Glossary ยท AI
x402 Micropayments
HTTP 402-based protocol for pay-per-request API access using cryptocurrency.
Definition
x402 is an HTTP 402 ("Payment Required") based micropayment protocol that lets developers and AI agents pay per API request in cryptocurrency without traditional API keys. Each request is paid for individually at the moment of the call. Spectre AI accepts USDC on Base for x402 payments, making autonomous agent integrations frictionless - the agent discovers an endpoint, pays, and receives data without human-in-the-loop key provisioning.
See this concept live in Spectre AI: /website2/api