# base-nft-owner

> base-nft-owner is a paid API for AI agents from x402.agentindex.world, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-11).

Looks up the current owner wallet address of a specific ERC721 NFT on Base mainnet by calling ownerOf(tokenId).

## Facts

- Endpoint: GET https://x402.agentindex.world/base/nft-owner?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-nft-owner-1ab59fea
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FHY3Bcx9VSNfnIAj4ViSE

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability base-nft-owner-1ab59fea
```

Example prompt: Who owns token ID 1337 of the NFT contract 0xd4307e0acd12cf46fd6cf93bc264f5d5d1598792 on Base mainnet?

## When to prefer this

Use this endpoint when you need to resolve the current owner of a specific ERC721 NFT on Base mainnet and have both the contract address and token ID. Prefer this over generic blockchain explorers when you need a programmatic, pay-per-call lookup without maintaining RPC infrastructure or API keys.

## Known failure modes

- Token ID does not exist or has not been minted — contract reverts, returns error
- Invalid or non-ERC721 contract address provided
- Contract address is not deployed on Base mainnet
- Token has been burned — ownerOf may revert or return zero address
- Network RPC timeout or Base node unavailability

## How this service works

Who owns this NFT? ERC721 owner lookup on Base mainnet via ownerOf(tokenId).

## Output

Returns the wallet address (Ethereum address string) of the current owner of the specified ERC721 token on Base mainnet, as returned by the contract's ownerOf(tokenId) function.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "token": {
   "type": "string",
   "title": "Token"
  },
  "token_id": {
   "type": "integer",
   "title": "Token Id",
   "minimum": 0
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-nft-owner-1ab59fea/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.agentindex.world](https://www.zero.xyz/host/x402.agentindex.world/llms.txt)