mcp-nordic

Instructions

Implementation Reference

• src/servers/swedish-weather.js:159-195 (handler)

  Implementation and registration of the 'se_weather_forecast' tool.

  server.tool(
    "se_weather_forecast",
    "Get weather forecast for a location in Sweden using SMHI. Returns hourly data for the next N hours.",
    {
      location: z.string().describe("Swedish city name or lat,lon coordinates"),
      hours: z.number().min(1).max(72).optional().describe("Hours ahead (default 24, max 72)"),
    },
    async ({ location, hours }) => {
      try {
        const loc = await getLocation(location);
        const data = await fetchForecast(loc.lat, loc.lon);
        const maxHours = hours || 24;
        const now = Date.now();
        const cutoff = now + maxHours * 3600000;
  
        const lines = [`## ${loc.name} — ${maxHours}h Forecast\n`];
        for (const entry of data.timeSeries) {
          const t = new Date(entry.validTime);
          if (t.getTime() > cutoff) break;
          if (t.getTime() < now - 3600000) continue;
  
          const time = t.toLocaleString("sv-SE", { timeZone: "Europe/Stockholm", weekday: "short", day: "numeric", month: "short", hour: "2-digit", minute: "2-digit" });
          const p = entry.parameters;
          const temp = getParam(p, "t");
          const wind = getParam(p, "ws");
          const wsymb = getParam(p, "Wsymb2");
          const precip = getParam(p, "pmean");
  
          lines.push(`**${time}:** ${temp}°C, ${WSYMB2[wsymb] || ""}, wind ${wind} m/s${precip > 0 ? `, ${precip} mm/h` : ""}`);
        }
        lines.push(`\n*SMHI Open Data*`);
        return { content: [{ type: "text", text: lines.join("\n") }] };
      } catch (err) {
        return { content: [{ type: "text", text: `Error: ${err.message}` }], isError: true };
      }
    }
  );