Terminal Bell Notifier

Zero-dependency OpenCode plugin that sends desktop notifications using OSC 9 terminal escape sequences.

No osascript, no notify-send, no external binaries, no npm dependencies. Just a single escape sequence written to stdout that your terminal emulator interprets as a notification.

Install

Add to your opencode.json:

{
  "plugin": ["opencode-terminal-bell-notifier@latest"]
}

Restart OpenCode.

What it does

Sends a terminal notification when:

• The agent finishes a task
• The agent asks a question
• Permission is requested
• An error occurs

How it works

The plugin writes an OSC 9 escape sequence directly to stdout:

\x1b]9;<message>\x07

Terminal emulators that support OSC 9 (Ghostty, iTerm2, kitty, foot, Windows Terminal, Warp) display this as a native desktop notification. Terminals without OSC 9 support still fire the trailing BEL byte (\x07) as an audible or visual bell.

How it differs from other notification plugins

Most notification plugins shell out to platform-specific tools (osascript on macOS, notify-send on Linux) or pull in npm packages like node-notifier. This plugin does none of that:

• No runtime dependencies
• No child processes
• No platform detection
• No permission prompts except native OS notifications permission
• Works on any OS as long as the terminal supports OSC 9 or BEL

The tradeoff is that notifications are handled entirely by the terminal emulator, so behavior (sound, badge, banner) depends on your terminal's settings.

If your terminal is in the foreground, it may or may not suppress the notification. Check your terminal's documentation for notification configuration options.

Terminal support

Terminal	OSC 9 notifications	BEL fallback
Ghostty	✅	✅
iTerm2	✅	✅
kitty	✅	✅
foot	✅	✅
Windows Terminal	✅	✅
WezTerm	✅	✅
Warp	✅	✅
Terminal.app	❌	✅
Alacritty	❌	⚠️ visual only
GNOME Terminal / VTE	❌	⚠️ audio only
Konsole	❌	✅
xfce4-terminal	❌	✅
urxvt	❌	✅
ConEmu	❌	✅
mintty	❌	✅
Tabby	❌	⚠️ buggy

License

MIT