Why does x402 exist? What problem does it solve?

The web's payment layer was built for humans: cards, checkout forms, CAPTCHAs, subscriptions. None of that works for an AI agent that needs to buy one API call, one dataset row, or 24 hours of compute — the transaction is too small for card fees, and the checkout flow assumes fingers and eyeballs. Meanwhile, agents are becoming a huge share of web traffic, and services that used to be funded by human ad views need a way to charge machine visitors instead. x402 is the fix for both sides at once: services get a standard way to say 'this costs $0.01' in the response itself, and agents get a standard way to pay it instantly. That's why the big infrastructure players moved — AWS turned it on across CloudFront in June 2026, and Cloudflare followed within two weeks. When the companies that carry the internet's traffic both wire in the same payment protocol in the same month, it stops being an experiment.