Responses metered (OpenAI · Metered Responses

import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";

const account = privateKeyToAccount(process.env.PRIVATE_KEY);
const fetchWithPay = wrapFetchWithPayment(fetch, account);

const res = await fetchWithPay("https://agent402.tools/v1/metered/responses", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "input": "Summarize x402 in one sentence.",
    "model": "anthropic/claude-haiku-4.5"
  }),
});
const data = await res.json();

curl -X POST \
  "https://agent402.tools/v1/metered/responses" \
  -H "Content-Type: application/json" \
  -d '{"input":"Summarize x402 in one sentence.","model":"anthropic/claude-haiku-4.5"}' \
  -H "X-PAYMENT: <signed x402 payment>"

{
  "id": "resp_…",
  "model": "openai/gpt-4o-mini",
  "object": "response",
  "output": [
    {
      "content": [
        {
          "annotations": [],
          "text": "x402 is an HTTP-native way for agents to pay per request with USDC.",
          "type": "output_text"
        }
      ],
      "id": "msg_…",
      "role": "assistant",
      "status": "completed",
      "type": "message"
    }
  ],
  "status": "completed",
  "usage": {
    "input_tokens": 14,
    "output_tokens": 18,
    "total_tokens": 32
  }
}