fetchwerk Web Extraction · Product Compare

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://fetch.halowerk.com/product/compare", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "currency_hint": "GBP",
    "urls": [
      "https://books.toscrape.com/catalogue/a-light-in-the-attic_1000/index.html",
      "https://books.toscrape.com/catalogue/tipping-the-velvet_999/index.html"
    ],
    "want_variants": false
  }),
});
const data = await res.json();

curl -X POST \
  "https://fetch.halowerk.com/product/compare" \
  -H "Content-Type: application/json" \
  -d '{"currency_hint":"GBP","urls":["https://books.toscrape.com/catalogue/a-light-in-the-attic_1000/index.html","https://books.toscrape.com/catalogue/tipping-the-velvet_999/index.html"],"want_variants":false}' \
  -H "X-PAYMENT: <signed x402 payment>"

{
  "compared": 2,
  "comparison": {
    "currencies": [
      "EUR"
    ],
    "identity_matches": [
      {
        "product_indices": [
          0,
          1
        ],
        "type": "gtin",
        "value": "4006381333931"
      }
    ],
    "lowest_listed_price_by_currency": [
      {
        "compared_offers": 2,
        "currency": "EUR",
        "lowest_value": 19.9,
        "product_indices": [
          0
        ]
      }
    ],
    "same_product_proven": true,
    "warnings": []
  },
  "failed": 0,
  "fetched_at": "2026-08-30T10:00:00Z",
  "methodology": {
    "price": "Only stated prices are ranked; currencies are never converted."
  },
  "products": [
    {
      "index": 0,
      "input_url": "https://shop-a.example/item",
      "price": {
        "currency": "EUR",
        "value": 19.9
      },
      "product": {
        "gtin": "4006381333931",
        "name": "Example widget"
      }
    },
    {
      "index": 1,
      "input_url": "https://shop-b.example/item",
      "price": {
        "currency": "EUR",
        "value": 21.5
      },
      "product": {
        "gtin": "4006381333931",
        "name": "Example widget"
      }
    }
  ],
  "requested": 2
}