Copilot CLI Session Notifier

A Windows system tray application that monitors GitHub Copilot CLI sessions and shows popup notifications when sessions need your attention.

Note: This application was fully vibecoded.

Features

• 🔔 Real-time notifications — Get notified when a Copilot CLI session:
  • ⏳ Finishes its turn and waits for your input
  • ✅ Completes and shuts down
  • 🔔 Finishes a background task
• 📌 Persistent popups — Notifications stay in the lower-right corner until you dismiss them
• 🖱️ Click to focus — Click a notification to bring the terminal window to the foreground
• 🌙 Light & dark theme — Automatically matches your Windows theme setting
• ⚡ Auto-start — Optional Windows startup registration
• 📋 Active sessions list — Right-click the tray icon to see all running sessions

How It Works

The app monitors ~/.copilot/session-state/*/events.jsonl files using a combination of:

• FileSystemWatcher for instant detection of new events
• Periodic polling (every 3 seconds) as a reliable fallback

Only new events are processed — the app tracks file read positions and never re-notifies on the same event.

Requirements

• Windows 10/11
• .NET 10 Runtime (or SDK to build from source)
• GitHub Copilot CLI installed and used (creates the session-state directory)

Build & Run

# Build
dotnet build CopilotNotifier\CopilotNotifier.csproj

# Run
dotnet run --project CopilotNotifier\CopilotNotifier.csproj

Publish as Standalone Executable

dotnet publish CopilotNotifier\CopilotNotifier.csproj -c Release -r win-x64

The executable will be in CopilotNotifier\bin\Release\net10.0-windows\win-x64\publish\.

Settings

Right-click the tray icon → Settings (or double-click the icon):

Setting	Description
Notify on waiting for input	Show popup when agent finishes its turn
Notify on session complete	Show popup when session shuts down
Notify on task complete	Show popup when a background task finishes
Play notification sound	Play Windows notification sound
Start with Windows	Register in Windows startup (HKCU Run key)

Settings are saved to %APPDATA%\CopilotNotifier\settings.json.

Architecture

CopilotNotifier/
├── Models/
│   ├── SessionEvent.cs       # Parsed event from events.jsonl
│   ├── SessionInfo.cs        # Tracked session state
│   └── NotificationItem.cs   # Notification display data
├── Services/
│   ├── EventParser.cs        # JSON line parser for events.jsonl
│   ├── SessionWatcher.cs     # FileSystemWatcher + poll timer
│   ├── SessionStateTracker.cs# Track sessions, detect events, dedup
│   ├── WindowFocusService.cs # Win32 P/Invoke to focus terminal
│   ├── AutoStartService.cs   # Windows registry startup management
│   ├── ThemeService.cs       # System light/dark theme detection
│   └── AppSettings.cs        # Settings persistence
├── UI/
│   ├── NotificationPopup.xaml # Custom notification window
│   ├── NotificationManager.cs # Popup stacking and lifecycle
│   └── SettingsWindow.xaml    # Settings dialog
├── App.xaml                   # Application entry point
└── Resources/
    └── app.ico                # Tray icon