Notes
A chat is a transcript: it scrolls, and the thing you keep re-stating gets buried. A note is the opposite — a document that sits beside the conversation, is edited in place, and is read into the model’s context on every turn.
A note pinned to a node is visible to that node and every branch below it — the same direction context already flows, but live rather than frozen. Pin the spec to the root once and every branch you open under it starts already knowing it; edit the spec and they all see the new one on the next turn.
Reach for a note when you have standing reference that belongs to a part of the tree: a schema, an API contract, a brief, decisions already made. Open them from the Notes button in the chat header.