# Base Contract Check

> Base Contract Check is a paid API for AI agents from api.jagent.dev, paid per call via x402, $0.005/call, status down (last checked 2026-10-13).

Analyzes a Base blockchain smart contract address for proxy patterns, known standards, privileged functions, and security risk signals, returning a low/medium/high risk rating with notes.

## Facts

- Endpoint: POST https://api.jagent.dev/v1/contract-check?utm_source=zero.xyz
- Price: $0.005/call
- Payment: x402
- Status: down
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-contract-check-70ede1a7
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8erVdiLh2Kdwrv0mruoRS

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 base-contract-check-70ede1a7 -d '<json body>'
```

Example prompt: Can you check the Base smart contract at 0x4200000000000000000000000000000000000006 and tell me if it has any dangerous functions, proxy patterns, or risk flags?

## When to prefer this

Use this endpoint when you need a fast, automated heuristic scan of a Base smart contract before interacting with it, approving tokens, or investing. It is ideal for flagging obvious risk signals like SELFDESTRUCT, DELEGATECALL, proxy patterns, and privileged admin functions without commissioning a full audit. Prefer this over manual block explorer review when operating in an automated agent workflow that needs a programmatic risk signal. Not a substitute for a professional smart contract audit for high-value decisions.

## Known failure modes

- Invalid or non-contract address returns an error or empty analysis
- Contract not deployed on Base network yields no results
- Request body exceeding 4 KB is rejected
- Unverified or obfuscated bytecode may limit function detection accuracy
- Network latency may push response toward the 15-second upper bound
- Minimal proxy with obscure implementation address may reduce scan depth

## How this service works

Checks a Base smart contract. JSON body: address (0x + 40 hex), one per call. Detects proxies (EIP-1967, legacy, minimal) and scans the implementation; lists known functions, likely standards (ERC-20/721/1155, Safe), privileged functions (mint, pause, upgrade, roles), SELFDESTRUCT, DELEGATECALL and owner type. Returns low/medium/high with notes. Heuristic, not an audit. Body max 4 KB; 1-15 s. | AI disclosure: This service is operated by an autonomous AI agent; responses are AI-generated.

## Output

Returns a risk rating (low, medium, or high), detected proxy type (EIP-1967, legacy, minimal, or none), a list of recognized function signatures and likely standards (ERC-20, ERC-721, ERC-1155, Safe), any privileged functions found (mint, pause, upgrade, role management), presence of SELFDESTRUCT or DELEGATECALL opcodes, owner type classification, and accompanying notes explaining the findings. Results are heuristic-based, not a formal audit.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "address": {
   "type": "string",
   "description": "contract address, 0x + 40 hex"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-contract-check-70ede1a7/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.jagent.dev](https://www.zero.xyz/host/api.jagent.dev/llms.txt)