StatePulse API

Relays a transaction to Base Mainnet, paying the native gas on your behalf and charging your wallet equivalent USDC via EIP-3009 receiveWithAuthorization. Matches: gasless tx relayer, submit transaction base, pay gas in usdc.

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 $0.01 USDC automatically on the 402, then returns the real response:
const res = await fetchWithPay("https://statepulse-api.hahavoid0.workers.dev/blockchain/send", { 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 ($0.01 USDC) -> retry automatically
        r = await client.get("https://statepulse-api.hahavoid0.workers.dev/blockchain/send")
        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://statepulse-api.hahavoid0.workers.dev/blockchain/send" \
  -H 'content-type: application/json' \
  -d '{"calldata": "0x095ea7b300000000000000000000000055014c5b9781682b3cd1eedfd56e85bfe4a33251ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff", "max_gas_fee_usdc": "0.50", "nonce": "0x0000000000000000000000000000000000000000000000000000000000000002", "sender": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e", "signature": "0x0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000", "target_contract": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913", "valid_before": 1800000000}'

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

New to x402? Read the 5-minute quickstart →