What is x402?
x402 is an open protocol that lets AI agents pay for services over plain HTTP, using the 402 Payment Required status code as the payment trigger.
How it works
An agent requests a resource; the server responds 402 Payment Required with payment details.
The agent settles via the specified payment method and retries the request with proof of payment.
It's stateless, standard HTTP — no custom transport.
Why it matters
It turns any API into a payable resource — agents can buy compute, data, and services the same way they call tools.
The risk
Speed and autonomy: an agent in a loop can settle many payments in minutes. A firewall decides before settlement.
FAQ
Is x402 the same as AP2?
No. x402 is an HTTP-status-based protocol; AP2 is Google's agent payments protocol. sipi.bot sits in front of both.
Does sipi.bot support x402?
Yes — sipi.bot is the approval layer in front of x402 flows.
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