mcp-cloudflare-builder

MCP Cloudflare Builder

Scaffolds and deploys production-ready Model Context Protocol servers on Cloudflare Workers.

Description

Creates remote MCP servers using the McpAgent Durable Object pattern on Cloudflare Workers. Covers tool definition with Zod validation, public vs. OAuth-protected modes, local testing with MCP Inspector, Wrangler deployment, and client connection. Distinct from mcp-builder (which covers general MCP server concepts) and mcp-server-builder (which scaffolds from OpenAPI specs) — this skill is Cloudflare-specific and deployment-complete.

When to Use

• User wants a remote (not stdio) MCP server
• User needs to expose tools to Claude Desktop or other MCP clients over HTTPS
• User wants MCP authentication via OAuth (GitHub, Google, Auth0, etc.)
• User is deploying on Cloudflare Workers specifically

Workflow

Step 1: Scaffold the Project

Public server (no auth):

npm create cloudflare@latest -- my-mcp-server \
  --template=cloudflare/ai/demos/remote-mcp-authless
cd my-mcp-server && npm start

Server runs at http://localhost:8788/mcp.

OAuth-protected server:

npm create cloudflare@latest -- my-mcp-server \
  --template=cloudflare/ai/demos/remote-mcp-github-oauth
cd my-mcp-server

Step 2: Define Tools

Tools are functions MCP clients can call. Define them in McpAgent.init():

import { McpAgent } from "agents/mcp";
import { z } from "zod";

export class MyMCP extends McpAgent {
  server = new Server({ name: "my-mcp", version: "1.0.0" });

  async init() {
    this.server.tool(
      "add",
      { a: z.number(), b: z.number() },
      async ({ a, b }) => ({
        content: [{ type: "text", text: String(a + b) }],
      })
    );

    this.server.tool(
      "get_weather",
      { city: z.string() },
      async ({ city }) => {
        const response = await fetch(`https://api.weather.com/${city}`);
        const data = await response.json();
        return { content: [{ type: "text", text: JSON.stringify(data) }] };
      }
    );
  }
}