1
The agent asks for something
An AI agent sends a normal web request for a resource — an API call, a dataset, a paid article. No account, no login, no card on file.
2
The server answers: 402
HTTP/1.1 402 Payment Required
A real, decades-old status code — reserved since 1997 and almost never used — comes back with a price attached.
3
The agent pays and re-asks
The agent signs a small stablecoin payment, attaches it to the same request, and sends it again — no new account, no checkout page.
4
The resource is served
The whole exchange finishes in seconds. On the live network today, the average payment is well under a dollar.