mcp-nordic

Instructions

Implementation Reference

• src/servers/finnish-weather.js:204-244 (handler)

  Registration and handler implementation for the 'fi_compare_weather' MCP tool. It fetches weather data for two locations using 'openMeteoFetch' and returns a side-by-side comparison.

  server.tool(
    "fi_compare_weather",
    "Compare current weather between two Finnish locations side by side.",
    {
      location1: z.string().describe("First location (city name or coordinates)"),
      location2: z.string().describe("Second location"),
    },
    async ({ location1, location2 }) => {
      try {
        const [loc1, loc2] = await Promise.all([getLocation(location1), getLocation(location2)]);
        const [data1, data2] = await Promise.all([
          openMeteoFetch({
            latitude: loc1.lat, longitude: loc1.lon,
            current: "temperature_2m,apparent_temperature,precipitation,snowfall,weather_code,wind_speed_10m,cloud_cover",
          }),
          openMeteoFetch({
            latitude: loc2.lat, longitude: loc2.lon,
            current: "temperature_2m,apparent_temperature,precipitation,snowfall,weather_code,wind_speed_10m,cloud_cover",
          }),
        ]);
        const c1 = data1.current, c2 = data2.current;
        const wx1 = WMO_CODES[c1.weather_code] || "", wx2 = WMO_CODES[c2.weather_code] || "";
        const lines = [
          `## Weather Comparison\n`,
          `| | ${loc1.name} | ${loc2.name} |`,
          `|---|---|---|`,
          `| **Conditions** | ${wx1} | ${wx2} |`,
          `| **Temperature** | ${c1.temperature_2m}°C | ${c2.temperature_2m}°C |`,
          `| **Feels like** | ${c1.apparent_temperature}°C | ${c2.apparent_temperature}°C |`,
          `| **Wind** | ${c1.wind_speed_10m} km/h | ${c2.wind_speed_10m} km/h |`,
          `| **Cloud cover** | ${c1.cloud_cover}% | ${c2.cloud_cover}% |`,
          `| **Precipitation** | ${c1.precipitation} mm | ${c2.precipitation} mm |`,
          c1.snowfall > 0 || c2.snowfall > 0 ? `| **Snowfall** | ${c1.snowfall} cm | ${c2.snowfall} cm |` : null,
          `\n*Open-Meteo*`,
        ].filter(Boolean);
        return { content: [{ type: "text", text: lines.join("\n") }] };
      } catch (err) {
        return { content: [{ type: "text", text: `Error: ${err.message}` }], isError: true };
      }
    }
  );