x402 Explained: HTTP‑Native Micropayments for AI Agents (With Real Code)

Описание и применение

Реализация микроплатежей для автономных ИИ‑агентов с использованием HTTP‑402 и протокола x402, позволяющая выполнять платежи в цепочке блокчейнов и получать сервисы в ответ.

Задача

Developers building autonomous AI agents need a lightweight, standards‑based way to discover, call, and pay for micro‑services without creating custom billing layers.

Результат

Implemented a self‑contained Node.js example demonstrating the full x402 flow, enabling stateless, atomic micropayments for AI agent services.

Рабочий процесс

• Client sends normal HTTP request to micro‑service
• Server responds 402 with Pay header containing payment pointer and metadata
• Client creates blockchain transaction to pay the specified amount
• Client retries request with X‑Payment header containing transaction proof
• Server validates proof and returns 200 with payload or repeats 402 if invalid

Доказательства

The server responds 402 with a header (Pay) that tells the client how and how much to pay.

Источник

Below is a self‑contained example that shows both sides of the flow.

Источник