# Smart Contract Source Code Lookup

> Smart Contract Source Code Lookup is a paid API for AI agents from x402helper.xyz, paid per call via x402, $0.026/call, status unknown (last checked 2026-10-31).

Fetches the verified source code and metadata for a smart contract at a given address on an EVM network

## Facts

- Endpoint: GET https://x402helper.xyz/89e509/contract/source?utm_source=zero.xyz
- Price: $0.026/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/smart-contract-source-code-lookup-593bad20
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KBDsUSoYMQhkk0Wi6pHZD

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 smart-contract-source-code-lookup-593bad20
```

Example prompt: Can you pull up the verified source code for the smart contract at 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on Ethereum?

## When to prefer this

Use this endpoint when you need to programmatically retrieve verified smart contract source code and metadata for a given address on a supported EVM network (Base, Ethereum, Arbitrum, Optimism, Polygon, BNB). Prefer this when you need quick on-demand contract inspection without setting up a full blockchain node or managing API keys for Etherscan/Sourcify directly.

## Known failure modes

- Contract address not verified on the specified network — returns empty or error result
- Invalid contract address format (must be 0x + 40 hex characters)
- Unsupported network specified
- Contract exists but source code not publicly verified
- Payment failure via x402 micropayment protocol

## How this service works

X402 micropayments server — AI agents pay USDC for OFAC screening, rates, and billing verification.

## Output

Returns a JSON object containing the verified source code, contract name, compiler version, ABI, and other metadata for the specified smart contract address on the requested EVM network. Success flag indicates whether the contract was found and is verified.

## 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",
       "default": null,
       "description": "Contract address, 0x + 40 hex"
      },
      "network": {
       "enum": [
        "base",
        "ethereum",
        "arbitrum",
        "optimism",
        "polygon",
        "bnb"
       ],
       "type": "string",
       "default": null,
       "description": "EVM network (default base)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {},
  "success": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/smart-contract-source-code-lookup-593bad20/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402helper.xyz](https://www.zero.xyz/host/x402helper.xyz/llms.txt)