Remote MCP Server On Cloudflare Glt

🚀 Building a Remote MCP Server on Cloudflare

Let's build a running remote MCP server on Cloudflare Workers and integrate 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 the MCP Inspector to Your Server

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

• Start it using npx @modelcontextprotocol/inspector.
• Switch the transport type to SSE in the inspector and enter http://localhost:8787/sse as the URL of the MCP server, then click "Connect".
• You'll be navigated 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 Anthropic's Quick Start and 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 content:

{
  "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 should open and allow you to log in. You should see available tools in the bottom right corner. With the right prompts, Claude should ask to call the tools.

🚀 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

🔗 Connecting a Remote MCP Client to Your Newly Deployed Remote MCP Server

Just as you did in "Local Development" above, run the MCP Inspector: npx @modelcontextprotocol/inspector@latest

Then enter your Worker's workers.dev URL (e.g., worker-name.account-name.workers.dev/sse) as the URL of the MCP server in the inspector and click "Connect".

You've connected to your MCP server via 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., 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 occur, restarting Claude or directly connecting to your MCP server via the following command may help.

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

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

rm -rf ~/.mcp-auth