[BUG] Cowork slash commands return "Unknown skill" — affects custom org plugin skills AND built-in /feedback

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?

After renaming a skill folder in our org plugin from daily-brief to daily-brief-tungsten (repo: Tungsten-Automation-AI-Office/Claude-Plugins, plugin name: org-skills), Cowork's slash command resolver returns "Unknown command" for both my custom skill and Anthropic's /feedback. Both commands appear in the / autocomplete dropdown with their correct descriptions — but invocation fails immediately. Reproducible across ~50 Tungsten Automation users, persists across full app restarts, marketplace.json version bumps (1.0.0 → 1.0.2), and rename. Natural-language triggering of the same skills works correctly.

What Should Happen?

Typing /org-skills:daily-brief-tungsten should invoke the skill that the autocomplete dropdown advertises. Typing /feedback should open Anthropic's built-in feedback flow. The resolver should match what autocomplete shows.

Error Messages/Logs

Unknown command: /org-skills:daily-brief-tungsten
Unknown skill: feedback.

Steps to Reproduce

In an org plugin marketplace, rename a skill folder (e.g. daily-brief → daily-brief-tungsten)
Update SKILL.md frontmatter name: to match new folder
Bump marketplace.json version
Commit and push (auto-syncs to Cowork per our admin)
Restart Cowork fully (close from system tray, reopen)
Type / — autocomplete shows the renamed skill with correct description
Select it or type /org-skills:daily-brief-tungsten — observe "Unknown command"
Try /feedback — observe "Unknown skill: feedback."
Try natural language ("give me my daily brief") — works correctly

Claude Model

Opus

Is this a regression?

No, this never worked

Last Working Version

N/A — first time attempting a skill folder rename

Claude Code Version

Not applicable — I'm using Cowork desktop app, not Claude Code CLI. Cowork version: latest available (auto-updated).

Platform

Other

Operating System

Windows

Terminal/Shell

Other

Additional Information

Plugin: org-skills v1.0.2 in marketplace tungsten-automation-claude-plugins

Repo: github.com/Tungsten-Automation-AI-Office/Claude-Plugins

Affected users: ~50 Tungsten Automation employees

Workaround: natural-language triggering ("give me my daily brief")

The fact that Anthropic's own /feedback also returns "Unknown skill" suggests this isn't just a rename edge case — the entire skill registry resolver appears broken in affected Cowork instances