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WeatherMCP serverFirst audited Nov 13, 2026

io.github.cyanheads/open-meteo-mcp-server

Global weather via Open-Meteo: forecast, historical, marine, air quality, geocoding, elevation.The vendor's description, from its MCP Registry listing.

Passed public checksAudited Nov 13, 2026

Every public check ran and passed. Public audit: we connect as an AI client would, list the tools and check what they say. We do not run them. How we audit

Does it work?
YesConnected in 343 ms.
Sign-up?
None neededIt answered without any account or key.
Can it change things?
No, read-onlyAll 11 tools say they only read.
Endpointhttps://open-meteo.caseyjhand.com/mcp

Source code Streamable HTTP · protocol 2025-11-25 · server version 0.6.0

What we checked, the evidence, and the tools it offers.

What we checked

Security

  • Passed: Connections are encrypted (HTTPS).

  • Passed: No hidden instructions found in tool text.

Safety labels

  • Passed: Every tool says whether it only reads or can change things.

Tools

  • Note: Some tool text is long, so it uses more of the AI's working memory.

    • server instructions (6,928 characters)
  • Passed: 11 tools listed.

  • Passed: Every tool describes its inputs with a valid schema.

Protocol

  • Passed: The MCP handshake works (Streamable HTTP).

  • Passed: Protocol version 2025-11-25 (latest).

  • Passed: Unknown requests are refused.

Connection

  • Passed: The server responds.

Tools (11)

As the server describes them. The labels are the server's own: it says whether each tool only reads or can change things.

  • openmeteo_search_locationsResolve a place name to ranked coordinate matches with country, region, elevation, timezone, and population. Required prerequisite for name-based queries — all weather tools take latitude/longitude,…Read-only
  • openmeteo_get_elevationTerrain elevation from the Copernicus Digital Elevation Model (~90m resolution) for one or more coordinate pairs. Accepts up to 1,000 pairs and samples the first 100 in one upstream request; when mor…Read-only
  • openmeteo_get_forecastWeather forecast for coordinates: hourly and/or daily variables for up to 16 days ahead, with optional past_days (up to 92) for recent history. Use past_days instead of openmeteo_get_historical for d…Read-only
  • openmeteo_get_historicalHistorical weather from the Open-Meteo reanalysis archive (1940–present). Requires start_date and end_date (ISO 8601 date, e.g., "2024-07-01"). With models omitted the archive answers from Best Match…Read-only
  • openmeteo_get_marineMarine wave and ocean conditions for a coastal or ocean coordinate: wave height, wave period, wave direction, wind-wave height, swell height, sea-surface temperature. Forecast horizon up to 8 days, w…Read-only
  • openmeteo_get_air_qualityModeled CAMS (Copernicus Atmosphere Monitoring Service) air quality: PM2.5, PM10, nitrogen dioxide, sulphur dioxide, ozone, carbon monoxide, dust, pollen, and European/US AQI indices. This is modeled…Read-only
  • openmeteo_get_ensembleProbabilistic ensemble weather forecast — up to 64 ensemble members, up to 35 days ahead with optional past_days (0–92). Most models end within 16 days; a model's columns are null past its horizon, a…Read-only
  • openmeteo_get_floodGloFAS (Global Flood Awareness System) daily river discharge (m³/s) from the GloFAS 0.05° grid cell nearest the given coordinates — no river ID needed. The response's latitude and longitude name that…Read-only
  • openmeteo_get_climateLong-range climate projections from bias-corrected daily CMIP6 models, covering 1950-01-01 to 2050-12-31 at any coordinate. Answers "what will conditions look like through 2050?" — the future-project…Read-only
  • openmeteo_dataframe_queryRun a read-only SQL SELECT against tables staged on a DataCanvas by openmeteo_get_forecast, openmeteo_get_historical, openmeteo_get_marine, openmeteo_get_air_quality, openmeteo_get_ensemble, openmete…Read-only
  • openmeteo_dataframe_describeList the tables and their columns on a DataCanvas staged by openmeteo_get_forecast, openmeteo_get_historical, openmeteo_get_marine, openmeteo_get_air_quality, openmeteo_get_ensemble, openmeteo_get_fl…Read-only

Audit history

  1. Nov 13Passed

What we sent

Every request in this audit, with the answer and how long it took. We never send credentials and never call a tool.

RequestAnswerTime
initializeHTTP 200343 ms
initializedHTTP 202276 ms
tools/listHTTP 200184 ms
resources/listHTTP 200112 ms
prompts/listHTTP 200109 ms
unknown-methodHTTP 200125 ms

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