Agent Shield

🛡️ AgentShield

Give your AI a health check.

One scan. Thirteen engines. One report.

[中文文档](./README.zh-CN.md)

You found an MCP Server / Skill / Plugin online and want to install it. But you're wondering:

> Is this thing safe? Will it steal my API keys? Hijack my AI? Mine crypto?

AgentShield answers that in seconds. One command, 13 independent scanning engines, one clear report.

npx @elliotllliu/agent-shield scan ./that-thing-you-want-to-install

That's it. First run auto-installs all engines. After that, results come in seconds.

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See It In Action

🛡️  安全检测报告
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

📁 检测对象:  ./mcp-puppeteer
🔧 检测引擎:  13 个独立扫描器
⏱  总耗时:    50.2s

──────────────────────────────────────────────────────
🔍 各方检测结论
──────────────────────────────────────────────────────

📋 AgentShield — 内置参考（AI Agent 基础检查）
   结论: ⚠️ 发现 1 处需关注
   • 代码混淆  📍 src/index.ts:1

🔍 Aguara — 通用代码安全
   结论: ✅ 未发现风险

🔎 Semgrep — 代码质量与注入检测
   结论: ✅ 未发现风险

🧪 Invariant — MCP Tool Poisoning 检测
   结论: ✅ 未发现风险

🔬 Trivy — 漏洞扫描 + 密钥检测
   结论: ✅ 未发现风险

🔑 Gitleaks — 密钥和 Token 泄露
   结论: ✅ 未发现风险

🐍 Bandit — Python 代码安全
   结论: ✅ 未发现风险

📡 Bearer — 数据流 + 隐私分析
   结论: ✅ 未发现风险

──────────────────────────────────────────────────────
📊 综合结论
──────────────────────────────────────────────────────

✅ 所有引擎均未检出风险
   （7/7 个外部引擎未检出风险）

  ✅ 后门/远程控制  — 7 个引擎均未检出
  ✅ 数据窃取       — 7 个引擎均未检出
  ✅ Prompt 注入    — 7 个引擎均未检出
  ✅ 挖矿行为       — 7 个引擎均未检出

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

One glance: 7 out of 7 external engines say it's clean. All major threats cleared. Safe to install.

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Why Trust It?

Because it's not one engine making the call. It's 13 independent scanning engines, each a specialist in their own domain. We bring them together:

| Engine | What it's best at | |--------|------------------| | 📋 AgentShield (reference) | AI Agent basics — skill hijack, prompt injection, MCP runtime | | 🔍 Aguara | General security — 177 rules, data exfil, taint tracking | | 🔎 Semgrep | Code quality — 2000+ rules, injection, XSS, hardcoded secrets | | 🧪 Invariant | MCP-specific — tool poisoning, cross-origin escalation, rug pull | | 🔬 Trivy | Vulnerability scan + secret detection + SBOM | | 🔑 Gitleaks | Secret and token leak detection | | 🐍 Bandit | Python code security | | 📡 Bearer | Data flow + privacy analysis | | 🐕 TruffleHog | Secret detection + verification if active | | 🌐 OSV-Scanner | Dependency vulnerabilities (Google OSV database) | | 🦑 Grype | Dependency vulnerability scanning | | 🟢 njsscan | Node.js / JavaScript security | | 🔐 detect-secrets | Secret detection (Yelp) |

Each engine has its own strengths. We combine all of them into one report.

The built-in engine is reference-only — the overall conclusion is decided by the 7 external engines' consensus. The stronger they get, the stronger we get.

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First Run

First time you run it, engines are auto-installed (to ~/.agentshield/, no sudo needed):

🔧 检查引擎...
  ✅ AgentShield — 已就绪
  📦 Aguara — 正在安装... 完成
  📦 Semgrep — 正在安装... 完成
  📦 Invariant — 正在安装... 完成
  📦 Trivy — 正在安装... 完成
  📦 Gitleaks — 正在安装... 完成
  📦 Bandit — 正在安装... 完成
  📦 Bearer — 正在安装... 完成

One-time setup. After that, it's instant.

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What Can It Detect?

| Risk | What it means | |------|--------------| | 🔴 Skill Hijack | It's secretly modifying your AI's config | | 🔴 Backdoor | It can silently execute arbitrary code | | 🔴 Remote Control | It's connecting to external servers + opening a shell | | ⚠️ Data Theft | It reads your keys/files and sends them out | | ⚠️ Prompt Injection | It's secretly adding instructions to your AI | | ⚠️ Tool Poisoning | Hidden malicious instructions in tool descriptions | | ⚠️ Obfuscated Code | Code is intentionally unreadable — might be hiding something | | ⚠️ Vulnerabilities | Known CVEs in dependencies | | ⚠️ Secret Leaks | API keys, tokens, passwords in source code | | ℹ️ Excessive Permissions | It asks for more than it needs |

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More Options

# HTML report (shareable)
agent-shield scan ./dir --html -o report.html

# JSON (for CI/CD)
agent-shield scan ./dir --json

# Chinese report (default)
agent-shield scan ./dir --lang zh

# SARIF (GitHub Code Scanning)
agent-shield scan ./dir --sarif -o results.sarif

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Install

# Recommended: use npx, nothing to install
npx @elliotllliu/agent-shield scan ./my-skill/

# Or install globally
npm install -g @elliotllliu/agent-shield

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Our Philosophy

> "We don't compete — we aggregate."

We bring every engine's strengths together, cross-validate their findings, and produce one unified report. The stronger each engine gets, the stronger AgentShield gets.

We're the X-ray machine, not the doctor. We show you what's inside — you decide whether to install it.

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License

MIT

Source & license

This open-source MCP server is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: elliotllliu
• Source: elliotllliu/agent-shield
• License: MIT
• Homepage: https://www.npmjs.com/package/@elliotllliu/agentshield

Install and usage instructions live in the source repository linked above.