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Your MCP server is now running at `http://localhost:8788/sse`

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---

import { McpAgent } from "agents/mcp";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { z } from "zod";

export class MyMCP extends McpAgent<Env> {
  server = new McpServer({
    name: "My MCP Server",
    version: "1.0.0"
  });

  async init() {
    // Register tools here
    this.server.tool(
      "tool_name",
      "Tool description",
      { param: z.string() },
      async ({ param }) => ({
        content: [{ type: "text", text: "Result" }]
      })
    );
  }
}

this.server.tool(
  "tool_name",           // Tool identifier
  "Tool description",    // What it does (for LLM)
  {                      // Parameters (Zod schema)
    param1: z.string().describe("Parameter description"),
    param2: z.number().optional()
  },
  async ({ param1, param2 }) => {  // Handler
    // Your logic here
    return {
      content: [{ type: "text", text: "Result" }]
    };
  }
);

MyMCP.serveSSE("/sse").fetch(request, env, ctx)

MyMCP.serve("/mcp").fetch(request, env, ctx)

export default {
  fetch(request: Request, env: Env, ctx: ExecutionContext) {
    const { pathname } = new URL(request.url);

    if (pathname.startsWith("/sse")) {
      return MyMCP.serveSSE("/sse").fetch(request, env, ctx);
    }
    if (pathname.startsWith("/mcp")) {
      return MyMCP.serve("/mcp").fetch(request, env, ctx);
    }

    return new Response("Not Found", { status: 404 });
  }
};

import { JWTVerifier } from "agents/mcp";

const verifier = new JWTVerifier({
  secret: env.JWT_SECRET,
  issuer: "your-auth-server"
});

// Validate token before serving MCP requests

import { OAuthProvider, GitHubHandler } from "@cloudflare/workers-oauth-provider";

export default new OAuthProvider({
  authorizeEndpoint: "/authorize",
  tokenEndpoint: "/token",
  clientRegistrationEndpoint: "/register",

  defaultHandler: new GitHubHandler({
    clientId: (env) => env.GITHUB_CLIENT_ID,
    clientSecret: (env) => env.GITHUB_CLIENT_SECRET,
    scopes: ["repo", "user:email"],

    context: async (accessToken) => {
      // Fetch user info from GitHub
      const octokit = new Octokit({ auth: accessToken });
      const { data: user } = await octokit.rest.users.getAuthenticated();

      return {
        login: user.login,
        email: user.email,
        accessToken
      };
    }
  }),

  kv: (env) => env.OAUTH_KV,
  apiHandlers: {
    "/sse": MyMCP.serveSSE("/sse"),
    "/mcp": MyMCP.serve("/mcp")
  },

  allowConsentScreen: true,
  allowDynamicClientRegistration: true
});

{
  "kv_namespaces": [
    { "binding": "OAUTH_KV", "id": "YOUR_KV_ID" }
  ]
}

await this.state.storage.put("key", "value");
await this.state.storage.put("user_prefs", { theme: "dark" });

const value = await this.state.storage.get<string>("key");
const prefs = await this.state.storage.get<object>("user_prefs");

const allKeys = await this.state.storage.list();

await this.state.storage.delete("key");

{
  "durable_objects": {
    "bindings": [
      {
        "name": "MY_MCP",
        "class_name": "MyMCP",
        "script_name": "my-mcp-server"
      }
    ]
  },

  "migrations": [
    { "tag": "v1", "new_classes": ["MyMCP"] }
  ]
}

webSocket.serializeAttachment({
  userId: "123",
  sessionId: "abc",
  connectedAt: Date.now()
});

const metadata = webSocket.deserializeAttachment();
console.log(metadata.userId); // "123"

// ❌ DON'T: In-memory state lost on hibernation
this.userId = "123";

// ✅ DO: Use storage API
await this.state.storage.put("userId", "123");

export default {
  fetch(request: Request, env: Env, ctx: ExecutionContext): Response | Promise<Response> {
    // Handle request
    return new Response("Hello");
  }
};

export class MyMCP extends McpAgent<Env> {
  constructor(state: DurableObjectState, env: Env) {
    super(state, env);
  }

  // Your methods here
}

{
  "kv_namespaces": [{ "binding": "MY_KV", "id": "..." }],
  "durable_objects": {
    "bindings": [{ "name": "MY_DO", "class_name": "MyDO" }]
  },
  "r2_buckets": [{ "binding": "MY_BUCKET", "bucket_name": "..." }]
}

env.MY_KV.get("key");
env.MY_DO.idFromName("session-123").getStub(env);
env.MY_BUCKET.get("file.txt");

