pay-via-agent-wallet

Run circle services search with a keyword to find a paid endpoint, inspect it with circle services inspect to confirm price and schema, then call circle services pay with your wallet address, chain, and JSON payload. The CLI signs the payment authorization and returns the API response.

x402 is a payment protocol where HTTP endpoints return a 402 challenge specifying price and accepted chains, and clients settle per-call in USDC. It removes the need for API keys, accounts, or prefunded billing when accessing paid services.

Sellers publish accepted chains in their 402 response, and many accept only Polygon or Avalanche rather than BASE. When you see "Seller does not accept --chain X", retry with the chain listed in the CLI's hint, which is authoritative.

Gateway uses the GatewayWalletBatched scheme with sub-500ms settlement after a one-time deposit, while vanilla x402 pays directly on-chain at roughly 2 seconds per call. When a seller lists both, the CLI auto-selects Gateway first.

HTTP 422 means the request payload schema is wrong, not a transient error. Check whether the CLI says payment was not charged (safe to fix --data and retry) or payment was submitted (check the payment log in ~/.circle-cli/payments/ before retrying to avoid double-charging).

Verify the wallet is set up with circle wallet status and confirm a nonzero USDC balance. If login or terms errors appear, use the wallet setup flow first; if balance is zero, fund the wallet via fiat on-ramp, transfer, or Gateway deposit before paying.