Gas

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.liquidagent.ai/v1/gas' \
  -H 'content-type: application/json' \
  --data-raw '{"method":"pm_getPaymasterData","params":[{"callData":"0x","callGasLimit":"0x30d40","maxFeePerGas":"0x5f5e100","maxPriorityFeePerGas":"0xf4240","nonce":"0x0","preVerificationGas":"0x13880","sender":"0xYourSmartAccount","verificationGasLimit":"0x186a0"},"0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108","0x2105",{"x402":"<payment object>"}]}'

# 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://api.liquidagent.ai/v1/gas' \
  -H 'content-type: application/json' \
  --data-raw '{"method":"pm_getPaymasterData","params":[{"callData":"0x","callGasLimit":"0x30d40","maxFeePerGas":"0x5f5e100","maxPriorityFeePerGas":"0xf4240","nonce":"0x0","preVerificationGas":"0x13880","sender":"0xYourSmartAccount","verificationGasLimit":"0x186a0"},"0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108","0x2105",{"x402":"<payment object>"}]}' \
  | 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 $0.03 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.03" });
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 $0.03 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.liquidagent.ai%2Fv1%2Fgas&method=POST
const res = await pay("https://api.liquidagent.ai/v1/gas", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "method": "pm_getPaymasterData",
    "params": [
      {
        "callData": "0x",
        "callGasLimit": "0x30d40",
        "maxFeePerGas": "0x5f5e100",
        "maxPriorityFeePerGas": "0xf4240",
        "nonce": "0x0",
        "preVerificationGas": "0x13880",
        "sender": "0xYourSmartAccount",
        "verificationGasLimit": "0x186a0"
      },
      "0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108",
      "0x2105",
      {
        "x402": "<payment object>"
      }
    ]
  }),
});
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 $0.03 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.03"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://api.liquidagent.ai/v1/gas",
        json={
            "method": "pm_getPaymasterData",
            "params": [
                {
                    "callData": "0x",
                    "callGasLimit": "0x30d40",
                    "maxFeePerGas": "0x5f5e100",
                    "maxPriorityFeePerGas": "0xf4240",
                    "nonce": "0x0",
                    "preVerificationGas": "0x13880",
                    "sender": "0xYourSmartAccount",
                    "verificationGasLimit": "0x186a0",
                },
                "0x4337084D9E255Ff0702461CF8895CE9E3b5Ff108",
                "0x2105",
                {
                    "x402": "<payment object>",
                },
            ],
        },
    )
    print(res.status_code, res.text)