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OSC 633;E set commandline
ESC ] 633 ; E ; commandline ; nonce BELOSC 633;E reports the explicit command line text along with a verification nonce. The format is OSC 633 ; E ; commandline ; nonce BEL. The nonce is a per-session secret known only to the shell integration script and VS Code, preventing replay attacks where malicious output could spoof a command.
This is unique to OSC 633 — OSC 133 has no equivalent. It exists because VS Code's run-recent-command and command-line history features need to know exactly what the user typed, not what the terminal can infer from cell contents (which loses information about quoting, escapes, and multi-line input). The nonce makes the protocol safe to use even when running untrusted commands that might emit arbitrary escape sequences.
How this is testedpartial
Send
Send
OSC 633 ; E ; ls -la ; nonce123 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
| Terminal | Version | Support | Notes |
|---|---|---|---|
| iTerm2 | 3.6.9 | ✓ yes | |
| Ghostty | 1.3.1 | ✓ yes | |
| Terminal.app | 2.15 | ✓ yes | |
| Kitty | 0.46.2 | ✓ yes | |
| VS Code | 1.113.0 | ? unknown | |
| Warp | 0.2026.03.18.08.24.03 | ? unknown | |
| Cursor | 2.6.21 | ? unknown |