Pay for one request
This is the real exchange, not a diagram: a live endpoint on this site answers 402, you sign one EIP-712 authorization against USDG’s own domain, and the server checks the signature and your balance on chain before it answers.
1 · the agent
| signer | — |
| address | — |
| USDG | — |
| ETH | — |
A browser key is generated here and kept in this browser’s storage, nowhere else. It is a throwaway: fund it with cents, not with savings.
what it needs
Dollars, and nothing else
The ETH line above should read zero. An agent paying through Tab never touches gas: it
signs, and whoever wants the request served pays for the transaction. If the USDG line is
zero too, the endpoint will refuse on the balance check — which is
exactly the point. The door is a fact read off the chain, not a flag.
2 · the exchange
| request | — |
| answer | — |
| price | — |
| pay to | — |
| authorization | — |
| nonce | — |
| resource hash | — |
| signature | — |
| settlement | — |
What the server checked
What 0.01 USDG bought
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