JEP Snap for MetaMask

🛡️ Protect your assets from malicious transactions with verifiable JEP receipts

✨ Features

| Feature | Description | |---------|-------------| | 🛡️ Transaction Risk Analysis | Automatically detects high-risk transactions before you sign | | ✅ User Confirmation | Shows clear warnings with risk levels (low/medium/high) | | 🔐 JEP Receipts | Generates verifiable, cryptographically signed receipts for every transaction | | 📝 Audit Log | Stores all transaction receipts locally in your MetaMask | | 🔍 Export Evidence | Retrieve receipts anytime as proof of transaction approval |

🚀 Why You Need This

In 2025 alone, users lost over $4.4 billion to malicious transactions.

JEP Snap adds a security layer between you and every transaction:

1. Analyzes each transaction for risk
2. Warns you if something looks suspicious
3. Records every approval as verifiable evidence
4. Protects you from signing away your assets

📥 Installation

Method 1: From MetaMask Snaps Directory (Recommended)

1. Open MetaMask
2. Go to Settings → Snaps
3. Search for "JEP Guard"
4. Click Install

Method 2: Direct Link

Visit MetaMask Snaps Directory and click "Add to MetaMask"

Method 3: Development Installation

# Clone repository
git clone https://github.com/jep-eth/jep-snap.git
cd jep-snap/packages/snap

# Install dependencies
npm install

# Build and test locally
npm run build
npm run serve

🔧 How It Works

When you initiate a transaction, JEP Snap:

1. Analyzes the destination address and function call
2. Checks against known malicious patterns
3. Shows a risk assessment dialog
4. Records your decision as a verifiable JEP receipt
5. Stores the receipt for future reference

Risk Levels

| Level | Color | Action | |-------|-------|--------| | Low | 🟢 Green | Normal transaction, logged automatically | | Medium | 🟡 Yellow | Shows warning, requires confirmation | | High | 🔴 Red | Shows urgent warning, requires explicit approval |

📊 Example Receipt

{
  "version": "1.0",
  "timestamp": "2026-03-11T14:30:00Z",
  "transaction": {
    "to": "0x1234...",
    "value": "1.5 ETH",
    "function": "approve"
  },
  "risk": "medium",
  "approved": true,
  "receiptHash": "0x7f83b1657ff1fc53b92dc18148a1d65dfc2d4b1fa3d677284addd200126d9069"
}

🔐 Security

• No private keys - Your keys never leave MetaMask
• Local storage - All receipts stored in your local MetaMask state
• Open source - Fully auditable code
• JEP Protocol - Based on IETF Internet-Draft standard

📄 License

MIT © JEP Foundation

🔗 Links

• GitHub: https://github.com/jep-eth/jep-snap
• JEP Protocol: https://github.com/hjs-spec/jep-spec
• IETF Draft: https://datatracker.ietf.org/doc/draft-wang-hjs-judgment-event/

🤝 Contributing

Issues and PRs welcome! See CONTRIBUTING.md for guidelines.