Contract Auditor MCP Server

contract-auditor 🛡️

Quick-scan a smart contract for rug / honeypot / centralization risk before you approve or send funds.

contract-auditor is an MCP server and a pay-per-call x402 HTTP API. Give it a deployed contract address + chain (or raw Solidity source) and it returns a SAFE / CAUTION / HIGH-RISK verdict with an explained risk score.

It combines three things an AI agent can't gather on its own from a chat:

1. Verified source from Sourcify (key-less, multi-chain) — or the absence of it (a strong red flag).
2. Live on-chain state via public RPC — is there code at all? Is it an upgradeable proxy (owner can swap the code)? Who is the owner, and is it a single EOA, a multisig, or renounced?
3. Heuristic Solidity scan for the real ways a contract takes or freezes your funds.

⚠️ Heuristic quick-scan, not a formal audit. Absence of findings is not proof of safety. Always do your own research before sending funds.

What it catches

Use as an MCP server (free)

{
  "mcpServers": {
    "contract-auditor": { "command": "npx", "args": ["-y", "contract-auditor-mcp"] }
  }
}

Tool: audit_contract — params: address, chain (alias or chainId), source (optional raw Solidity), deep (boolean).

Or connect over HTTP at POST /mcp.

Free HTTP API

GET https://contract-auditor-ivory.vercel.app/audit?address=0xdAC17F958D2ee523a2206206994597C13D831ec7&chain=ethereum
GET https://contract-auditor-ivory.vercel.app/audit?address=0x...&chain=base

Supported chains: ethereum, base, optimism, arbitrum, polygon, bsc, avalanche, gnosis, celo (or a numeric chainId). Free tier is rate-limited to 30 requests/hour/IP.

Pay-per-call (x402)

The /pro/audit route is gated by x402. Your agent pays $0.25 USDC per call automatically — no sign-up, no API key — settling on-chain (USDC on Base) to the operator wallet.

GET /pro/audit?address=0x...&chain=ethereum   # 402 → pay → result

How it works (honest about the limits)

• Source is fetched from Sourcify by (chainId, address). If a contract is only verified on a native explorer and not mirrored to Sourcify, it shows as unverified here — pass the source directly to scan it.
• On-chain checks use public RPCs (best-effort, community endpoints). If a chain's RPC is briefly down the audit degrades to a source-only verdict.
• The Solidity scan is static pattern/heuristic analysis with comment-stripping and owner-gating context. It is tuned for low false-alarm on well-known patterns, but it is not symbolic execution or a formal verifier.

License

MIT