Weather MCP Server

import { z } from 'zod'; import { getAlerts, getForecast } from './weather.js'; // MCP JSON-RPC protocol implementation export interface MCPRequest { jsonrpc: '2.0'; id?: string | number; method: string; params?: any; } export interface MCPResponse { jsonrpc: '2.0'; id?: string | number; result?: any; error?: { code: number; message: string; data?: any; }; } export interface MCPNotification { jsonrpc: '2.0'; method: string; params?: any; } // MCP Protocol Handler export class MCPProtocolHandler { async handleRequest(request: MCPRequest): Promise<MCPResponse> { const { id, method, params } = request; try { switch (method) { case 'initialize': return { jsonrpc: '2.0', id, result: { protocolVersion: '2024-11-05', capabilities: { tools: {} }, serverInfo: { name: 'weather', version: '1.0.0' } } }; case 'tools/list': return { jsonrpc: '2.0', id, result: { tools: [ { name: 'get_alerts', description: 'Get weather alerts for a state', inputSchema: { type: 'object', properties: { state: { type: 'string', minLength: 2, maxLength: 2, description: 'Two-letter state code (e.g. CA, NY)' } }, required: ['state'] } }, { name: 'get_forecast', description: 'Get weather forecast for a location', inputSchema: { type: 'object', properties: { latitude: { type: 'number', minimum: -90, maximum: 90, description: 'Latitude of the location' }, longitude: { type: 'number', minimum: -180, maximum: 180, description: 'Longitude of the location' } }, required: ['latitude', 'longitude'] } } ] } }; case 'tools/call': const { name, arguments: args } = params; if (name === 'get_alerts') { const result = await getAlerts(args.state); return { jsonrpc: '2.0', id, result }; } if (name === 'get_forecast') { const result = await getForecast(args.latitude, args.longitude); return { jsonrpc: '2.0', id, result }; } return { jsonrpc: '2.0', id, error: { code: -32601, message: `Unknown tool: ${name}` } }; default: return { jsonrpc: '2.0', id, error: { code: -32601, message: `Method not found: ${method}` } }; } } catch (error) { return { jsonrpc: '2.0', id, error: { code: -32603, message: 'Internal error', data: error instanceof Error ? error.message : 'Unknown error' } }; } } }