Ghost plugin 'marketplace-plugin' shown in /plugin UI but cannot be uninstalled

Bug Description

A plugin called marketplace-plugin appears in the /plugin menu UI with status unknown · ✘ failed to load · 1 error, but it cannot be uninstalled via the CLI and does not exist in any configuration file.

Steps to Reproduce

1. Open Claude Code and run /plugin to view installed plugins
2. Observe marketplace-plugin Plugin · unknown · ✘ failed to load · 1 error in the list
3. Run claude plugin uninstall marketplace-plugin

Expected Behavior

Either the plugin uninstalls successfully, or it doesn't appear in the UI if it's not tracked anywhere.

Actual Behavior

✘ Failed to uninstall plugin "marketplace-plugin": Plugin "marketplace-plugin" not found in installed plugins

The plugin is not present in any of the following files:

• ~/.claude/settings.json (enabledPlugins key)
• ~/.claude/plugins/installed_plugins.json
• ~/.claude.json
• Any project-level .claude/settings.json or .claude/settings.local.json
• Any marketplace manifest under ~/.claude/plugins/marketplaces/

Debug Log

Plugin not available for MCP: marketplace-plugin - error type: generic-error

(repeated multiple times across sessions)

Environment

• Claude Code version: 2.1.50
• OS: macOS Darwin 25.3.0
• Shell: zsh