MCP Monetization

Monetize any MCP (Model Context Protocol) server with pay-per-tool-call billing. Wrap your existing MCP server with an xpay proxy and start earning from every tool invocation.

Overview

MCP Monetization lets you place a payment layer in front of any MCP server. When an AI assistant (Claude, Cursor, Windsurf, etc.) calls a tool on your server, the payment is processed automatically via the x402 protocol before the tool executes.

• Zero code changes - Your MCP server stays exactly as it is
• Per-tool pricing - Set different prices for different tools
• Instant payouts - Revenue flows directly to your wallet via USDC
• Works everywhere - Compatible with any MCP client

How It Works

1. You register your MCP server URL on xpay and set per-tool pricing
2. xpay gives you a proxy URL: https://{slug}.mcp.xpay.sh/mcp
3. Users connect their AI assistant to the proxy URL instead of your server directly
4. Every tool call is metered and paid for automatically

Quick Start

1. Register Your MCP Server

Go to xpay.sh  and create a new MCP monetization endpoint:

• Server URL: Your MCP server’s SSE or Streamable HTTP endpoint
• Receiving wallet: Your USDC wallet address on Base
• Pricing: Set a default price per tool call, or configure per-tool pricing

2. Configure Per-Tool Pricing

Set different prices for each tool your server exposes:

You can also set a flat rate that applies to all tools.

3. Share Your Proxy URL

Give users your proxy URL to connect in their AI assistant:

https://my-service.mcp.xpay.sh/mcp

4. Connect in Claude Desktop

Users add your monetized MCP server to their claude_desktop_config.json:

{
  "mcpServers": {
    "my-service": {
      "url": "https://my-service.mcp.xpay.sh/mcp",
      "headers": {
        "Authorization": "Bearer USER_API_KEY"
      }
    }
  }
}

5. Connect in Cursor / Windsurf

In Cursor or Windsurf settings, add the MCP server URL:

https://my-service.mcp.xpay.sh/mcp

The AI assistant will automatically handle x402 payments when calling tools.

Pricing Configuration

Flat Rate

Charge the same price for every tool call:

{
  "pricing": {
    "model": "flat",
    "price": 0.05,
    "currency": "USDC"
  }
}

Per-Tool Pricing

Set individual prices for each tool:

{
  "pricing": {
    "model": "per_tool",
    "currency": "USDC",
    "tools": {
      "search": 0.01,
      "analyze": 0.05,
      "generate": 0.10
    },
    "default": 0.02
  }
}

The default price applies to any tool not explicitly listed.

API Key Management

Buyers authenticate with an API key to track their usage and manage spending:

• Get an API key from hub.xpay.sh 
• Include it in the Authorization header when connecting to the MCP proxy
• Track usage and spending in the xpay dashboard
• Set spending limits to control costs

Billing Receipts

After each tool call, the proxy includes billing metadata in the response:

{
  "result": { "...tool output..." },
  "_billing": {
    "tool": "search_web",
    "cost": "0.01",
    "currency": "USDC",
    "txHash": "0xabc...",
    "network": "base",
    "timestamp": "2026-02-22T10:30:00Z"
  }
}

Supported MCP Transports

• Streamable HTTP (recommended) - Modern HTTP-based transport
• SSE (Server-Sent Events) - Legacy streaming transport

Use Cases

• Data providers - Monetize search, enrichment, and lookup tools
• AI model wrappers - Charge per inference via MCP tools
• SaaS integrations - Expose your product’s API as paid MCP tools
• Research services - Charge for web scraping, analysis, and report generation

Ready to monetize your MCP server? Get started on xpay.sh  or explore the x402 Protocol to understand the payment layer.