Domain Registration API for AI Agents: Pay with USDC on Base | StableDomains.net

Search and quote need no auth: GET /api/v1/search?q=myagent and GET /api/v1/quote?domain=myagent.com. Create an order with POST /api/v1/orders; the 402 response lists accepts[], e.g. scheme exact on network base with USDC.

Pay in-band by retrying with an X-PAYMENT (or PAYMENT-SIGNATURE) header carrying the signed payload. Other chains and USDT are offered as a 'transfer' scheme: send the exact amount and retry with X-PAYMENT-TX. If a signature is rejected you get HTTP 402 again with the reason and fresh requirements. Full spec: /api/openapi.