Claude Code plugin hooks defined in hooks.json that reference ${CLAUDE_PLUGIN_ROOT} silently fail because the variable is not expanded by the harness and not set in the shell environment when the hook command is invoked. Tracking issue: anthropics/claude-code#42564.
Verified affected plugins as of 2026-04-28:
openai-codex/codex@1.0.2—SessionStart,SessionEnd,Stophooks all brokenclaude-code-plugins/ralph-wiggum— plugin author shipped hardcoded paths to work around itclaude-plugins-official/ralph-loop— same