Plugin marketplace: shallow clone + SSH remote causes missing plugin files

Bug Description

When installing plugins via /plugin from the claude-plugins-official marketplace, some plugins show in the "Discover" panel but fail to install with:

Error: Failed to install: Source path does not exist: ~/.claude/plugins/marketplaces/claude-plugins-official/plugins/<plugin-name>

Root Cause

The marketplace repo is cloned as a shallow clone (depth=1) with an SSH remote (git@github.com:...). This causes two compounding issues:

1. SSH key mismatch: If the user's SSH key is not at the default path git expects, git fetch fails silently. The /plugin marketplace update command reports success but no files are actually pulled.

1. Incomplete working tree: The shallow clone only materializes a subset of plugin directories to disk. In testing, git ls-tree HEAD plugins/ showed 29 plugins tracked by git, but only 14 were checked out to the working tree. The other 15 (including plugin-dev, ralph-loop, LSP plugins, etc.) were missing from disk.

Steps to Reproduce

1. Have an SSH configuration where the default key path doesn't match what git expects
2. Use /plugin → Discover → try to install a plugin like plugin-dev
3. Observe the "Source path does not exist" error
4. Running /plugin marketplace update reports success but doesn't fix it

Workaround

cd ~/.claude/plugins/marketplaces/claude-plugins-official

# Fix 1: Switch to HTTPS so gh auth is used instead of SSH
git remote set-url origin https://github.com/anthropics/claude-plugins-official.git

# Fix 2: Unshallow and restore all files
git fetch --unshallow origin main
git checkout HEAD -- plugins/

Suggested Fix

• Clone marketplace repos via HTTPS instead of SSH (or respect the user's SSH config)
• After clone/update, verify the working tree matches the git index
• Consider a full clone instead of shallow, or at minimum ensure all tracked files are checked out

Environment

• macOS (Darwin)
• Claude Code CLI (latest as of 2026-02-26)