Tx Explain

{
  "calldata": {
    "candidates": [
      {
        "args": [
          "0x111111125421cA6dc452d289314280a0f8842A65",
          "115792089237316195423570985008687907853269984665640564039457584007913129639935"
        ],
        "signature": "approve(address,uint256)"
      }
    ],
    "decoded": {
      "args": [
        "0x111111125421cA6dc452d289314280a0f8842A65",
        "115792089237316195423570985008687907853269984665640564039457584007913129639935"
      ],
      "signature": "approve(address,uint256)"
    },
    "selector": "0x095ea7b3",
    "signaturesFound": 1,
    "source": "built-in"
  },
  "disclaimer": "Informational, not a security guarantee. looks_ok does not mean safe. No simulation, no on-chain state (proxy implementations, spender code, balances) is checked.",
  "flags": [
    {
      "code": "UNLIMITED_APPROVAL",
      "level": "high",
      "msg": "Unlimited token approval: spender can drain this token at any time."
    }
  ],
  "kind": "transaction",
  "risk": "high",
  "summary": [
    "Approve 0x111111125421cA6dc452d289314280a0f8842A65 (1inch v6 Router) to spend UNLIMITED units of token 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
  ],
  "to": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
  "toLabel": "USDC (Base)",
  "valueWei": "0",
  "verdict": "do_not_sign_unless_intended"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://lumenworks-x402-decoder.onrender.com/v1/tx/explain' \
  -H 'content-type: application/json' \
  --data-raw '{"chainId":8453,"transaction":{"data":"0x095ea7b3000000000000000000000000111111125421ca6dc452d289314280a0f8842a65ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff","to":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","value":"0"}}'

# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - -X POST 'https://lumenworks-x402-decoder.onrender.com/v1/tx/explain' \
  -H 'content-type: application/json' \
  --data-raw '{"chainId":8453,"transaction":{"data":"0x095ea7b3000000000000000000000000111111125421ca6dc452d289314280a0f8842a65ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff","to":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","value":"0"}}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

// Pays at most $0.002 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.002" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);

// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.002 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Flumenworks-x402-decoder.onrender.com%2Fv1%2Ftx%2Fexplain&method=POST
const res = await pay("https://lumenworks-x402-decoder.onrender.com/v1/tx/explain", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "chainId": 8453,
    "transaction": {
      "data": "0x095ea7b3000000000000000000000000111111125421ca6dc452d289314280a0f8842a65ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
      "to": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "value": "0"
    }
  }),
});
console.log(res.status, await res.text());

# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client

# Pays at most $0.002 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.002"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://lumenworks-x402-decoder.onrender.com/v1/tx/explain",
        json={
            "chainId": 8453,
            "transaction": {
                "data": "0x095ea7b3000000000000000000000000111111125421ca6dc452d289314280a0f8842a65ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
                "to": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
                "value": "0",
            },
        },
    )
    print(res.status_code, res.text)