Scene beat
A one-line instruction describing what a scene needs to accomplish, written before the prose exists.
A scene beat is the smallest unit of intent in a draft: "Mara finds the letter and decides not to open it." It is not a summary of what you wrote — it is a note to your future self about what still needs writing.
Beats matter more in AI-assisted drafting than they did on paper. A generation started from a blank cursor produces plausible prose about nothing in particular; a generation started from a beat produces prose that moves the story. The beat is the difference between the model guessing and the model executing.
Scene beat in NovelKnow
Every scene carries a scene beat field. It is stored on the scene, so you can restructure a chapter by moving beats around before a single line of prose exists — and generation reads it together with the codex entries the scene mentions.