Agent Quickstart

Set me up to use Otto AI's pay-per-call x402 API. Do everything yourself and only
stop when you need me to send money:

1. Fetch and read https://x402.ottoai.services/AGENTS.md and
   https://x402.ottoai.services/otto.md. In two sentences, tell me what I'm
   unlocking — roughly how many pay-per-call services, the price range, and that
   there's no signup or API key.
2. Follow the "Self-serve bring-up" recipe in AGENTS.md: create a FRESH throwaway
   wallet (never my main wallet), then show me its address and tell me to send
   about $5 of USDC on the Base network to it.
3. Wait for the funding to arrive, then make the first paid call and show me the
   result plus the on-chain settlement tx hash I can check on Basescan.

Never use or ask for my main wallet's private key. The only thing I will do by
hand is send the USDC.

// otto.mjs — first paid call to Otto AI over x402
import axios from "axios";
import { wrapAxiosWithPayment, x402Client, decodePaymentResponseHeader } from "@x402/axios";
import { ExactEvmScheme } from "@x402/evm/exact/client";
import { toClientEvmSigner } from "@x402/evm";
import { privateKeyToAccount } from "viem/accounts";
import { createPublicClient, http } from "viem";
import { base } from "viem/chains";

// Your wallet. The key stays on your machine — it signs a USDC transfer
// authorization locally; it is never sent to Otto.
const account = privateKeyToAccount(process.env.X402_PRIVATE_KEY);
const publicClient = createPublicClient({ chain: base, transport: http() });

const client = new x402Client();
client.register("eip155:8453", new ExactEvmScheme(toClientEvmSigner(account, publicClient)));

const otto = wrapAxiosWithPayment(
  axios.create({ baseURL: "https://x402.ottoai.services", timeout: 60000 }),
  client,
);

// $0.001 USDC — the client sees the 402, signs the payment, retries, returns data.
const res = await otto.get("/crypto-news");
console.log(res.data);

const receipt = decodePaymentResponseHeader(
  res.headers["payment-response"] ?? res.headers["x-payment-response"],
);
console.log("\nSettled on-chain:", receipt?.transaction);