How do I integrate x402 into my API?
There are three typical integration patterns. (1) Use the official x402 server SDK in Node, Python, or Go - you wrap a handler and declare a price per route. (2) Put a gateway or reverse proxy in front of an existing API - services like AgentPay and the x402 gateway handle enforcement without code changes. (3) Implement the protocol directly - return 402, include the payment-requirements header, verify the payment-proof header against a facilitator on retry. Option (1) is the fastest for most teams.