A board is not a history archive
Long-running work needs a live operational board: what is true now, what must not be forgotten, what is next, and how to update the board. It should not become a museum of every old plan. The cwkPippa NEW-SESSION-REMINDER.md file is exactly this pattern: a single living document overwritten between sessions, holding the freshest operational truth.
The board survives compaction and model replacement
A good board lets the next instance — same model after compaction, or a different model entirely — inherit the current object state instead of replaying a novel-length transcript. The transcript may not even be available; the board must stand alone.
Keep it small and sharp
Put detailed narratives in history. Put live invariants on the board. If the board is too long to read at session start, it has failed its own purpose. A 200-line board nobody reads is worse than a 20-line board everyone trusts.