Peekaboo MCP Server

A macOS utility exposed via Node.js MCP server for advanced screen captures, image analysis, and window management.

🚀 Installation

Prerequisites

• macOS 12.0+ (Monterey or later)
• Node.js 18.0+

Quick Start

Add Peekaboo to your Claude Desktop configuration:

1. Open Claude Desktop settings
2. Go to the Developer tab
3. Edit the configuration file and add:

{
  "mcpServers": {
    "peekaboo": {
      "command": "npx",
      "args": [
        "-y",
        "@steipete/peekaboo-mcp@beta"
      ]
    }
  }
}

4. Restart Claude Desktop

That's it! Peekaboo will be automatically installed and available.

🔧 Configuration

Environment Variables

You can configure Peekaboo with environment variables in your Claude Desktop configuration:

{
  "mcpServers": {
    "peekaboo": {
      "command": "npx",
      "args": [
        "-y",
        "@steipete/peekaboo-mcp@beta"
      ],
      "env": {
        "AI_PROVIDERS": "[{\"type\":\"ollama\",\"baseUrl\":\"http://localhost:11434\",\"model\":\"llava\",\"enabled\":true}]",
        "LOG_LEVEL": "INFO",
        "PEEKABOO_LOG_FILE": "/tmp/peekaboo-mcp.log",
        "PEEKABOO_DEFAULT_SAVE_PATH": "~/Pictures/Screenshots"
      }
    }
  }
}

Available Environment Variables

Variable	Description	Default
AI_PROVIDERS	JSON array of AI provider configurations	[]
LOG_LEVEL	Logging level (DEBUG, INFO, WARN, ERROR)	INFO
PEEKABOO_LOG_FILE	Log file path	/tmp/peekaboo-mcp.log
PEEKABOO_DEFAULT_SAVE_PATH	Default screenshot save location	~/Pictures/Screenshots

AI Provider Configuration

Configure AI providers for image analysis:

[
  {
    "type": "ollama",
    "baseUrl": "http://localhost:11434",
    "model": "llava",
    "enabled": true
  },
  {
    "type": "openai",
    "apiKey": "your-openai-api-key",
    "model": "gpt-4-vision-preview",
    "enabled": false
  }
]

🔐 Permissions Setup

Peekaboo requires specific macOS permissions to function properly:

1. Screen Recording Permission

Grant permission via System Preferences:

1. Open System Preferences → Security & Privacy → Privacy
2. Select Screen Recording from the left sidebar
3. Click the lock icon and enter your password
4. Click + and add your terminal application or MCP client
5. Restart the application

For common applications:

• Terminal.app: /Applications/Utilities/Terminal.app
• Claude Desktop: /Applications/Claude.app
• VS Code: /Applications/Visual Studio Code.app

2. Accessibility Permission (Optional)

For advanced window management features:

1. Open System Preferences → Security & Privacy → Privacy
2. Select Accessibility from the left sidebar
3. Add your terminal/MCP client application

✅ Verification

Test your installation:

# Test the Swift CLI directly
./peekaboo --help

# Test server status
./peekaboo list server_status --json-output

# Test screen capture (requires permissions)
./peekaboo image --mode screen --format png

# Start the MCP server for testing
peekaboo-mcp

Expected output for server status:

{
  "success": true,
  "data": {
    "swift_cli_available": true,
    "permissions": {
      "screen_recording": true
    },
    "system_info": {
      "macos_version": "14.0"
    }
  }
}

🎯 Quick Start

Once installed and configured:

1. Capture Screenshot:

   peekaboo-mcp
   # In your MCP client: "Take a screenshot of my screen"
   

2. List Applications:

   # In your MCP client: "Show me all running applications"
   

3. Analyze Screenshot:

   # In your MCP client: "Take a screenshot and tell me what's on my screen"

🐛 Troubleshooting

Common Issues:

Issue	Solution
Permission denied errors	Grant Screen Recording permission in System Preferences
Swift CLI unavailable	Rebuild Swift CLI: cd swift-cli && swift build -c release
AI analysis failed	Check AI provider configuration and network connectivity
Command not found: peekaboo-mcp	Run npm link or check global npm installation

Debug Mode:

# Enable verbose logging
LOG_LEVEL=DEBUG peekaboo-mcp

# Check permissions
./peekaboo list server_status --json-output

Get Help:

• 📚 Documentation
• 🐛 Issues
• 💬 Discussions

📦 Alternative Installation Methods

From Source

If you want to build from source or contribute to development:

# Clone the repository
git clone https://github.com/steipete/peekaboo.git
cd peekaboo

# Install Node.js dependencies
npm install

# Build the TypeScript server
npm run build

# Build the Swift CLI component
cd swift-cli
swift build -c release

# Copy the binary to the project root
cp .build/release/peekaboo ../peekaboo

# Return to project root
cd ..

# Optional: Link for global access
npm link

Then configure Claude Desktop to use your local installation:

{
  "mcpServers": {
    "peekaboo": {
      "command": "peekaboo-mcp",
      "args": []
    }
  }
}

Using AppleScript

For basic screen capture without the full MCP server, you can use the included AppleScript:

# Run the AppleScript directly
osascript peekaboo.scpt

This provides a simple way to capture screenshots but doesn't include the MCP integration or AI analysis features.

