# Contract ABI Lookup via Sourcify

> Contract ABI Lookup via Sourcify is a paid API for AI agents from abi.cyberwarex.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Fetch a verified smart contract's ABI, metadata, function/event signatures, and proxy detection for a given address across 7 EVM chains — no API key required.

## Facts

- Endpoint: GET https://abi.cyberwarex.com/abi
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/contract-abi-lookup-via-sourcify-05369e7d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MQV1U-0JupzlaheCDMaYH

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 contract-abi-lookup-via-sourcify-05369e7d
```

Example prompt: Can you pull the verified ABI and function signatures for the contract at 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on Ethereum? Also tell me if it's a proxy and what the implementation address is.

## When to prefer this

Choose this endpoint when you need a smart contract's ABI on any of the 7 supported EVM chains without holding an Etherscan or similar block explorer API key. It's ideal for agents operating keylessly via x402 micropayments, and adds value over raw Sourcify access by also returning parsed function/event signature lists, contract name, compiler info, and proxy detection in one call.

## Known failure modes

- Contract not verified on Sourcify — returns unverified or empty result
- Invalid address format — 400 error if address doesn't match 0x + 40 hex pattern
- Unsupported chain — only base, ethereum, arbitrum, optimism, polygon, bsc, avalanche are valid
- Payment failure — x402 micropayment not processed correctly
- Network timeout — Sourcify upstream may be slow or unavailable

## How this service works

Fetch a verified contract's ABI and metadata by address, keylessly, from Sourcify. Returns the ABI plus a summarized list of function and event signatures, the contract name and compiler, and proxy detection (is_proxy + implementation address). Block explorers gate the ABI behind an API key; this does not. Chains: base, ethereum, arbitrum, optimism, polygon, bsc, avalanche. No API keys, no LLM, one x402 USDC micropayment per call.

## Output

Returns a JSON object containing: the full ABI array, the contract name and compiler version, the chain and address, a list of human-readable function signatures, a list of event signatures, the number of ABI entries, whether the contract is verified on Sourcify, the match type (exact_match or match), whether the contract is a proxy, and the implementation address if applicable.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "chain": {
       "enum": [
        "arbitrum",
        "avalanche",
        "base",
        "bsc",
        "ethereum",
        "optimism",
        "polygon"
       ],
       "type": "string",
       "description": "EVM chain (default base)."
      },
      "address": {
       "type": "string",
       "pattern": "^0x[a-fA-F0-9]{40}$",
       "description": "Contract address (0x + 40 hex chars, required)."
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "abi": {
       "type": "array",
       "description": "the full ABI (JSON array)."
      },
      "name": {
       "type": [
        "string",
        "null"
       ]
      },
      "chain": {
       "type": "string"
      },
      "match": {
       "type": [
        "string",
        "null"
       ],
       "description": "exact_match or match."
      },
      "events": {
       "type": "array",
       "items": {
        "type": "string"
       }
      },
      "source": {
       "type": "string"
      },
      "address": {
       "type": "string"
      },
      "compiler": {
       "type": [
        "string",
        "null"
       ]
      },
      "is_proxy": {
       "type": "boolean"
      },
      "verified": {
       "type": "boolean",
       "description": "true if Sourcify has verified source."
      },
      "functions": {
       "type": "array",
       "items": {
        "type": "string"
       }
      },
      "abi_entries": {
       "type": "integer"
      },
      "implementation": {
       "type": [
        "string",
        "null"
       ],
       "description": "logic address if proxy."
      }
     }
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/contract-abi-lookup-via-sourcify-05369e7d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from abi.cyberwarex.com](https://www.zero.xyz/host/abi.cyberwarex.com/llms.txt)