: str	Current local time + timezone for the city
echo	text: str	The input unchanged (connectivity smoke-test)

get_current_time is a two-hop pipeline: Open-Meteo geocoding (city → lat/lon) → TimeAPI.io (lat/lon → local time). Both APIs are free and need no key. If the network is unavailable it falls back to the system UTC clock, so a call never hard-fails.

Run locally

python -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt
python -m time_server.server          # serves http://0.0.0.0:8080/mcp

Configuration (env vars)

Var	Default	Purpose
HOST	0.0.0.0	Bind address
PORT	8080	Bind port (Cloud Run injects this)
TRANSPORT	streamable-http	streamable-http | sse | stdio
MCP_API_KEY	(unset)	If set, every request (except /healthz) must send a matching X-API-Key. Unset → open server (local/Inspector only).
LOG_LEVEL	INFO	Server log verbosity

Security

• Auth: set MCP_API_KEY; clients must send it as the X-API-Key header. Comparison is constant-time and the key is never logged. Leaving it unset logs a loud warning and runs the server open — fine for local Inspector testing, never for a public deployment.
• Health: GET /healthz is unauthenticated (for Cloud Run / curl probes).

Test with the MCP Inspector

In a second terminal (server still running):

npx @modelcontextprotocol/inspector

In the Inspector UI:

1. Transport Type: Streamable HTTP
2. URL: http://localhost:8080/mcp
3. Connect → open the Tools tab → run get_current_time with city = London.

Automated checks

python tests/smoke_http.py      # end-to-end over Streamable HTTP (server must be up)
pytest -q                       # offline unit tests (no network, no server)

Deployment

See DEPLOY.md for the Cloud Run build/deploy commands, secret setup, and how scaling / cold starts work.

Roadmap

• [x] Standalone Streamable HTTP server + two tools
• [x] Local test via MCP Inspector
• [x] JarvisCLI client wired (auth-aware, degrades cleanly when down/unauthorized)
• [x] API-key auth middleware (pure-ASGI, constant-time, /healthz exempt)
• [x] Dockerfile (slim, non-root, port 8080)
• [x] Cloud Run deploy guide