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Deploy your FastMCP server to Cloudflare Workers for ultra-low latency worldwide. The edge runtime allows your MCP server to run close to your users with automatic global distribution.

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EdgeFastMCP vs FastMCP

Cloudflare Workers requires the edge-compatible EdgeFastMCP class:
FeatureFastMCPEdgeFastMCP
RuntimeNode.jsEdge (V8 isolates)
Start methodserver.start({ port })export default server
Transportstdio, httpStream, SSEHTTP Streamable only
SessionsStateful or statelessStateless only
File systemYesNo
OAuth/AuthenticationBuilt-in authenticate optionUse Hono middleware (built-in planned)
Custom routesserver.getApp()server.getApp()
EdgeFastMCP is optimized for stateless edge environments with no filesystem access. Use fetch APIs for external data.

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Step-by-Step Deployment

1

Install Dependencies

Install FastMCP and Zod in your Cloudflare Workers project:
npm install fastmcp zod
2

Create Your MCP Server

Create src/index.ts with the EdgeFastMCP import:
src/index.ts
import { EdgeFastMCP } from "fastmcp/edge";
import { z } from "zod";

const server = new EdgeFastMCP({
  name: "My Edge Server",
  version: "1.0.0",
  description: "MCP server running on Cloudflare Workers",
});

// Add tools, resources, prompts as usual
server.addTool({
  name: "greet",
  description: "Greet someone",
  parameters: z.object({
    name: z.string(),
  }),
  execute: async ({ name }) => {
    return `Hello, ${name}! Served from the edge.`;
  },
});

// Export the server as default (required for Cloudflare Workers)
export default server;
The export default server statement is required for Cloudflare Workers to recognize your handler.
3

Configure wrangler.toml

Create a wrangler.toml configuration file:
wrangler.toml
name = "my-mcp-server"
main = "src/index.ts"
compatibility_date = "2024-01-01"

name = "my-mcp-server"
main = "src/index.ts"
compatibility_date = "2024-01-01"
4

Deploy to Cloudflare

Deploy your MCP server with a single command:
npx wrangler deploy
Your server will be available at:
  • MCP endpoint: https://my-mcp-server.workers.dev/mcp
  • Health check: https://my-mcp-server.workers.dev/health

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Complete Example

Here’s a full example based on src/examples/edge-cloudflare-worker.ts:
src/index.ts
import { EdgeFastMCP } from "fastmcp/edge";
import { z } from "zod";

const server = new EdgeFastMCP({
  description: "An MCP server running on Cloudflare Workers",
  name: "CloudflareWorkerMCP",
  version: "1.0.0",
});

// Simple tool
server.addTool({
  name: "greet",
  description: "Greet someone by name",
  parameters: z.object({
    name: z.string().describe("The name to greet"),
  }),
  execute: async ({ name }) => {
    return `Hello, ${name}! This response is from a Cloudflare Worker.`;
  },
});

// Tool with structured content
server.addTool({
  name: "get_weather",
  description: "Get weather information for a location",
  parameters: z.object({
    location: z.string().describe("The city or location"),
  }),
  execute: async ({ location }) => {
    // Call external API using fetch
    return {
      content: [
        {
          type: "text",
          text: `Weather for ${location}:\n- Temperature: 72°F\n- Conditions: Sunny\n- Humidity: 45%`,
        },
      ],
    };
  },
});

// Static resource
server.addResource({
  uri: "info://server",
  name: "Server Info",
  description: "Information about this MCP server",
  mimeType: "text/plain",
  load: async () => {
    return "This is a FastMCP server running on Cloudflare Workers edge runtime.";
  },
});

// Prompt template
server.addPrompt({
  name: "analyze_code",
  description: "Generate a prompt to analyze code",
  arguments: [
    { name: "language", description: "Programming language", required: true },
    { name: "focus", description: "What to focus on (optional)", required: false },
  ],
  load: async (args) => {
    const focus = args.focus ? ` focusing on ${args.focus}` : "";
    return {
      messages: [
        {
          role: "user",
          content: {
            type: "text",
            text: `Please analyze the following ${args.language} code${focus}:`,
          },
        },
      ],
    };
  },
});

export default server;

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Adding Custom Routes

Access the underlying Hono app to add custom HTTP endpoints: 
const app = server.getApp();

// Add a landing page
app.get("/", (c) => c.html("<h1>Welcome to my MCP server</h1>"));

// Add REST API endpoints
app.get("/api/status", (c) => c.json({ status: "ok", edge: true }));

// Handle POST requests
app.post("/api/data", async (c) => {
  const body = await c.req.json();
  return c.json({ received: body });
});

export default server;

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Environment Variables and Secrets

1

Add Environment Variables

Define variables in wrangler.toml:
[vars]
API_ENDPOINT = "https://api.example.com"
CACHE_TTL = "3600"
2

Add Secrets

Use wrangler CLI for sensitive data:
npx wrangler secret put API_KEY
npx wrangler secret put DATABASE_URL
3

Access in Code

TypeScript doesn’t have direct access to env in EdgeFastMCP. Use Hono middleware:
const app = server.getApp();

app.use("*", async (c, next) => {
  // Access environment variables
  const apiKey = c.env.API_KEY;
  await next();
});
Never commit secrets to wrangler.toml. Always use wrangler secret put for sensitive values.

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Edge Runtime Limitations

When running on Cloudflare Workers, be aware of these constraints:
  • No filesystem access: Use KV, R2, or fetch APIs instead
  • Stateless by default: Each request is handled independently
  • V8 isolates: Limited to JavaScript/TypeScript runtime
  • CPU time limits: Maximum 50ms CPU time on free tier, 30s on paid
  • Memory limits: 128MB per request
  • No long-running connections: Use Durable Objects for websockets
For session state, consider using Cloudflare KV or Durable Objects.

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Testing Locally

Test your worker locally before deploying: 
# Start local development server
npx wrangler dev

# Test the MCP endpoint
curl -X POST http://localhost:8787/mcp \
  -H "Content-Type: application/json" \
  -H "Accept: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "id": 1,
    "method": "tools/list"
  }'

# Test health check
curl http://localhost:8787/health

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Monitoring and Logs

View logs and analytics in the Cloudflare dashboard: 
# Stream logs in real-time
npx wrangler tail

# View metrics
npx wrangler metrics

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Next Steps

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