Open Source · MIT Licensed

Monetize any MCP server
with one command.

Add API key auth, per-tool pricing, rate limiting, and usage metering to any Model Context Protocol server. Zero config. No code changes.

terminal
$ |
npx paygate-mcp wrap --server "your-mcp-server"
Agent
AI agent calls tools
PayGate
Auth + billing + limits
Server
Your MCP server

Everything you need to
sell tool access.

API Key Auth

Cryptographic key generation with pg_ prefix. Keys masked in list endpoints. Admin key never exposed.

Credit Billing

Each tool call costs credits. Set global pricing or per-tool overrides. Integer-only to prevent float exploits.

Rate Limiting

Per-key sliding window rate limits. Concurrent-safe. Set globally or per-tool. Default 60 calls/min.

Usage Metering

Track every call: who, what tool, when, credits charged. Full dashboard via /status endpoint.

Shadow Mode

Log all tool calls without enforcing payment. Perfect for testing and understanding usage patterns before going live.

Zero Config

Works with any MCP server using stdio transport. No code changes needed. Wrap and go in under 60 seconds.

Built for developers who
want to get paid.

🔧

MCP Server Authors

You built a useful MCP server — a code analyzer, data pipeline, or API connector. Now you want to charge AI agents per tool call instead of giving it away for free. Wrap it with PayGate in one command.

🏢

API Providers

You have an existing API and want to expose it to AI agents via MCP. PayGate handles auth, billing, and rate limiting so you can focus on your core service, not building payment infrastructure.

🧪

Internal Teams

Your company runs internal MCP servers for AI assistants. Use PayGate to track which teams use what tools and how much, enforce usage limits, and manage access with API keys.

How it works in practice

1 You wrap your MCP server with PayGate and set a price per tool call
2 You issue API keys to your customers with a credit balance
3 Their AI agents call your tools — credits deducted automatically
4 You charge them for credit top-ups however you like (Stripe, invoice, crypto)

New in v0.1.4: Add --state-file ~/.paygate/state.json to persist keys and credits across restarts. Without it, data lives in memory (great for testing).

Up and running in
60 seconds.

1

Start the gated server

terminal 
npx paygate-mcp wrap \
  --server "npx @modelcontextprotocol/server-filesystem /tmp" \
  --price 2 \
  --rate-limit 30
2

Create an API key

terminal 
curl -X POST http://localhost:3402/keys \
  -H "Content-Type: application/json" \
  -H "X-Admin-Key: YOUR_ADMIN_KEY" \
  -d '{"name": "my-client", "credits": 100}'
3

Call tools with billing

terminal 
curl -X POST http://localhost:3402/mcp \
  -H "Content-Type: application/json" \
  -H "X-API-Key: CLIENT_KEY" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call",
       "params":{"name":"read_file",
       "arguments":{"path":"/tmp/data.txt"}}}'

Clean, minimal
REST API.

Endpoint Method Auth Description
/mcp POST X-API-Key JSON-RPC 2.0 proxy to wrapped server
/keys POST X-Admin-Key Create a new API key with credits
/keys GET X-Admin-Key List all keys (masked)
/topup POST X-Admin-Key Add credits to an existing key
/keys/revoke POST X-Admin-Key Revoke an API key
/status GET X-Admin-Key Full dashboard with usage stats
/ GET None Health check
Free methods: initialize, tools/list, resources/list, prompts/list, and ping pass through without auth or billing.

Start monetizing
your MCP server.

npm install paygate-mcp
npm package · v0.1.4 · MIT License