what-am-i-signing

Decode an EVM signature request (EIP-712 typed data, Permit/Permit2, or ERC-20 approve calldata) into a structured intent: what token, which spender, how much, until when, plus risk_flags and an action_hint. Deterministic, no LLM. Answers an agent's question 'what am I about to sign?'

Call it in 30 seconds

// npm i x402-fetch viem
import { wrapFetchWithPayment } from "x402-fetch";
import { createWalletClient, http } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { base } from "viem/chains";

const account = privateKeyToAccount(process.env.PRIVATE_KEY); // funds USDC on Base
const wallet = createWalletClient({ account, chain: base, transport: http() });
const fetchWithPay = wrapFetchWithPayment(fetch, wallet);

// Pays the $0.005 USDC automatically on the 402, then returns the real response:
const res = await fetchWithPay("https://x402.dailyelo.com/v1/sign-decode", { method: "POST" });
console.log(await res.json());

# pip install x402 eth-account httpx
import os, asyncio
from eth_account import Account
from x402.clients.httpx import x402HttpxClient

account = Account.from_key(os.environ["PRIVATE_KEY"])  # funds USDC on Base

async def main():
    async with x402HttpxClient(account=account) as client:
        # x402 handles the 402 -> pay ($0.005 USDC) -> retry automatically
        r = await client.get("https://x402.dailyelo.com/v1/sign-decode")
        print((await r.aread()).decode())

asyncio.run(main())

# 1) An unpaid request returns HTTP 402 with the exact payment terms:
curl -i -X POST "https://x402.dailyelo.com/v1/sign-decode" \
  -H 'content-type: application/json' \
  -d '{"domain": {"chainId": 8453, "name": "Permit2", "verifyingContract": "0x000000000022D473030F116dDEE9F6B43aC78BA3"}, "message": {"details": {"amount": "1461501637330902918203684832716283019655932542975", "expiration": "1781176678", "nonce": "0", "token": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"}, "sigDeadline": "1749722278", "spender": "0x66a9893cC07D91D95644AEDD05D03f95e1dBA8Af"}, "primaryType": "PermitSingle"}'

# 2) Paying + retrying requires an x402 client that can sign the USDC
#    authorization (curl alone cannot). See the JS / Python tabs below.

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