Remote MCP Server On Cloudflare 23e

🚀 Run a Remote MCP Server on Cloudflare

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

🚀 Quick Start

📦 Installation

# 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/.

💻 Usage Examples

Connecting MCP Inspector to Your Server

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

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

Connecting Claude Desktop to the Local MCP Server

While the MCP inspector is useful, we'd prefer to connect it to Claude! Follow Anthropic's Quick Start Guide, go to "Settings" > "Developer" > "Edit Configuration" in Claude Desktop, and find your configuration file.

Open the file in a text editor and replace its contents 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 via 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. As prompted, Claude may request to call tools.

🚀 Deployment to Cloudflare

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

Connecting Remote MCP Client to Your Deployed Server

Just as you did in the "Local Development" section 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 via the 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 then restart Claude.

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

🔧 Debugging

If you encounter issues, restarting Claude or directly connecting to your MCP server with the following command may help.

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

In rare cases, clearing the files in the ~/.mcp-auth directory may help resolve the issue.

rm -rf ~/.mcp-auth