x402 agent payments
Each operation is POST-only with a fixed USDC price on Base, paid with the x402 exact scheme. An unpaid POST returns 402 payment terms before the body is validated. A request that carries payment-signature is not yet charged: settlement happens only after a successful (2xx) result. HTTP 4xx/5xx are not charged. Coverage bodies with status complete, partial, or failed all return HTTP 200 and are charged at the full listed price. Settled 2xx responses include a payment-response header; 4xx/5xx do not. Compare payTo, asset, and network with the pins on /api/v1/catalog and /.well-known/x402 — not only with what a single 402 says about itself.
Why agents use x402 here
There is no signup and no API key. Each operation lists a fixed USDC price. Agents can discover terms, pay, and call without a human provisioning credentials. That fits autonomous or semi-autonomous workflows that already hold Base USDC.
Pins to verify
Network: eip155:8453. Asset (USDC): 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913· payTo: 0x6428665E83F503904571104311bB78CBb29b975c. Treat mismatches as a hard stop before paying.
Step-by-step
The full walkthrough, idempotency rules, and agent prompt live on How it works. Short answers are on the FAQ.
Where to call
Browse priced operations in the API catalog, machine catalogs at OpenAPI and llms.txt, or wrap the same tools via MCP.
Related use cases
Sanctions screening, MCP for agents, Token security, and all use cases.