[BUG] Cowork: personal GitHub marketplace never updates — clone silently fails, runtime serves stale version despite correct metadata

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?

Summary

Updating a personal GitHub-sourced plugin in Cowork is impossible through the UI. After pushing a new version, Cowork keeps running the old one. Its install metadata is written as if the update succeeded, but no files are ever placed on disk, and the runtime continues loading the previous version even after the recorded install path is manually populated.

Suspected cause

The in-sandbox clone appears to fail silently (possibly SSH vs HTTPS, see #26588), so files are never written, while metadata is recorded optimistically. Separately, runtime does not load from the recorded installPath, pointing at a second uncleared copy/state.

Workaround

Disable the marketplace plugin; install the plugin locally/manually from .plugin file instead.

Related

#26588, #38185, #40600

What Should Happen?

Expected

Cowork re-clones at the latest commit and runs v0.2.2.

Error Messages/Logs

Steps to Reproduce

Repro

1. Add a personal marketplace from a public GitHub repo (Customize → Plugins → Personal → Add from repository). Install a plugin (v0.1.0).
2. Push a new version (v0.2.2) to the default branch — bump version in <plugin>/.claude-plugin/plugin.json.
3. Restart Claude Desktop. Plugin still runs/show v0.1.0.
4. Remove and re-add the marketplace via the UI; reinstall the plugin.

Actual

• ~/.claude/cowork_plugins/marketplaces/<mp>/ and ~/.claude/cowork_plugins/cache/<mp>/ are empty after install — no clone/cache files are written.
• installed_plugins.json nonetheless records the install as succeeded: correct version (0.2.2), correct gitCommitSha, and an installPath under cache/<mp>/<plugin>/0.2.2 that does not exist on disk.
• Customize UI shows the old version (0.1.0) with a "last updated" timestamp predating the reinstall.
• Manually git clone-ing the repo over HTTPS works instantly, and copying the plugin files into the exact installPath from installed_plugins.json still does not change runtime — a fresh Cowork task still loads the old SKILL.md (0.1.0).
• Disabling the marketplace plugin and doing a manual/local install of 0.2.2 runs correctly → confirms the marketplace path specifically is broken.

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.183

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Environment

• Claude Desktop (Cowork) — version: Claude 1.14271.0 (c8f4d8) 2026-06-18T05:47:57.000Z
• macOS 15.7.3 (24G419)
• Date: 2026-06-20
• Marketplace source: public GitHub repo (github source), plugin installed at user scope