Usage & Features

Library Health

On this page

Library Health tracks which skills your agents actually load and surfaces safe cleanup recommendations — similar to a storage scan that highlights files you rarely use.

What it tracks

  • Skill reads via Cursor postToolUse hooks when agents open SKILL.md files
  • chain capture events (secondary signal, deduped)
  • Manual test events via chain skill-usage touch <slug>

All data stays local in brain.db under your hub folder. Nothing is sent to the network.

Enable tracking hooks

Automatic (recommended): chain setup merges active-project and Library Health hooks into ~/.cursor/hooks.json when Cursor is detected. You can also run:

chain skill-usage install-hooks

Or use Skills → Library Health → Install Cursor hooks in the hub.

Manual: merge entries from core/hooks/cursor-hooks.example.json into ~/.cursor/hooks.json (user-global) or a project .cursor/hooks.json.

Hub views

  • Dashboard → Library Health — summary card with dormant count and reclaimable size
  • Skills → Library Health (#skills/insights) — full list, filters, and batch Deactivate (reversible)

Recommendations stay review-first. Core skills are never suggested for removal. Batch deactivate requires explicit confirmation and supports at most 20 skills per action.

CLI

chain skill-usage status
chain skill-usage touch commit

Disable tracking in Hub Settings (skillLibrary.trackingEnabled in hub-settings.json) if you prefer not to record invocations. See Advanced settings for other hub preference blocks.