WeatherTool.ts•4.09 kB
import { z } from "zod";
import axios from "axios";
import type { TextContent } from "@modelcontextprotocol/sdk/types.js";
import type { RequestHandlerExtra } from "@modelcontextprotocol/sdk/shared/protocol.js";
// Zod schemas for validation
export const inputShape = {
location: z.string().min(1, "Location must be at least 1 character"),
units: z.enum(["imperial", "metric"]).default("metric").optional().describe("Temperature unit system")
};
export const inputSchema = z.object(inputShape).describe("Get hourly weather forecast");
// JSON schema for tool registration (OpenAI-compatible)
export const inputJsonSchema = {
type: "object",
description: "Parameters for the hourly weather-forecast tool",
properties: {
location: {
type: "string",
description: "The location to fetch the 12-hour forecast for",
},
units: {
type: "string",
description: "Temperature unit system (metric for Celsius, imperial for Fahrenheit). Default is metric.",
enum: ["metric", "imperial"]
}
},
required: ["location"],
additionalProperties: false,
};
// Handler function remains unchanged
export async function handler(
args: { [x: string]: any },
extra: RequestHandlerExtra<any, any>
): Promise<{ content: TextContent[] }> {
// Validate args using the Zod schema
let validatedArgs: z.infer<typeof inputSchema>;
try {
validatedArgs = inputSchema.parse(args);
} catch (error) {
if (error instanceof z.ZodError) {
const errorMessages = error.errors
.map((e) => `${e.path.join('.')}: ${e.message}`)
.join(', ');
return { content: [{ type: 'text', text: `Invalid input: ${errorMessages}` }] };
}
return { content: [{ type: 'text', text: 'An unexpected error occurred during input validation.' }] };
}
const { location, units = "metric" } = validatedArgs;
const apiKey = process.env.ACCUWEATHER_API_KEY;
if (!apiKey) {
return { content: [{ type: 'text', text: 'Error: AccuWeather API key not configured' }] };
}
try {
// Step 1: Get location key
const locationUrl = `https://dataservice.accuweather.com/locations/v1/cities/search?apikey=${apiKey}&q=${encodeURIComponent(location)}`;
const locationResp = await axios.get(locationUrl);
if (!locationResp.data || locationResp.data.length === 0) {
return { content: [{ type: 'text', text: `No location found for: ${location}` }] };
}
const locationKey = locationResp.data[0].Key;
// Step 2: Get forecast with location key
const forecastUrl = `https://dataservice.accuweather.com/forecasts/v1/hourly/12hour/${locationKey}?apikey=${apiKey}&metric=${units === "metric" ? "true" : "false"}`;
const forecastResp = await axios.get(forecastUrl);
const data = forecastResp.data;
if (!data || !Array.isArray(data) || data.length === 0) {
return {
content: [{ type: 'text', text: `No weather data available for location: ${location}` }]
};
}
const unitSymbol = units === "metric" ? "C" : "F";
const content: TextContent[] = data.map((hour: any) => ({
type: 'text',
text: `${hour.DateTime}: ${hour.Temperature.Value}°${unitSymbol}, ${hour.IconPhrase}`,
}));
return { content };
} catch (error) {
console.error("WeatherTool handler error:", error);
let errorMessage = "An error occurred while fetching weather data.";
if (axios.isAxiosError(error)) {
if (error.response?.status === 401) {
errorMessage = "Invalid AccuWeather API key. Please check your credentials.";
} else if (error.response?.status === 404) {
errorMessage = `Location not found: ${location}`;
} else if (error.response) {
errorMessage = `AccuWeather API error (${error.response.status}): ${error.response.data?.Message || error.message}`;
} else if (error.request) {
errorMessage = "Network error: Unable to connect to AccuWeather API.";
}
}
return { content: [{ type: 'text', text: errorMessage }] };
}
}
export default { inputShape, inputSchema, inputJsonSchema, handler };