# Polygon PoS Address Inspector

> Polygon PoS Address Inspector is a paid API for AI agents from onchaincheck.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-29).

Identifies what lives at a Polygon PoS address: EOA vs contract, token standard (ERC-20/721/1155), name, symbol, proxy details, bytecode size, nonce, and POL balance.

## Facts

- Endpoint: GET https://onchaincheck.dev/polygon/contract?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/polygon-pos-address-inspector-eb88428b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_cVahingigpILnlv12CBQO

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 polygon-pos-address-inspector-eb88428b
```

Example prompt: Can you tell me what the address 0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359 is on Polygon PoS — is it a wallet or a contract, and if it's a token what's its name, symbol, and whether it's an upgradeable proxy?

## When to prefer this

Use this endpoint when you need a comprehensive onchain profile of any Polygon PoS address in a single call — covering wallet vs contract classification, token standard detection, proxy architecture, and native balance. Prefer it over block explorer manual lookups or raw RPC calls when you need structured, agent-readable output. Choose this over Ethereum or Base equivalents when the target address is on Polygon PoS specifically.

## Known failure modes

- Invalid address format (not a 0x 40-hex-char address) returns a validation error
- Address not found or zero-address may return minimal or empty data
- RPC timeout or Polygon node unavailability may cause 5xx errors
- Non-standard or exotic proxy patterns may not be detected as upgradeable
- EIP-7702 delegation may not be detected on older contract deployments

## How this service works

Identify what lives at a Polygon PoS address: wallet (EOA, including EIP-7702 delegation) or contract, which token standard it implements (ERC-20, ERC-721, ERC-1155), name and symbol, upgradeable-proxy implementation and admin, smart-wallet proxies, bytecode size, nonce and POL balance.

## Output

A JSON object containing: the address kind (e.g. 'ERC-20 token', 'EOA', 'smart wallet'), chain identifier ('polygon'), token name and symbol, decimals, total supply, proxy details (upgradeable flag, implementation address, admin address), boolean flags for each ERC standard (ERC-20, ERC-165, ERC-721, ERC-1155), isContract flag, bytecode size in bytes, and native POL 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 Polygon PoS"
      }
     },
     "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": "polygon",
  "proxy": {
   "admin": "0x9238E612387eBBA4D4Fa0d76DbFbA99b453417b3",
   "upgradeable": true,
   "implementation": "0x235AE97b28466Db30469b89A9fe4cFf0659f82Cb"
  },
  "symbol": "USDC",
  "address": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
  "decimals": 6,
  "standards": {
   "erc20": true,
   "erc165": false,
   "erc721": false,
   "erc1155": false
  },
  "isContract": true,
  "totalSupply": "586295089.86576",
  "bytecodeBytes": 1852,
  "nativeBalance": "0"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/polygon-pos-address-inspector-eb88428b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from onchaincheck.dev](https://www.zero.xyz/host/onchaincheck.dev/llms.txt)