No key, no account, one binary — which makes it about the cheapest thing to add to a client and the easiest to remove. All four calls are coordinate-driven, so the pattern is search the place first and then ask about it; the forecast tops out at 16 days and the historical tool wants an explicit date range.
An MCP server over the free OpenMeteo weather API. Four tools cover the shape of most weather questions: what it is doing now, what it will do, what it did, and where exactly you mean. Coordinates drive everything, and the search tool is how a place name becomes coordinates.
- Current conditions for a latitude and longitude — temperature and feels-like, humidity, precipitation, wind speed, direction and gusts, pressure, cloud cover, a condition description and a day/night flag — `get_current_weather`
- Forecast for up to 16 days with daily highs and lows, conditions, precipitation, maximum wind, sunrise and sunset, UV index and daylight duration — `get_weather_forecast`
- Historical daily data between a `start_date` and an `end_date`: temperature min, max and mean, precipitation totals, wind, and summary statistics for the period — `get_historical_weather`
- Place-name lookup returning coordinates, country, administrative region, timezone and population where available — `search_locations`
No API key and no account — OpenMeteo is free to call. Download the prebuilt binary for macOS on Apple Silicon or Intel, Linux or Windows from the releases page, or build from source with Rust 1.87 or newer and `cargo build --release`. Point the client's `command` at the binary; that is the whole configuration. `RUST_LOG` controls logging verbosity, and outbound requests carry a 30-second timeout.