Agentic Preconfirmations.
Gasless. Pay per request. No lockup of funds.
ETHGas speaks native HTTP 402. Agents buy a preconfirmation with a single signed request — gasless payment and the preconfirmed transaction lands in the next available block. No session, no top-ups, no held balances.
Watch one request become a paid preconfirmation.
Run the exchange step by step. The user asks for blockspace, ETHGas answers with a 402 challenge, the wallet signs it, and the facilitator moves funds so you don’t have to pay any gas — all before the block is built.
One approval. Every request after is a single signature.
The user approves WETH once to the standard permit2 contract. Then an agent can initiate payment and get preconfirmation on their behalf.
The user grants a one-time token approval to the standard permit2 contract. No further on-chain action is needed from them.
An app or agent hits the x402 endpoint to initiate a preauthorized transaction on the user's behalf.
ETHGas responds with a typed payload — the challenge — that the user must sign to authorize the spend.
After signing, the facilitator moves funds on behalf of the user. No gas is paid by the user.
The transaction is sequenced into the next available block.
Standard 402. No SDK required.
Any HTTP client can drive the flow. Request the resource, read the challenge from the 402 response, sign it, and retry with the payment response header. ETHGas verifies and returns the preconf receipt.
Signature scheme the caller must use — permit2 transfer back by eip712 signature.
The caller returns the signature back to ETHGas server.
ETHGas returns a successful preconfirmation.
Integrate x402 preconfirmations in an afternoon. Standard HTTP, one approval, gasless from there.