[BUG] Custom skills are not recognized on Claude Code on the web

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?

Custom skills are not recognized on Claude Code on the web. When a custom skill is invoked, it is not recognized and does not execute.

What Should Happen?

Custom skills should be recognized and executed when invoked on Claude Code on the web.

Error Messages/Logs

N/A

Steps to Reproduce

1. Open Claude Code on the web
2. Invoke a custom skill
3. The skill is not recognized and does not execute

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.107 (Claude Code)

Platform

Anthropic API

Operating System

Other Linux

Terminal/Shell

Non-interactive/CI environment

Additional Information

_No response_