Skip to content

OSC 133;P properties

Category: extensions · Baseline: rich · Tags: Operating System Commands (OSC) · Specification ↗

ESC ] 133 ; P ; key=value BEL

OSC 133;P sets properties or metadata about the current command. The format is OSC 133 ; P ; key=value BEL, where common keys include Cwd (current working directory), CmdLine (the literal command text), and shell-specific state.

Property reporting lets the terminal track shell state without parsing command output or relying on environment variables. For example, the terminal can know the working directory of each command in scrollback, enabling features like "open this command's directory" or "reproduce this command in a new tab with the same cwd". VS Code's OSC 633 extends this concept with additional VS Code-specific properties.

How this is testedpartial
Send OSC 133 ; P ; Cwd=/tmp BEL and verify the terminal consumes the sequence (cursor doesn't advance, terminal remains responsive).

The same probe runs against headless backends (via Termless) and real terminal apps (via a daemon launched in each terminal). This lets us distinguish parser correctness from rendering correctness.

Analysis2026-04-06

Supported by all 9 tested terminals — universal adoption. Part of the Rich TUI baseline.

Supported by 11 of 14 backends (79%)

Terminal Applications

TerminalVersionSupportNotes
iTerm23.6.9✓ yes
Ghostty1.3.1✓ yes
Terminal.app2.15✓ yes
Kitty0.46.2✓ yes
VS Code1.113.0? unknown
Warp0.2026.03.18.08.24.03? unknown
Cursor2.6.21? unknown

Headless Backends

Parser correctness only — a means the parser accepts the sequence.

BackendVersionSupportNotes
Alacritty0.26.0✓ yes
vt100.js0.2.1✓ yes
vterm0.2.0✓ yes
WezTerm0.1.0-fork.5✓ yes
xterm.js5.5.0✓ yes