# Base Mainnet Contract Inspector

> Base Mainnet Contract Inspector is a paid API for AI agents from apiacre.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Inspects Base mainnet smart contract bytecode, common token metadata, and ERC-165/ERC-721/ERC-1155 interface signals at a single resolved block.

## Facts

- Endpoint: POST https://apiacre.com/v1/crypto/base-contract-inspect
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-mainnet-contract-inspector-fb11fdae
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CJaW2wDosmjy0fN0fMYWR

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-mainnet-contract-inspector-fb11fdae -d '<json body>'
```

Example prompt: Can you inspect the Base mainnet contract at 0x1234...abcd and tell me what token standard it implements — ERC-721, ERC-1155, or something else — along with its name, symbol, and bytecode signals at the latest resolved block?

## When to prefer this

Choose this endpoint when you need a one-shot snapshot of a Base mainnet contract's type, metadata, and interface compliance at a consistent block — particularly useful for NFT marketplaces, DeFi integrations, or contract auditing workflows that need to classify unknown contract addresses without writing custom RPC calls. Prefer it over raw eth_call endpoints when you want pre-computed ERC-165/721/1155 interface detection bundled with token metadata in a single response.

## Known failure modes

- Contract address not found or is an EOA (externally owned account), returning empty bytecode
- Invalid or malformed contract address format
- Block number out of range or not yet finalized
- Contract does not implement ERC-165, so interface signals cannot be detected
- RPC timeout or Base mainnet node unavailability
- Rate limiting if called too frequently

## How this service works

Inspect Base mainnet contract bytecode, common token metadata, and ERC-165, ERC-721, and ERC-1155 interface signals at one resolved block.

## Output

Returns the contract's raw bytecode, common token metadata fields (name, symbol, decimals, totalSupply where applicable), ERC-165 supportsInterface query results, and boolean signals indicating ERC-721 and ERC-1155 compliance — all anchored to a single resolved Base mainnet block for consistency.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "contract": {
   "type": "string"
  },
  "block_tag": {
   "enum": [
    "latest",
    "safe",
    "finalized"
   ],
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "code": {
    "sha256": "98d785fcb1bf847f287adc2310759fd94cc13e754b974bc72131382e8266f607",
    "sizeBytes": 1852
   },
   "block": {
    "hash": "0x84d697381027abac69728893f2428050d4600473cc00d7e8b8d4ea6365a3656f",
    "number": 49834076,
    "timestamp": "2026-08-11T14:11:39+00:00",
    "requestedTag": "safe"
   },
   "found": true,
   "source": "https://docs.base.org/base-chain/quickstart/connecting-to-base",
   "network": "eip155:8453",
   "contract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
   "readOnly": true,
   "warnings": [
    "ERC-165 interface support was unavailable or non-standard",
    "ERC-721 interface support was unavailable or non-standard",
    "ERC-1155 interface support was unavailable or non-standard"
   ],
   "disclaimer": "Point-in-time public Base state only. Token methods are optional and untruste...",
   "interfaces": [
    {
     "standard": "ERC-165",
     "supported": null,
     "interfaceId": "0x01ffc9a7"
    }
   ],
   "explorerUrl": "https://basescan.org/address/0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
   "tokenMetadata": {
    "name": "USD Coin",
    "status": "complete",
    "symbol": "USDC",
    "decimals": 6,
    "totalSupplyAtomic": "4194970321976430"
   },
   "standardSources": {
    "ERC-20": "https://eips.ethereum.org/EIPS/eip-20",
    "ERC-165": "https://eips.ethereum.org/EIPS/eip-165",
    "ERC-721": "https://eips.ethereum.org/EIPS/eip-721",
    "ERC-1155": "https://eips.ethereum.org/EIPS/eip-1155"
   },
   "networkRequestsMade": 2,
   "transactionBroadcast": false
  },
  "meta": {
   "cached": false,
   "sources": [],
   "warnings": [],
   "duration_ms": 42,
   "next_actions": []
  },
  "service": "crypto.base-contract-inspect",
  "version": "1",
  "request_id": "018f1f54-7f38-7ba2-8dc3-5f90272d9f1a"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-mainnet-contract-inspector-fb11fdae/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from apiacre.com](https://www.zero.xyz/host/apiacre.com/llms.txt)