[BUG] /terminal-setup incorrectly rejects Windows Terminal

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

The /terminal-setup command fails to run in Windows Terminal despite the error message listing Windows Terminal as a supported terminal. The error message is contradictory - it says "cannot be run from windows-terminal" but then lists "Windows Terminal" under supported terminals.

The WT_SESSION and WT_PROFILE_ID environment variables confirm that the session is running inside Windows Terminal, so the detection logic appears to correctly identify Windows Terminal but then incorrectly rejects it.

What Should Happen?

The command should configure the Shift+Enter shortcut for Windows Terminal since it is listed as a supported terminal in the error message itself.

Error Messages/Logs

Terminal setup cannot be run from windows-terminal.

This command configures a convenient Shift+Enter shortcut for multi-line prompts.
Note: You can already use backslash (\) + return to add newlines.

To set up the shortcut (optional):
1. Exit tmux/screen temporarily
2. Run /terminal-setup directly in one of these terminals:
   • Windows: Windows Terminal
   • IDE: VSCode, Cursor, Windsurf, Zed
   • Other: Alacritty
3. Return to tmux/screen - settings will persist

Steps to Reproduce

1. Open Windows Terminal on Windows 11
2. Launch Claude Code from either Git Bash (MSYS2) or PowerShell 5.1
3. Run /terminal-setup
4. Error appears stating it cannot be run from windows-terminal

Environment variables present:

TERM=xterm-256color
SHELL=/bin/bash.exe (Git Bash) or PowerShell 5.1

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

v2.1.81

Platform

Other

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_