What belongs in a handoff note so the next person does not repeat work?

Asks which handoff-note fields prevent duplicate checks, repeated messages, and restart cost.

For handoff notes, the field I miss most is “do not repeat.” Current state and next action are useful, but the next person also needs to know what was already checked, which option was ruled out, and who was already contacted. Otherwise they spend the first hour recreating the same path. What belongs in a handoff note so the next person can start without repeating work?