Cloudflare MCP Server — Code Mode

Serverless starter for building a remote Model Context Protocol (MCP) server on Cloudflare Workers.

The project is designed for code mode: clients can discover capabilities and compose tool calls with structured responses. Arbitrary code execution is not enabled in the starter; it should only be added after defining a sandbox, authentication, limits, and auditing.

Goals

• Run on the edge via Cloudflare Workers.

• Expose an MCP endpoint at /mcp.

• Keep tools small, typed, and composable.

• Prepare OAuth authentication and Cloudflare bindings.

• Evolve to secure code execution in an isolated sandbox.

Related MCP server: remote-mcp-server-authless

Local development

Prerequisites: Node.js 18+ and a Cloudflare account with Workers enabled.

npm install
npm run dev

The local server is available at http://localhost:8788/mcp.

To validate with the MCP Inspector:

npx @modelcontextprotocol/inspector@latest

Deploy

npx wrangler login
npm run deploy

After deploying, the endpoint will be:

https://<worker>.<account>.workers.dev/mcp

Structure

• src/index.ts: Worker HTTP routing.

• src/mcp.ts: MCP server and tools.

• wrangler.jsonc: Worker configuration.

• PLAN.md: implementation plan and acceptance criteria.

Security

Do not add eval, new Function, or a code interpreter directly to the Worker. For code mode with real execution, use an appropriate sandbox, strong authentication, API allowlists, CPU/memory/time limits, per-user isolation, and logs without secrets.

Next steps

See PLAN.md.