Safe Tools

The easiest way to sign and verify messages with your Gnosis Safe. Built for simple, reliable message signing with an authentic retro terminal interface. Features EIP-712 message signing, EIP-1271 verification, and MEW/MyCrypto-compatible output formats.

🚀 Quick Start

Use the Safe App

1. Go to app.safe.global
2. Open the Apps tab in your Safe
3. Click Add Custom App
4. Paste: https://www.safetools.io

Once added, Safe Tools will appear in your Safe's app drawer for easy message signing.

Install CLI Tools

npm install -g safe-message-tools

🎯 What it's for

• Sign messages from your Safe
• Authenticate with apps and services
• Prove Safe ownership onchain or offchain
• Generate verifiable signatures for any use case

🛠️ Usage

Safe App Interface

The web interface provides an authentic retro terminal experience for signing messages directly from your Safe:

• Retro terminal UI: Authentic 80s hacker aesthetic with scanlines and terminal effects
• Simple workflow: Enter any message, approve the Safe transaction, get verifiable results
• Multiple output formats: Standard signature + MEW/MyCrypto-compatible JSON
• Copy-to-clipboard: One-click copying for all signature data and JSON formats
• Multi-signature support: Automatically handles Safe threshold requirements (2/3, 3/5, etc.)
• EIP-1271 verification: Onchain signature validation using Safe's SignMessageLib contract

CLI Tools

For developers and automation:

# Sign with private key
safe-sign --safe 0x... --key 0x... --message "Hello World" --rpc https://...

# Verify signature onchain
safe-verify --safe 0x... --signature 0x... --message "Hello World" --rpc https://... --onchain

# Hardware wallet signing (Ledger)
safe-hw --safe 0x... --message "Hello World" --rpc https://...

# Coordinate multiple signatures  
safe-collect --safe 0x... --message "Hello World" --rpc https://... --sig 0x... --signer 0x...

🏗️ How it works

Safe Tools uses the official Safe SignMessageLib contract and EIP-1271 standard:

1. EIP-712 hashing: Messages are hashed using Safe's domain separator for security
2. Onchain transaction: Creates a transaction to SignMessageLib contract (0xA65387F16B013cf2Af4605Ad8aA5ec25a2cbA3a2)
3. Multi-signature coordination: Safe interface handles threshold requirements automatically
4. Dual output formats: Standard signature + MEW/MyCrypto-compatible JSON for broad compatibility
5. EIP-1271 verification: Onchain signature validation that any service can verify
6. Cross-platform support: Works in Safe Apps interface and as standalone CLI tools

🔧 Development

Repository Structure

├── safe-app/          # Safe App (React + Vite)
├── cli/               # Command-line tools  
├── lib/               # Shared utilities
└── package.json       # CLI package configuration

Local Development

# Clone repository
git clone https://github.com/zscole/safe-message-cli.git
cd safe-message-cli

# Install dependencies
npm run install-all

# Start development server
npm run dev

The Safe App will be available at http://localhost:5174 - add this URL as a custom app in your Safe interface for testing.

Building

# Build Safe App for production
npm run build

# Install CLI tools globally from source
npm install -g .

📋 Output Formats

Standard Signature Output

• Original message text
• Safe address used for signing
• Signature/transaction hash
• EIP-1271 verification status

MEW/MyCrypto-Compatible JSON

{
  "address": "0x9CFe9dc15b6cA16147dF1b93E487bAaDd422F693",
  "msg": "Prove ownership of Safe for domain verification", 
  "sig": "0xbfddd739e0a9a49d6885ccded16267760649505bdd589703cc833364904a9e4c",
  "version": "2"
}

📋 Standards

• EIP-712: Typed data signing with Safe domain separation
• EIP-1271: Onchain signature verification standard
• Safe Apps SDK: Official integration with Safe interface
• MEW/MyCrypto: Compatible JSON signature format
• Browser compatible: No Node.js dependencies in web interface

🛡️ Security

• Uses official Safe SignMessageLib contract (0xA65387F16B013cf2Af4605Ad8aA5ec25a2cbA3a2)
• No custom smart contracts deployed
• All operations require Safe owner approval
• Open source and auditable code

📄 License

MIT License - see LICENSE file for details.

🔗 Links

• Live App: https://www.safetools.io
• Safe Apps: Add as custom app in your Safe interface
• GitHub: https://github.com/zscole/safe-message-cli

Built by Zak Cole at Number Group