NFT collection metadata

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. Send POST /api/nft-collection with the required field contract and pay $0.002 per call over x402 or MPP (there is no free tier). It returns a JSON object with contract, network, name, symbol, tokenType and 13 more.

Use to label a contract address with its collection identity before pulling tokens or sales.

Category: Crypto & onchain data · Tags: nft collection erc721 erc1155 metadata opensea

TRY IN PLAYGROUND →

Parameters

Example request

curl -i -X POST https://agent402.tools/api/nft-collection \
  -H "Content-Type: application/json" \
  -d '{"contract":"0xbc4ca0eda7647a8ab7c2061c2e118a18a936f13d","network":"ethereum"}'

Without payment this returns HTTP 402 Payment Required with the exact price for nft-collection; any x402 v2 or MPP client pays it and retries.

Example response

{
  "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"
}

From an MCP client

catalog.call {
  "slug": "nft-collection",
  "params": {
    "contract": "0xbc4ca0eda7647a8ab7c2061c2e118a18a936f13d",
    "network": "ethereum"
  }
}

The hosted connector at https://agent402.tools/mcp needs a payment for nft-collection; the stdio package pays it from a wallet or from AGENT402_CREDITS_KEY. Local install: npx -y agent402-mcp.

Errors and behavior

• contract is required. An input the tool rejects returns an HTTP 4xx whose body carries error, tool, expected, required and example, so the caller can correct it.
• A paid call that ends in any status of 400 or above is not charged over x402, MPP or a prepaid credits key: settlement is cancelled when the tool fails. The exception is a Tempo push credential, a transfer the buyer sent before the call: it settles before the tool runs, so if the tool then fails the payment is recorded as a refund owed to the paying wallet.
• Wallet-only: this tool reaches the network or stored state, so it has no proof-of-work tier. A prepaid card-credits key issued earlier (Authorization: Bearer a402_...) also pays it.
• A GET or HEAD to /api/nft-collection returns the same 402 quote, so the price can be read without a body.
• An Idempotency-Key header makes a retried paid call replay the first 200 instead of charging again (an answer larger than 1 MB is not replayed).

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();
client.setSpendControls?.(false); // keep your own spending ceiling in code
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"
  }),
});

Related tools