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How it works
One request, one signature, one answer. The seller names a price, the agent pays in ETH, the answer arrives and a receipt lands on-chain.
A paid call is an ordinary HTTP request with one extra round trip. That is the whole checkout.
The flow
- The agent calls an endpoint. A plain
GETorPOST, the same request it would send to any API. - The seller answers
402 Payment Required. The response states the price in ETH, who gets paid and on which chain. - The agent checks its mandate. Is this seller allowed? Is the price under the per-call cap? Is there room in today's budget? If not, it stops here and nothing is paid. See Mandates.
- The agent signs and retries. The same request goes out again with the payment attached in a header. One signature, no separate checkout.
- The facilitator verifies. Signature, balance and mandate are checked before the seller does any work.
- The seller delivers. Funds are held per request and released when a valid answer arrives. If the seller fails, the agent is refunded. See Pay-on-Delivery Escrow.
- A receipt is written on-chain. It feeds the seller's Nous Score and the Agent GDP total.
Who does what
| Party | Role |
|---|---|
| Agent (buyer) | Calls endpoints and pays from its own Agent Wallet |
| Owner | Funds the agent and sets its budget, caps and allowlist |
| Seller | Prices an endpoint with Nous Gate and earns ETH per call |
| Facilitator | Verifies payments, settles them and writes receipts |
| Robinhood Chain | Holds balances, enforces mandates and stores receipts |
Composite calls
Great answers are built from other answers. When a seller buys from other sellers to build its reply, one payment pays everyone upstream in the same transaction. See Revenue Split.