Preflight

Call before signing an Ethereum or Base transaction or calldata. Decodes raw transaction bytes or contract calldata against standard interfaces (ERC-20, ERC-721, ERC-1155, WETH, EIP-2612 Permit and Permit2) in memory. Returns the decoded method signature, typed parameters, value in wei and standard specification links. Mechanical byte decoding only: never simulates state or advises whether to sign

Open endpoint ↗

Price per call: $0.10
Chain: Base
Method: POST
Paid calls · 30 days: 1

Call it from code

This API is run by its own provider and paid directly through x402. We list it so you can find it; we don't route or hold the payment.

import { x402Client, wrapFetchWithPayment } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";

const client = new x402Client();
registerExactEvmScheme(client, { signer: agentAccount });

const pay = wrapFetchWithPayment(fetch, client);
const res = await pay("https://preflight402.com/v1/evm/tx-inspect", { method: "POST" });
console.log(await res.json());

https://preflight402.com/v1/evm/tx-inspect