Appearance
Desktop Notifications (OSC 9/777)
Desktop notifications allow terminal applications to trigger system notifications. Two competing escape sequences exist: OSC 9 (iTerm2/ConEmu) sends a simple notification string, while OSC 777 (rxvt-unicode) supports structured notifications with title and body. Neither is standardized — support varies widely across terminals.
Common use case: long-running commands that notify when complete. Shells like zsh have plugins that automatically send a notification when a command takes longer than N seconds. The BEL character (0x07) is a simpler alternative — most terminals can be configured to show a visual bell or system notification on BEL.
How this is tested: Send
OSC 9 ; message BEL and verify the terminal accepts the notification sequence.Analysis2026-03-26
Supported by 7 of 8 terminals (88%). Not supported by: Cursor. Part of the Rich TUI baseline.
Supported by 10 of 13 backends (77%)
Terminal Applications
| Terminal | Version | Support | Notes |
|---|---|---|---|
| iTerm2 | 3.6.9 | ✓ yes | |
| Ghostty | 1.3.1 | ✓ yes | |
| VS Code | 1.112.0 | ✓ yes | |
| Warp | 0.2026.03.18.08.24.03 | ✓ yes | |
| Cursor | 2.6.21 | ✓ yes | |
| tmux | 3.6a | ✓ yes | |
| Kitty | 0.46.2 | ✓ yes | OSC 9 notifications not exposed via Python batch bridge |
| Terminal.app | 2.15 | ✓ yes | |
| GNU Screen | 5.0.1 | ✓ yes |
Headless Backends
Parser correctness only — a ✓ means the parser accepts the sequence.
| Backend | Version | Support | Notes |
|---|---|---|---|
| vterm | 0.2.0 | ✓ yes | |
| Alacritty | 0.26.0 | ~ partial | OSC 9 notifications not exposed via alacritty_terminal API |
| WezTerm | 0.1.0-fork.5 | ~ partial | OSC 9 notifications not exposed via wezterm-term API |
| vt100 | 0.2.1 | ✗ no | Not implemented — pure TypeScript emulator |