# SYNTHORA Contract Guard (contract_guard)

> SYNTHORA Contract Guard (contract_guard) is a paid API for AI agents from contract-guard.hergertsynthora.com, paid per call via x402, $0.32/call, status unknown (last checked 2026-09-14).

Analyzes a smart contract address on-chain — reading bytecode, proxy slots, and ownership — to produce a signed security verdict flagging honeypots, rug-pull vectors, hidden mints, and upgradeable proxy risks.

## Facts

- Endpoint: POST https://contract-guard.hergertsynthora.com/service
- Price: $0.32/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/synthora-contract-guard-contract-guard-70678266
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CttlAKXwLrKjYFSurqCeg

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 synthora-contract-guard-contract-guard-70678266 -d '<json body>'
```

Example prompt: Can you run a security audit on the smart contract at 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 on Base — I need to know if it's a proxy, who owns it, and whether there are any honeypot or rug-pull red flags before I interact with it.

## When to prefer this

Choose this endpoint when you need a signed, multi-source-corroborated security verdict on a specific smart contract — especially when proxy upgradeability, hidden ownership, or honeypot patterns are the concern. It is preferable to generic block explorers when you need machine-readable structured risk flags and cryptographic provenance, and over static analysis tools when you want live on-chain bytecode and storage slot reads (EIP-1967, zeppelinos, UUPS, beacon) combined. Ideal for autonomous DeFi agents that must make trust decisions before executing transactions.

## Known failure modes

- Invalid or non-existent contract address returns an error or empty bytecode result
- Unsupported chain identifier causes a rejection
- Payment header missing or malformed results in HTTP 402 with payment requirements
- EIP-3009 authorization expired or invalid causes payment rejection
- Contract with no deployed code (EOA address) may return a null bytecode flag
- Rate limiting or network congestion on Base RPC may delay or fail the on-chain reads

## How this service works

Aggregate OpenAPI for the SYNTHORA x402 mesh: 121 pay-per-call services, each on its own host under *.hergertsynthora.com, path /service, POST JSON. Per-service OpenAPI: https://<host>/openapi.json. Payment: x402, USDC on Base, payTo 0xEf879BFD6C4AccB8F795136de90246e1EC245e06 (Safe 1.3.0). Full machine catalog: https://catalog.hergertsynthora.com/catalog.json

## Output

A JSON object containing: a verdict string (e.g. 'medium', 'high', 'low' risk), an array of human-readable security flags, the detected proxy standard (e.g. zeppelinos, UUPS, EIP-1967), owner address, whether the contract is verified on Sourcify, a rationale explanation, a disclaimer, and an Ed25519-signed provenance statement corroborated across at least 3 independent sources.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "input": {
   "type": "string",
   "description": "SYNTHORA contract_guard (endpoint canonico historico, alias de contractwatch): veredicto de seguridad de contrato on-chain que SI lee el bytecode (eth_getCode) y slots de proxy (EIP-1967/zeppelinos/UU"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "schema": {
  "type": "object",
  "required": [
   "ok",
   "niche"
  ],
  "properties": {
   "ok": {
    "type": "boolean"
   },
   "error": {
    "type": "string"
   },
   "niche": {
    "type": "string"
   },
   "result": {
    "type": "object",
    "properties": {
     "chain": {
      "type": "string"
     },
     "flags": {
      "type": "array"
     },
     "owner": {
      "type": "string"
     },
     "proxy": {
      "type": "boolean"
     },
     "address": {
      "type": "string"
     },
     "changed": {
      "type": "boolean"
     },
     "changes": {
      "type": "array"
     },
     "verdict": {
      "type": "string"
     },
     "verified": {
      "type": "boolean"
     },
     "rationale": {
      "type": "string"
     },
     "proxy_standard": {
      "type": "string"
     }
    }
   },
   "receipt": {
    "type": "object"
   }
  }
 },
 "example": {
  "ok": true,
  "niche": "contract_guard",
  "result": {
   "chain": "base",
   "flags": [
    "código NO verificado en Sourcify",
    "PROXY actualizable (zeppelinos) — el admin/owner puede cambiar la lógica (impl 0x2Ce6311d…)",
    "..."
   ],
   "owner": "0x3ABd6f64A422225E61E435baE41db12096106df7",
   "proxy": true,
   "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
   "verdict": "medium",
   "verified": false,
   "rationale": "SIN verificar. Proxy actualizable (zeppelinos: riesgo de cambio de lógica). Tiene owner/control centralizado.",
   "disclaimer": "No es consejo financiero. Análisis automatizado de seguridad on-chain con procedencia firmada.",
   "proxy_standard": "zeppelinos"
  },
  "provenance": "<3 fuentes independientes>"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/synthora-contract-guard-contract-guard-70678266/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from contract-guard.hergertsynthora.com](https://www.zero.xyz/host/contract-guard.hergertsynthora.com/llms.txt)