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-collection

NFT collection metadata

$0.002 per call · USDC via x402 · POST /api/nft-collection

Fetch NFT collection (ERC-721 / ERC-1155) metadata by contract address on Ethereum, Base, Polygon, Arbitrum, or Optimism: name, symbol, token type, total supply, deployer, OpenSea slug + image, floor (ETH), Twitter/Discord, and verification (safelist) status. Use to label a contract address with its collection identity before pulling tokens or sales.

Input

FieldTypeDescription
contract *stringNFT contract address (0x-prefixed 40-hex).
networkstringChain: ethereum, base, polygon, arbitrum, optimism (default ethereum).

Example output

{
  "contract": "0xbc4ca0eda7647a8ab7c2061c2e118a18a936f13d",
  "network": "ethereum",
  "name": "BoredApeYachtClub",
  "symbol": "BAYC",
  "tokenType": "ERC721",
  "totalSupply": "10000",
  "deployedBlockNumber": 12287507,
  "deployerAddress": "0xaba7161a7fb69c88e16ed9f455ce62b791ee4d03",
  "openSeaSlug": "boredapeyachtclub",
  "openSeaImage": "https://...",
  "floorPrice": 13.5,
  "floorPriceSource": "opensea",
  "safelistStatus": "verified",
  "description": "The Bored Ape Yacht Club is a collection of 10,000 unique Bored Ape NFTs.",
  "externalUrl": "https://boredapeyachtclub.com",
  "twitterUsername": "BoredApeYC",
  "discordUrl": "https://discord.gg/3P5K3dzgdB",
  "source": "alchemy-nft-v3"
}

Try it - see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/nft-collection \
  -H "Content-Type: application/json" \
  -d '{"contract":"0xbc4ca0eda7647a8ab7c2061c2e118a18a936f13d","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-collection", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "contract": "0xbc4ca0eda7647a8ab7c2061c2e118a18a936f13d",
    "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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