Remote MCP Server On Cloudflare 5us

🚀 Set Up a Remote MCP Server on Cloudflare

Let's get a remote MCP server up and running on Cloudflare Workers and integrate OAuth login functionality!

🚀 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/.

Connect the 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, switch the transport type to SSE, enter http://localhost:8787/sse in the URL to connect to the MCP server, and then click "Connect".
• You'll be navigated to a (mock) 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!

Connect Claude Desktop to Your Local MCP Server

The inspector is great, but we really want to connect it to Claude! Follow Anthropic's Quick Start Guide, and in Claude Desktop, go to Settings > Developer > Edit Configuration 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 should open and allow you to log in. You should see a list of available tools in the bottom right corner. Given the right prompt, Claude should request to call a tool.

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

Call 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 URL of the MCP server, and click "Connect".

You've connected to your MCP server via a remote MCP client.

Connect 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 then restart Claude.

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

Debugging

If anything goes wrong, restarting Claude or connecting directly to your MCP server via the following command may help.

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

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

rm -rf ~/.mcp-auth