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**Access at**: `http://localhost:8788/sse`

npx @modelcontextprotocol/inspector@latest

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**Your server is live at**:

undefined

{
  "mcpServers": {
    "my-mcp": {
      "url": "https://my-mcp-server.your-account.workers.dev/sse"
    }
  }
}

{
  "mcpServers": {
    "my-mcp": {
      "url": "https://my-mcp-oauth.your-account.workers.dev/sse",
      "auth": {
        "type": "oauth",
        "authorizationUrl": "https://my-mcp-oauth.your-account.workers.dev/authorize",
        "tokenUrl": "https://my-mcp-oauth.your-account.workers.dev/token"
      }
    }
  }
}

this.server.tool(
  "search_wikipedia",
  "Search Wikipedia for a topic",
  { query: z.string() },
  async ({ query }) => {
    const response = await fetch(
      `https://en.wikipedia.org/api/rest_v1/page/summary/${encodeURIComponent(query)}`
    );
    const data = await response.json();

    return {
      content: [{
        type: "text",
        text: data.extract
      }]
    };
  }
);

this.server.tool(
  "get_user",
  "Get user details from database",
  { userId: z.string() },
  async ({ userId }) => {
    // Query Durable Objects storage
    const user = await this.state.storage.get<User>(`user:${userId}`);

    // Or query D1 database
    const result = await env.DB.prepare(
      "SELECT * FROM users WHERE id = ?"
    ).bind(userId).first();

    return {
      content: [{
        type: "text",
        text: JSON.stringify(user || result, null, 2)
      }]
    };
  }
);

// Store result from first tool
await this.state.storage.put("last_search", result);

// Second tool reads it
const lastSearch = await this.state.storage.get("last_search");

this.server.tool(
  "get_weather",
  "Get weather (cached 5 minutes)",
  { city: z.string() },
  async ({ city }) => {
    const cacheKey = `weather:${city}`;
    const cached = await this.state.storage.get<CachedWeather>(cacheKey);

    // Check cache freshness
    if (cached && Date.now() - cached.timestamp < 5 * 60 * 1000) {
      return {
        content: [{ type: "text", text: cached.data }]
      };
    }

    // Fetch fresh data
    const weather = await fetchWeatherAPI(city);

    // Cache it
    await this.state.storage.put(cacheKey, {
      data: weather,
      timestamp: Date.now()
    });

    return {
      content: [{ type: "text", text: weather }]
    };
  }
);

async rateLimit(key: string, maxRequests: number, windowMs: number): Promise<boolean> {
  const now = Date.now();
  const requests = await this.state.storage.get<number[]>(`ratelimit:${key}`) || [];

  // Remove old requests outside window
  const recentRequests = requests.filter(ts => now - ts < windowMs);

  if (recentRequests.length >= maxRequests) {
    return false; // Rate limited
  }

  // Add this request
  recentRequests.push(now);
  await this.state.storage.put(`ratelimit:${key}`, recentRequests);

  return true; // Allowed
}

// Use in tool
if (!await this.rateLimit(userId, 10, 60 * 1000)) {
  return {
    content: [{ type: "text", text: "Rate limit exceeded (10 requests/minute)" }],
    isError: true
  };
}

export class MyMCP extends McpAgent { ... }  // ✅ Must export
export default { fetch() { ... } }

{
  "migrations": [
    { "tag": "v1", "new_classes": ["MyMCP"] }
  ]
}

openssl rand -base64 32

---

z.string().transform(val => parseInt(val, 10))

{
  "name": "my-mcp-server",
  "main": "src/index.ts",
  "compatibility_date": "2025-01-01",
  "compatibility_flags": ["nodejs_compat"],
  "account_id": "YOUR_ACCOUNT_ID",

  "vars": {
    "ENVIRONMENT": "production",
    "GITHUB_CLIENT_ID": "optional-pre-configured-id"
  },

  "kv_namespaces": [
    {
      "binding": "OAUTH_KV",
      "id": "YOUR_KV_ID",
      "preview_id": "YOUR_PREVIEW_KV_ID"
    }
  ],

  "durable_objects": {
    "bindings": [
      {
        "name": "MY_MCP",
        "class_name": "MyMCP",
        "script_name": "my-mcp-server"
      }
    ]
  },

  "migrations": [
    { "tag": "v1", "new_classes": ["MyMCP"] }
  ],

  "node_compat": true
}