Build a paid MCP server on Cloudflare

{
  "name": "atxp-mcp-cloudflare-server",
  "version": "0.0.0",
  "private": true,
  "scripts": {
    "deploy": "wrangler deploy",
    "dev": "wrangler dev",
    "start": "wrangler dev",
    "test": "vitest",
    "cf-typegen": "wrangler types"
  },
  "dependencies": {
    "@modelcontextprotocol/sdk": "^1.0.0",
    "@atxp/cloudflare": "^0.4.0", 
    "bignumber.js": "^9.1.2", 
    "zod": "^3.23.8"
  },
  "devDependencies": {
    "@cloudflare/workers-types": "^4.20241112.0",
    "typescript": "^5.5.2",
    "vitest": "2.0.5",
    "wrangler": "^3.86.1"
  }
}

import { McpAgent } from "agents/mcp";
import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { z } from "zod";
import { BigNumber } from "bignumber.js";

// Import ATXP code
import {
	requirePayment,
	atxpCloudflare,
	type ATXPMCPAgentProps,
	type ATXPCloudflareOptions,
} from "@atxp/cloudflare";
import { ATXPPaymentDestination } from "@atxp/server";


const createOptions = (env: Env) => {
	const paymentDestination = new ATXPPaymentDestination(
		env.ATXP_CONNECTION_STRING,
	); 

	paymentDestination.destination =
		paymentDestination.destination.bind(paymentDestination);
	return {
		mcpAgent: MyMCP,
		payeeName: "ATXP MCP Server Demo",
		allowHttp: env.ALLOW_INSECURE_HTTP_REQUESTS_DEV_ONLY_PLEASE === "true",
		// Don't create the payment destination here - create it when needed
		paymentDestination,
	} as ATXPCloudflareOptions;
};

// Define our MCP agent with ATXP payment integration
export class MyMCP extends McpAgent<Env, unknown, ATXPMCPAgentProps> {
	server = new McpServer({
		name: "ATXP-Protected Hello World MCP Server",
		version: "1.0.0",
	});

	async init() {
		// This method will be called when the agent is initialized
		// We'll define our tools here
	}
}

// Use the ATXP Cloudflare Worker wrapper as the default export
export default {
	async fetch(request: Request, env: any, ctx: ExecutionContext): Promise<Response> {
		// Create the handler with environment-based configuration
		const cloudflareOptions = createOptions(env);
		const handler = atxpCloudflare(cloudflareOptions);

		return handler.fetch(request, env, ctx);
	}
};

// Define our MCP agent with ATXP payment integration
export class MyMCP extends McpAgent<Env, unknown, ATXPMCPAgentProps> {
	server = new McpServer({
		name: "ATXP-Protected Hello World MCP Server",
		version: "1.0.0",
	});

	async init() {
		// Payment-protected hello_world tool
		this.server.tool(
			"hello_world",
			{ name: z.string().optional() },
			async ({ name }) => {
				if (!this.props) {
					throw new Error("ATXP props are not initialized");
				}

				const options = createOptions(this.env);
				await requirePayment(
					{
						price: new BigNumber(0.01),
					},
					options,
					this.props,
				);

				const greeting = name ? `Hello, ${name}!` : "Hello, World!";
				const userInfo = this.props.tokenCheck?.data?.sub || "anonymous user";
				const message = `${greeting} Thanks for your 0.01 USDC payment, ${userInfo}! 💰`;

				return {
					content: [{ type: "text", text: message }],
				};
			},
		);
	}
}