Manual Configuration for Other MCP Clients

For MCP clients other than Claude Desktop:

{
  "server": {
    "command": "node",
    "args": ["/path/to/peekaboo/dist/index.js"],
    "env": {
      "AI_PROVIDERS": "[{\"type\":\"ollama\",\"baseUrl\":\"http://localhost:11434\",\"model\":\"llava\",\"enabled\":true}]"
    }
  }
}

---

🛠️ Available Tools

Once installed, Peekaboo provides three powerful MCP tools:

📸 peekaboo.image - Screen Capture

Parameters:

• mode: "screen" | "window" | "multi" (default: "screen")
• app: Application identifier for window/multi modes
• path: Custom save path (optional)

Example:

{
  "name": "peekaboo.image", 
  "arguments": {
    "mode": "window",
    "app": "Safari"
  }
}

📋 peekaboo.list - Application Listing

Parameters:

• item_type: "running_applications" | "application_windows" | "server_status"
• app: Application identifier (required for application_windows)

Example:

{
  "name": "peekaboo.list",
  "arguments": {
    "item_type": "running_applications"
  }
}

🧩 peekaboo.analyze - AI Analysis

Parameters:

• image_path: Absolute path to image file
• question: Question/prompt for AI analysis

Example:

{
  "name": "peekaboo.analyze",
  "arguments": {
    "image_path": "/tmp/screenshot.png",
    "question": "What applications are visible in this screenshot?"
  }
}

🎯 Key Features

Screen Capture

• Multi-display support: Captures each display separately
• Window targeting: Intelligent app/window matching with fuzzy search
• Format flexibility: PNG, JPEG, WebP, HEIF support
• Automatic naming: Timestamps and descriptive filenames
• Permission handling: Automatic screen recording permission checks

Application Management

• Running app enumeration: Complete system application listing
• Window discovery: Per-app window enumeration with metadata
• Fuzzy matching: Find apps by partial name, bundle ID, or PID
• Real-time status: Active/background status, window counts

AI Integration

• Provider agnostic: Support for Ollama, OpenAI, and other providers
• Image analysis: Natural language querying of captured content
• Configurable: Environment-based provider selection

🏛️ Project Structure

Peekaboo/
├── src/                      # Node.js MCP Server (TypeScript)
│   ├── index.ts             # Main MCP server entry point
│   ├── tools/               # Individual tool implementations
│   │   ├── image.ts         # Screen capture tool
│   │   ├── analyze.ts       # AI analysis tool  
│   │   └── list.ts          # Application/window listing
│   ├── utils/               # Utility modules
│   │   ├── swift-cli.ts     # Swift CLI integration
│   │   ├── ai-providers.ts  # AI provider management
│   │   └── server-status.ts # Server status utilities
│   └── types/               # Shared type definitions
├── swift-cli/               # Native Swift CLI
│   └── Sources/peekaboo/    # Swift source files
│       ├── main.swift       # CLI entry point
│       ├── ImageCommand.swift    # Image capture implementation
│       ├── ListCommand.swift     # Application listing
│       ├── Models.swift          # Data structures
│       ├── ApplicationFinder.swift   # App discovery logic
│       ├── WindowManager.swift      # Window management
│       ├── PermissionsChecker.swift # macOS permissions
│       └── JSONOutput.swift        # JSON response formatting
├── package.json             # Node.js dependencies
├── tsconfig.json           # TypeScript configuration
└── README.md               # This file

🔧 Technical Details

Swift CLI JSON Output

The Swift CLI outputs structured JSON when called with --json-output:

{
  "success": true,
  "data": {
    "applications": [
      {
        "app_name": "Safari",
        "bundle_id": "com.apple.Safari", 
        "pid": 1234,
        "is_active": true,
        "window_count": 2
      }
    ]
  },
  "debug_logs": ["Found 50 applications"]
}

MCP Integration

The Node.js server translates between MCP's JSON-RPC protocol and the Swift CLI's JSON output, providing:

• Schema validation via Zod
• Error handling with proper MCP error codes
• Logging via Pino logger
• Type safety throughout the TypeScript codebase

Permission Model

Peekaboo respects macOS security by:

• Checking screen recording permissions before capture operations
• Graceful degradation when permissions are missing
• Clear error messages guiding users to grant required permissions

🧪 Testing

Manual Testing

# Test Swift CLI directly
./peekaboo list apps --json-output | head -20

# Test MCP integration  
echo '{"jsonrpc": "2.0", "id": 1, "method": "tools/list"}' | node dist/index.js

# Test image capture
echo '{"jsonrpc": "2.0", "id": 2, "method": "tools/call", "params": {"name": "peekaboo.image", "arguments": {"mode": "screen"}}}' | node dist/index.js

Automated Testing

# TypeScript compilation
npm run build

# Swift compilation  
cd swift-cli && swift build

🐛 Known Issues

• FileHandle warning: Non-critical Swift warning about TextOutputStream conformance
• AI Provider Config: Requires AI_PROVIDERS environment variable for analysis features

🚀 Future Enhancements

• OCR Integration: Built-in text extraction from screenshots
• Video Capture: Screen recording capabilities
• Annotation Tools: Drawing/markup on captured images
• Cloud Storage: Direct upload to cloud providers
• Hotkey Support: System-wide keyboard shortcuts

📄 License

MIT License - see LICENSE file for details.

🤝 Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Commit your changes (git commit -m 'Add amazing feature')
4. Push to the branch (git push origin feature/amazing-feature)
5. Open a Pull Request

---

🎉 Peekaboo is ready to use! The project successfully combines the power of native macOS APIs with modern Node.js tooling to create a comprehensive screen capture and analysis solution.