# Ethereum Onchain Data – Address Type & Contract Metadata

> Ethereum Onchain Data – Address Type & Contract Metadata is a paid API for AI agents from ca-tax-api-mainnet.lxtap.workers.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-23).

Identifies what lives at an Ethereum address: EOA wallet, EIP-7702 delegation, or contract, including token standard, name/symbol, proxy info, bytecode size, nonce, and ETH balance.

## Facts

- Endpoint: GET https://ca-tax-api-mainnet.lxtap.workers.dev/eth/contract?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/ethereum-onchain-data-address-type-contract-metadata-725bd07f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_I1beQ36pGaq8I1vY1z_4z

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 ethereum-onchain-data-address-type-contract-metadata-725bd07f
```

Example prompt: Can you look up what's at Ethereum address 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 — tell me whether it's a wallet or contract, what token standard it uses, its name and symbol, and whether it's an upgradeable proxy?

## When to prefer this

Use this endpoint when you need a comprehensive identity snapshot of any Ethereum mainnet address — especially when you need to distinguish EOAs from contracts, detect token standards, discover proxy patterns, or pull balance/nonce in a single call. Prefer this over raw RPC calls when you want normalized, human-readable output without building your own multicall logic.

## Known failure modes

- Invalid address format (not matching ^0x[0-9a-fA-F]{40}$) returns a validation error
- Address not found or zero-activity address may return minimal data with null fields
- RPC/node connectivity issues may cause timeouts or 5xx errors
- Rate limiting or payment failure returns 402 or 429 errors
- Newly deployed contracts may not yet be indexed

## How this service works

Pay-per-call data for AI agents, paid in USDC on Base with x402: token risk checks (rug check) on Base, Ethereum, Arbitrum, Optimism, Polygon and Solana, onchain reads (balances, transactions, gas, contracts, NFTs, whale trades, new pools, ENS and Basenames), ECB exchange rates, and Canadian sales tax and business days.

## Output

Returns a structured object describing the address type (EOA or contract, including EIP-7702 delegation status), the token standard it implements (ERC-20, ERC-721, ERC-1155 or none), the contract's name and symbol where available, upgradeable proxy implementation address and admin, smart-wallet proxy details, bytecode size in bytes, the address's current nonce, and its ETH balance.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string",
       "pattern": "^0x[0-9a-fA-F]{40}$",
       "description": "Any address on Ethereum"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "kind": "ERC-20 token",
  "name": "USD Coin",
  "chain": "eth",
  "proxy": {
   "admin": "0x807a96288A1A408dBC13DE2b1d087d10356395d2",
   "upgradeable": true,
   "implementation": "0x43506849D7C04F9138D1A2050bbF3A0c054402dd"
  },
  "symbol": "USDC",
  "address": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
  "decimals": 6,
  "standards": {
   "erc20": true,
   "erc165": false,
   "erc721": false,
   "erc1155": false
  },
  "isContract": true,
  "totalSupply": "48016325237.499139",
  "bytecodeBytes": 2186,
  "nativeBalance": "0"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/ethereum-onchain-data-address-type-contract-metadata-725bd07f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ca-tax-api-mainnet.lxtap.workers.dev](https://www.zero.xyz/host/ca-tax-api-mainnet.lxtap.workers.dev/llms.txt)