MCP Billing Gateway Server

Reverse proxy that adds Stripe billing and x402 crypto payments to any MCP server

Documentation

MCP Billing Gateway

Add Stripe subscriptions, per-call credits, and x402 crypto payments to any MCP server — without writing billing code.

MCP Billing Gateway is a hosted billing proxy that sits between AI agents and your MCP server. It handles payment verification, usage tracking, and tier enforcement automatically. You register your server, set a pricing plan, and point callers to the proxied URL. No billing code required.

Live service: https://mcp-billing-gateway-production.up.railway.app

Installation

pip install mcp-billing-gateway

Or with uvx:

uvx mcp-billing-gateway

Configuration for Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "mcp-billing-gateway": {
      "command": "uvx",
      "args": ["mcp-billing-gateway"]
    }
  }
}

Configuration for Cursor

Add to .cursor/mcp.json in your project:

{
  "mcpServers": {
    "mcp-billing-gateway": {
      "command": "uvx",
      "args": ["mcp-billing-gateway"]
    }
  }
}

Restart your editor after adding the configuration to activate the MCP server.

Tools

Tool	Description
`get_billing_info`	Returns service capabilities, supported payment methods, features, and integration docs

The local MCP server provides service discovery. The full billing functionality runs on the hosted gateway — register as an operator and proxy your MCP servers through it.

How it works

AI Agent → MCP Billing Gateway → Your MCP Server
            (billing enforced here)

Register as an operator and get an API key
Register your MCP server URL + pricing plan
Point callers to your proxy slug: https://mcp-billing-gateway-production.up.railway.app/proxy/{your-slug}/mcp
Callers pay via Stripe API key or x402 USDC — billing is handled transparently

Features

Per-call billing — charge callers per tool call (fiat or crypto)
Subscriptions — monthly/annual Stripe plans with call limits
Tiered pricing — free tier + paid tiers based on usage
x402 micropayments — accept USDC on Base from AI agents with no API keys
Operator dashboard — track revenue, usage, and callers in real time
MCP transport — full Streamable HTTP MCP transport at /mcp/ endpoint

Quick Start

1. Register as operator

curl -X POST https://mcp-billing-gateway-production.up.railway.app/api/v1/operator/register \
  -H "Content-Type: application/json" \
  -d '{"email": "[email protected]", "name": "Your Name"}'

Response:

{
  "operator_id": "op_abc123",
  "api_key": "bg_live_xxxxxxxxxxxx",
  "message": "Operator registered successfully"
}

2. Register your MCP server

curl -X POST https://mcp-billing-gateway-production.up.railway.app/api/v1/servers \
  -H "Authorization: Bearer bg_live_xxxxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "My MCP Server",
    "upstream_url": "https://your-mcp-server.com/mcp",
    "proxy_slug": "my-server"
  }'

3. Create a pricing plan

curl -X POST https://mcp-billing-gateway-production.up.railway.app/api/v1/servers/{server_id}/plans \
  -H "Authorization: Bearer bg_live_xxxxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Pay as you go",
    "billing_model": "per_call",
    "price_per_call_usd_micro": 10000,
    "free_calls_per_month": 100
  }'

4. Connect callers to your proxied server

{
  "mcpServers": {
    "my-server": {
      "url": "https://mcp-billing-gateway-production.up.railway.app/proxy/my-server/mcp",
      "headers": {
        "Authorization": "Bearer CALLER_API_KEY"
      }
    }
  }
}

Payment Methods

Method	Best for	How
Stripe subscription	Human developers	Monthly or annual plan via Stripe Checkout
Stripe per-call	Human developers	Credits consumed per tool call
x402 micropayments	AI agents	USDC on Base, no API keys needed

Examples

Check gateway capabilities

# Using the MCP client
result = await session.call_tool("get_billing_info")
print(result)
# {
#   "service": "MCP Billing Gateway",
#   "version": "0.1.0",
#   "payment_methods": ["stripe_subscription", "stripe_metered", "x402_crypto"],
#   "features": ["Per-call usage tracking", "Tiered pricing", ...],
#   "live_service": "https://mcp-billing-gateway-production.up.railway.app"
# }

Register and monetize an existing MCP server

# 1. Register
API_KEY=$(curl -s -X POST .../api/v1/operator/register \
  -H "Content-Type: application/json" \
  -d '{"email": "[email protected]", "name": "Dev"}' | jq -r .api_key)

# 2. Add your server
SERVER_ID=$(curl -s -X POST .../api/v1/servers \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name": "my-tool", "upstream_url": "https://my-tool.com/mcp", "proxy_slug": "my-tool"}' \
  | jq -r .server_id)

# 3. Set pricing: $0.01 per call, 100 free calls/month
curl -X POST .../api/v1/servers/$SERVER_ID/plans \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"name": "Starter", "billing_model": "per_call", "price_per_call_usd_micro": 10000, "free_calls_per_month": 100}'

# Callers now connect via: .../proxy/my-tool/mcp

Operator Dashboard

Access your dashboard at:

https://mcp-billing-gateway-production.up.railway.app/dashboard

Track revenue, usage, active callers, and configure your servers in real time.

API Reference

Operator endpoints

Endpoint	Method	Description
`/api/v1/operator/register`	POST	Create operator account
`/api/v1/operator/profile`	GET	View profile and API keys
`/api/v1/operator/stats`	GET	Revenue and usage stats

Server management

Endpoint	Method	Description
`/api/v1/servers`	POST	Register an MCP server
`/api/v1/servers`	GET	List your servers
`/api/v1/servers/{id}/plans`	POST	Create pricing plan

Proxy

Endpoint	Method	Description
`/proxy/{slug}/*`	ANY	Proxied calls with billing enforcement
`/mcp/`	ANY	Streamable HTTP MCP transport

Architecture

┌─────────────┐     ┌──────────────────────┐     ┌──────────────────┐
│  AI Agent /  │────▶│  MCP Billing Gateway │────▶│  Your MCP Server │
│  MCP Client  │◀────│  (hosted on Railway)  │◀────│  (upstream)      │
└─────────────┘     └──────────────────────┘     └──────────────────┘
                         │
                         ├── Payment verification (Stripe / x402)
                         ├── Usage tracking & rate limiting
                         ├── Tier enforcement
                         └── Operator dashboard

The gateway is a transparent proxy. Callers interact with your MCP server normally — the gateway intercepts requests, verifies payment, tracks usage, and forwards to your upstream server.

Self-hosted

The gateway is open for use at the hosted URL above. For self-hosted deployments, clone the server repository and deploy via Docker:

docker build -t mcp-billing-gateway .
docker run -p 3000:3000 mcp-billing-gateway

License

MIT