SnapBack MCP Server

Give your AI agent access to SnapBack's pattern memory.

Query what's broken before, get warnings about risky patterns, and let your agent learn from 1,000+ repos' mistakes.

Quick Start

npm install -g @snapback/mcp-server
snapback-mcp

Works immediately - no configuration required!

What It Does

🆓 Free (No Account Needed)

• ✅ Pattern Memory Queries: "Has this refactor pattern caused problems before?"
• ✅ Risk Assessment: Check if changes match known failure patterns
• ✅ Dependency Checking: Validate package.json changes
• ✅ Offline Ready: Works without internet connection

☁️ Pro Features (Optional API Key)

Add SNAPBACK_API_KEY to unlock:

• 🔐 Report Outcomes: Tell SnapBack what actually broke (improves future detection)
• 🔐 Create Snapshots: Let your AI agent checkpoint before risky refactors
• 🔐 Cloud Sync: Access snapshots across devices
• 🔐 Team Sharing: Share learned patterns with teammates

Installation

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "snapback": {
      "command": "npx",
      "args": ["-y", "@snapback/mcp-server"]
    }
  }
}

With API Key (Optional)

{
  "mcpServers": {
    "snapback": {
      "command": "npx",
      "args": ["-y", "@snapback/mcp-server"],
      "env": {
        "SNAPBACK_API_KEY": "your_api_key_here"
      }
    }
  }
}

Cursor / Other MCP Clients

# Install globally
npm install -g @snapback/mcp-server

# Run with stdio transport
snapback-mcp

Available Tools

snapback.analyze_risk

Analyze code changes for potential security risks before applying them.

When to use:

• Before accepting AI-generated code
• When reviewing complex changes
• For critical files (auth, database, config)

Example:

// AI detects you want to add authentication
// Before applying changes, it calls:
snapback.analyze_risk({
  changes: [
    { added: true, value: "const API_KEY = 'sk_live_...';" }
  ]
})
// Returns: ⚠️ HIGH RISK: Hardcoded secret detected

snapback.check_dependencies

Check for dependency-related risks when package.json changes.

Example:

snapback.check_dependencies({
  before: { "lodash": "^4.17.15" },
  after: { "lodash": "^4.17.21" }
})
// Returns: ℹ️ Security update available

snapback.create_snapshot (Pro)

Create a code snapshot before risky changes.

Example:

snapback.create_snapshot({
  reason: "Before major refactor",
  files: ["src/auth.ts", "src/db.ts"]
})
// Returns: ✅ Snapshot created: snap_xyz123

snapback.list_snapshots (Pro)

List all available snapshots.

snapback.restore_snapshot (Pro)

Restore code from a previous snapshot.

Context7 Tools

• ctx7.resolve-library-id: Find library documentation
• ctx7.get-library-docs: Fetch library docs and examples

Configuration

Environment Variables

# Optional: SnapBack API key for Pro features
SNAPBACK_API_KEY=sk_...

# Optional: Custom API URL
SNAPBACK_API_URL=https://api.snapback.dev

# Optional: Context7 API key for enhanced docs
CONTEXT7_API_KEY=...

# Optional: Log level
LOG_LEVEL=info

Offline Mode

Works perfectly without any configuration or API keys:

# No env vars needed!
npx @snapback/mcp-server

What works offline:

• Risk analysis (basic)
• Dependency checking
• Secret detection
• Context7 library search (cached)

What requires API key:

• Advanced ML risk analysis
• Snapshot creation/restoration
• Cloud sync
• Team features

Architecture

┌─────────────────┐
│   AI Tool       │  (Claude, Cursor, etc.)
│   (MCP Client)  │
└────────┬────────┘
         │ MCP Protocol
         │
┌────────▼─────────────────────────────────┐
│  SnapBack MCP Server                     │
│  ┌──────────────┐  ┌──────────────────┐ │
│  │ Free Tools   │  │  Pro Tools       │ │
│  │ - analyze    │  │  - snapshots     │ │
│  │ - check_deps │  │  - cloud sync    │ │
│  └──────────────┘  └──────────────────┘ │
└───────────┬──────────────────────────────┘
            │
        ┌───┴────┐
        │        │
   ┌────▼───┐ ┌─▼─────────┐
   │ Local  │ │ SnapBack  │
   │Analysis│ │    API    │
   └────────┘ └───────────┘

Development

Running Locally

git clone https://github.com/snapback-dev/mcp-server.git
cd mcp-server

pnpm install
pnpm build
pnpm start

Testing

# Run tests
pnpm test

# Test without API key (offline mode)
unset SNAPBACK_API_KEY
pnpm start

# Test with API key
export SNAPBACK_API_KEY=sk_test_...
pnpm start

Building

pnpm build

# Output: dist/index.js (ESM)

Troubleshooting

Server won't start

1. Check Node.js version: node -v (requires 18+)
2. Clear cache: rm -rf node_modules && npm install
3. Check permissions: chmod +x $(which snapback-mcp)

API key not working

1. Verify key format: sk_live_... or sk_test_...
2. Check env var: echo $SNAPBACK_API_KEY
3. Get new key: snapback.dev/settings/api

Tools not showing in Claude

1. Restart Claude Desktop completely
2. Check config file syntax (JSON must be valid)
3. Look for errors in Claude's console logs

Security

• All secrets handled via environment variables
• No data sent to SnapBack without API key
• Local analysis runs offline
• Open source - audit the code yourself

Report security issues: [email protected]

Links

• Documentation: docs.snapback.dev
• Main Repository: Marcelle-Labs/snapback.dev
• Issues: github.com/snapback-dev/mcp-server/issues
• NPM: @snapback/mcp-server

License

Apache-2.0 © SnapBack

Related

• snapback VS Code Extension
• @snapback/sdk - TypeScript SDK
• @snapback/contracts - Type definitions