HTTP/1.1 402 PAYMENT REQUIRED agent402.base.eth · BASE · SOLANA · POLYGON · ARBITRUM · MONAD · CELO · AVALANCHE · SEI · OPTIMISM · STELLAR · ALGORAND · ROBINHOOD · USDC · USDG
Agent402 / tools / nft-metadata

NFT metadata lookup

$0.001 per call · USDC via x402 · POST /api/nft-metadata

Resolve the metadata for a single NFT: title, description, image URLs (original + cached CDN), attributes/traits, and the standard (ERC-721 vs ERC-1155). Useful when you have a contract+tokenId and need the display data without re-fetching the whole collection.

Input

FieldTypeDescription
contract *string0x-prefixed 40-char NFT contract address.
tokenId *stringToken ID as a string (decimal or hex).
networkstringethereum / base / polygon / arbitrum / optimism (default base).

Example output

{
  "contract": "0xed5af388653567af2f388e6224dc7c4b3241c544",
  "tokenId": "1",
  "network": "ethereum",
  "title": "Azuki #1",
  "collection": "Azuki",
  "standard": "ERC721",
  "description": "Azuki starts with…",
  "image": "https://example.com/azuki1.png",
  "attributes": [
    {
      "trait_type": "Hair",
      "value": "Pink Hairband"
    }
  ]
}

Try it - see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/nft-metadata \
  -H "Content-Type: application/json" \
  -d '{"contract":"0xed5af388653567af2f388e6224dc7c4b3241c544","tokenId":"1","network":"ethereum"}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/nft-metadata", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "contract": "0xed5af388653567af2f388e6224dc7c4b3241c544",
    "tokenId": "1",
    "network": "ethereum"
  }),
});
Wallet-only. This tool reaches the network/browser/storage, so it is paid in USDC via x402 (no proof-of-work tier).

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