[BUG] /ultraplan not available on WSL despite meeting all requirements

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?

/ultraplan command is unavailable on WSL2 (Ubuntu). The command does not appear in the slash command list, and typing /ultraplan returns "Unknown skill: ultraplan". The same account on Windows native Claude Code v2.1.92 works correctly.

What Should Happen?

/ultraplan should be available on WSL2. Documentation lists only two requirements: Claude Code on the web account and a GitHub repository. WSL is not mentioned as an unsupported environment.

Error Messages/Logs

Unknown skill: ultraplan
Args from unknown skill: test

claude remote-control
Error: Remote Control is not yet enabled for your account.

Steps to Reproduce

1. Install Claude Code on WSL2 (Ubuntu) via curl -fsSL https://claude.ai/install.sh | bash
2. Run claude auth login and authenticate with Claude Max account
3. Open claude in any directory
4. Type /ultraplan
5. Result: "Unknown skill: ultraplan"

Note: Same account on Windows native Claude Code shows /ultraplan correctly.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

v2.1.92 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

WSL (Windows Subsystem for Linux)

Additional Information

This issue affects WSL2 (Ubuntu) specifically. The same Claude Max account works correctly on Windows native Claude Code v2.1.92.

Claude in Chrome also explicitly states "not supported in WSL at this time" but ultraplan documentation has no such disclaimer.

Remote Control also fails with: "Error: Remote Control is not yet enabled for your account" on WSL, but works on Windows native.

Please either add WSL support or document the WSL limitation clearly in the ultraplan documentation.