Making x402 programmable: extending the HTTP-payments flow with Smart Accounts & Contracts
x402 is doing something very useful and at the same time simple : resurrecting HTTP 402 Payment Required as a standard way for machines to ask for payment and then retry the same HTTP request with proof of payment. The result is an internet-native payment handshake that works for APIs, AI agents, and micro-services—without accounts, API keys, or subscription checkout flows.

Aitor
Jan 15, 2026