HTTP has had a status code sitting unused for 30 years. 402: Payment Required. It was reserved for a future where machines could pay for things directly. That future is here. Stripe and Coinbase are both building around x402 — a protocol that revives 402 to enable AI agents to pay for API calls in USDC, automatically, without a human in the loop. An AI agent requests a resource. The server responds with 402. The agent pays in USDC. Access is granted. No checkout page. No credit card. No human...

HTTP has had a status code sitting unused for 30 years. 402: Payment Required. It was reserved for a future where machines could pay for things directly. That future is here. Stripe and Coinbase are both building around x402 — a protocol that revives 402 to enable AI agents to pay for API calls in USDC, automatically, without a human in the loop. An AI agent requests a resource. The server responds with 402. The agent pays in USDC. Access is granted. No checkout page. No credit card. No human...