# cursor-flasher

A macOS daemon that flashes a pulsing border around Cursor IDE windows when the AI agent is waiting for your input. Optionally plays a system sound.

## Prerequisites

- macOS
- Python 3.10+
- [uv](https://docs.astral.sh/uv/) (recommended)
- **Accessibility permission** granted to your terminal (System Settings → Privacy & Security → Accessibility)

## Installation

```bash
git clone <repo-url> && cd cursor-flasher
uv sync
```

## Usage

```bash
# Verify accessibility permissions work from your terminal
uv run cursor-flasher check

# Start the daemon (backgrounds automatically)
uv run cursor-flasher start

# Start in foreground (useful for debugging)
uv run cursor-flasher start --foreground

# Check if the daemon is running
uv run cursor-flasher status

# Stop the daemon
uv run cursor-flasher stop
```

## How It Works

1. Polls Cursor's macOS accessibility tree every 500ms
2. Detects agent state by looking for specific UI elements (Stop/Accept/Reject buttons)
3. When the agent finishes and is waiting for input, shows a pulsing amber border around **only the window(s) that need attention**
4. Plays a system sound (default: "Glass")
5. Dismisses automatically when the agent starts working again, or after a timeout

## Configuration

Create `~/.cursor-flasher/config.yaml` to customize:

```yaml
pulse:
  color: "#FF9500"    # Border color (hex)
  width: 4            # Border thickness (px)
  speed: 1.5          # Pulse cycle duration (seconds)
  opacity_min: 0.3    # Minimum pulse opacity
  opacity_max: 1.0    # Maximum pulse opacity

sound:
  enabled: true       # Play sound on trigger
  name: "Glass"       # macOS system sound name
  volume: 0.5         # Volume (0.0 - 1.0)

detection:
  poll_interval: 0.5  # Seconds between accessibility tree polls
  cooldown: 3.0       # Seconds before re-triggering after dismissal

timeout:
  auto_dismiss: 300   # Auto-hide overlay after N seconds
```

All values are optional — defaults are used for anything not specified.

## Troubleshooting

### "Cannot read accessibility tree" / no detection

This is almost always an Accessibility permission issue. Run:

```bash
uv run cursor-flasher check
```

If it reports a failure, your terminal app needs Accessibility permission:

1. Open **System Settings → Privacy & Security → Accessibility**
2. Click the **+** button and add your terminal app (Terminal.app, Ghostty, iTerm2, etc.)
3. Restart the terminal after granting permission

### Cursor not detected

Make sure Cursor is running. The daemon identifies it by bundle ID (`com.todesktop.230313mzl4w4u92`).

### Overlay appears on wrong windows

Detection is per-window — only windows with active approval prompts (Accept, Reject, Run, etc.) should flash. If you see false positives, the detection patterns may need tuning for your Cursor version. Use `scripts/dump_a11y_tree.py` to inspect what the accessibility tree looks like.

## Development

```bash
# Run tests
uv run pytest tests/ -v

# Dump Cursor's accessibility tree (for debugging detection)
uv run python scripts/dump_a11y_tree.py --depth 8

# Manual overlay test (flashes all windows for 10 seconds)
uv run python scripts/test_overlay.py

# Manual overlay test (only windows needing attention)
uv run python scripts/test_overlay.py --per-window
```