This is for tracking projects that span multiple Claude conversations over days or weeks. It creates persistent project files in your user data directory to maintain task lists, decisions, blockers, and links to relevant conversations. The idea is you mention a project name and it auto-updates the state file, generates status reports, and reminds you about follow-ups. Honest take: the value depends entirely on whether you actually work on the same project across multiple conversations. If you do, having a single source of truth that survives conversation boundaries could be genuinely useful. If most of your work fits in one session, you probably don't need this.
npx skills add https://github.com/onewave-ai/claude-skills --skill cross-conversation-project-manager