cowork skils bug

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?

Bug-Report-Skills-Not-Loading.md

Bug Report: User-Created Skills Not Loading in Cowork Mode

Summary

36 user-created skills are registered in the .skills/manifest.json with valid skillId entries and "enabled": true, but none appear in the runtime available skills list, the Settings > Capabilities UI, or are invocable by name in any session. Only plugin skills (finance, legal, sales, productivity) and built-in skills load. The upload endpoint also returns HTTP 500 when attempting to add new skills through the UI.

Environment

• Platform: Windows
• App Version: Claude Desktop (Cowork mode)
• Plan: Paid (Pro/Team)
• Number of affected skills: 36 user-created skills
• Date first noticed: February 16, 2026

Steps to Reproduce

1. Open Claude Desktop in Cowork mode with a mounted workspace folder
2. Go to Settings > Capabilities > Skills
3. Observe "No skills yet. Add a skill to get started." despite 36 registered skills
4. Attempt to invoke any user-created skill by name (e.g., "run cb-monday-audit") — skill is not found
5. Attempt to upload a new .skill file via the "Add a skill" button — returns "Internal server error"

Expected Behavior

• All 36 skills in manifest.json should appear in Settings > Capabilities
• All skills should be invocable by name in any session
• The upload endpoint should accept valid .skill files

Actual Behavior

1. Settings > Capabilities shows "No skills yet" — despite 36 skills in manifest
2. Runtime skill list omits all user-created skills — only plugin skills and built-ins appear
3. Skills not invocable by name — requesting "run cb-monday-audit" returns skill not found
4. Upload endpoint returns 500 — attempting to add a new .skill file fails with Internal Server Error
5. .skills/skills/ directory intermittently empty — directory contents disappear mid-session (mount instability), though they were present at session start

Manifest Evidence

The manifest.json contains all 36 skills with valid entries, for example:

{
  "skillId": "skill_01K6hdnxciQch9Nv3nhcRy6E",
  "name": "cb-ltc-activity-codes",
  "description": "LTC activity codes audit...",
  "creatorType": "user",
  "updatedAt": "2026-02-16T12:27:22.924266Z",
  "enabled": true
}

All 36 entries follow this pattern with unique skillIds, "creatorType": "user", and "enabled": true.

Session Evidence

• At session start: ls .skills/skills/ showed 10 skill folders on disk
• Mid-session: same directory returned empty (only . and ..)
• Manifest was readable early in session, then FileNotFoundError later
• Plugin skills (finance, legal, sales, etc.) load and function normally throughout

Possibly Related Issues

• #24859 — Cowork Windows path resolution bug for plugin skills (wrong directory traversal)
• #14733 — User-provided skills not appearing in /skills command output
• #25548 — Claude agent unable to discover skills in .claude/skills/ directory
• #9716 — Claude Code skills not recognised in .claude/skills/

Impact

This is a complete failure of the user skills system in Cowork mode on Windows. No user-created skills can be discovered, loaded, or executed through the normal skill invocation pathway. The only workaround is manually reading SKILL.md files from disk during a conversation — which also fails when the mount becomes unstable mid-session.

The user has invested significant time building 36 custom operations skills for daily business use. The skills pipeline regression makes the entire custom skills feature non-functional.

Workaround

None reliable. Reading SKILL.md files directly from .skills/skills/ works only when the directory mount is stable, which is intermittent.

What Should Happen?

see pasted text

Error Messages/Logs

see pasted text

Steps to Reproduce

see pasted text

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

latest

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_