Remote MCP Server On Cloudflare 6lx

🚀 Setting up a Remote MCP Server on Cloudflare

Let's launch a remote MCP server on Cloudflare Workers with OAuth login!

🚀 Quick Start

🔨 Local Development

# Clone the repository
git clone git@github.com:cloudflare/ai.git

# Install dependencies
cd ai
npm install

# Run locally
npx nx dev remote-mcp-server

You should be able to open a browser window at http://localhost:8787/.

🔗 Connecting MCP Inspector to Your Server

To explore the new MCP API, you can use the MCP Inspector.

• Start it using npx @modelcontextprotocol/inspector.
• In the inspector (http://localhost:5173), switch the transport type to SSE, enter http://localhost:8787/sse as the MCP server address in the URL, and then click "Connect".
• You'll be redirected to a (simulated) user/password login screen. Enter any email and password to log in.
• You should be redirected back to the MCP Inspector, and you can now list and call any defined tools!

🔗 Connecting Claude Desktop to Your Local MCP Server

The MCP Inspector is great, but we really want to connect it to Claude! Follow the Anthropic's Quick Start guide, go to "Settings" > "Developer" > "Edit Configuration" in Claude Desktop to find your configuration file. Open the file in a text editor and replace it with the following configuration:

{
  "mcpServers": {
    "math": {
      "command": "npx",
      "args": [
        "mcp-remote",
        "http://localhost:8787/sse"
      ]
    }
  }
}

This will run a local proxy that allows Claude to communicate with your MCP server over HTTP. When you open Claude, a browser window will open, allowing you to log in. You should see available tools in the bottom right corner. As prompted, Claude should call the tools after receiving the correct prompt.

🚀 Deployment to Cloudflare

1. npx wrangler kv namespace create OAUTH_KV
2. Follow the instructions to add the kv namespace ID to wrangler.jsonc.
3. npm run deploy

🔗 Calling Your Newly Deployed Remote MCP Server from a Remote MCP Client

Just as you did in "Local Development" above, run the MCP Inspector: npx @modelcontextprotocol/inspector@latest Then, in the inspector, enter your Worker's workers.dev URL (e.g., worker-name.account-name.workers.dev/sse) as the MCP server address and click "Connect". You are now connected to your MCP server through a remote MCP client.

🔗 Connecting Claude Desktop to Your Remote MCP Server

Update the Claude configuration file to point to your workers.dev URL (e.g., https://worker-name.account-name.workers.dev/sse) and restart Claude.

{
  "mcpServers": {
    "math": {
      "command": "npx",
      "args": [
        "mcp-remote",
        "https://worker-name.account-name.workers.dev/sse"
      ]
    }
  }
}

🐞 Debugging

If any issues arise, restarting Claude or directly connecting to your MCP server using the following command may be helpful:

npx mcp-remote http://localhost:8787/sse

In rare cases, clearing the files in ~/.mcp-auth may be beneficial.