/checkpoint — Structured Session Handoff

Produce a state snapshot that the next session (yours, or a collaborator's, or a fresh-context reboot) can resume from in under a minute. The narrative quality_reports/session_logs/ continues to live separately — /checkpoint writes the structured side: facts, file pointers, and next-actions.

When to use

• Before a long break, model switch (Opus ↔ Sonnet ↔ Haiku), or end of a working day.
• Before auto-compaction would otherwise discard mid-plan context (paired with the PreCompact hook).
• Before handing off to a collaborator on the same repo.
• After completing a chunk of a multi-session plan, when "where am I" is the first question the next session will ask.

When NOT to use