irm-kmi-mcp

An MCP server exposing official Belgian weather data from the Royal Meteorological Institute of Belgium (IRM/KMI): observed conditions, daily and hourly forecasts, and weather warnings, for MCP clients such as Claude, Hermes or Openclaw.

"What's the weather in Namur?"            →  current_conditions("Namur")
"Forecast for Oostende, 5 days, in Dutch" →  daily_forecast("Oostende", days=5, language="nl")
"Any warnings in Belgium right now?"      →  warnings()

Features

• Observed conditions: temperature, condition, UV index, sunrise/sunset from the nearest IRM weather station.
• Daily forecast (1–8 days): min/max temperature, condition, wind, precipitation, plus the official IRM text bulletin in fr/nl/en/de.
• Hourly forecast (1–49 h): temperature, precipitation, pressure, wind and gusts.
• Official weather warnings: yellow/orange/red alerts, either for a single municipality (with level and validity period) or for the whole country.
• Municipality resolution by name: "Namur", "Bruxelles", "Oostende", … resolved through the IRM's own city search.
• Caching: weather data is cached for 10 minutes, city lookups for 24 hours.

Tools

Data source & disclaimer

⚠️ Unofficial. This project is not affiliated with the IRM/KMI. It works by calling the same backend service that powers the official IRM mobile app. That service was never meant for public use: it is undocumented and it can break or disappear without notice. Please use it for personal, low-frequency purposes only.

The API surface was reverse-engineered and documented by Jules Dejaeghere in jdejaegh/irm-kmi-api and jdejaegh/irm-kmi-ha. Many thanks for the groundwork. This project is not affiliated with, sponsored or endorsed by the IRM/KMI.

Installation

git clone https://github.com/kthys/irm-kmi-mcp.git
cd irm-kmi-mcp
python3 -m venv .venv
.venv/bin/pip install -e .

Usage

Run the server (stdio transport):

.venv/bin/irm-kmi-mcp
# or
.venv/bin/python -m irm_kmi_mcp

Claude Desktop

{
  "mcpServers": {
    "irm-kmi-mcp": {
      "command": "/absolute/path/to/irm-kmi-mcp/.venv/bin/irm-kmi-mcp"
    }
  }
}

Hermes Agent

# config.yaml
mcp_servers:
  irm-kmi-mcp:
    command: "/absolute/path/to/irm-kmi-mcp/.venv/bin/irm-kmi-mcp"
    enabled: true

No API keys or configuration required. The daily request key is derived automatically.

Configuration

• IRM_LANG: default language for official texts (bulletins, warning texts, day names, wind directions): fr, nl, en or de. Unset or invalid values fall back to English. Read once at server startup; set it before launching the server.

Development

.venv/bin/pip install -e ".[dev]"
.venv/bin/pytest
.venv/bin/ruff check .

Tests run against recorded API responses (tests/fixtures/) with a mocked HTTP transport, so no network access is required. Re-record fixtures after upstream API changes.