[BUG] Project plugin using older cache version after update

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?

When I update a plugin on our company's internal plugin marketplace and bump the version number, and then update the marketplace in Claude Code, it downloads the new plugin version in the cache, but does not update the version used by the project (continues to use the previous version). I have tried /reload-plugins and exiting and restarting Claude Code but this does not update the version. If I go to /plugin and select Update on the plugin it reports that I am already updated to the latest version and shows the correct version number, but the plugin view in Claude Code still shows the old version number.

It's not just a version display problem, when I go to run the plugin it does not include the updated functionality e.g. if I have added a new skill to the plugin, that skill is not included.

What Should Happen?

The plugin should update to the latest version available in the marketplace, and the version number in the /plugin view should display the latest version.

Error Messages/Logs

Steps to Reproduce

1. Add a new skill to plugin. Commit and push changes to the repo (version number auto-bumps to 0.1.35).
2. Run Claude Code in a project. Go to /plugin -> Marketplaces, select the marketplace repo and select Update.
3. Update is apparently successful (message: "Updated 1 marketplace (1 plugin bumped)".
4. Go to Installed (plugins) view, select plugin, version number shows previous version 0.1.34.
5. Select "Update now" on the plugin.
6. Message displayed: "{plugin-name} is already at the latest version (0.1.35)"
7. Exit and restart Claude Code
8. Go to /plugin and select plugin, version number is still 0.1.34
9. Open ~/.claude/plugins/installed_plugins.json. Entry for plugin with scope "project" shows version 0.1.35 and install path includes 0.1.35.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

Stopped working around 2-3 days ago

Claude Code Version

2.1.84

Platform

Other

Operating System

Ubuntu/Debian Linux

Terminal/Shell

VS Code integrated terminal

Additional Information

_No response_