A written agreement should remain understandable after everyone forgets the conversation around it.

Documents get written by people who still remember the discussion, and read by people who do not. Everything that was obvious in the room, what was meant by soon, which of the two rooms, who the it referred to, disappears within months, leaving a text that seems clear to its authors and ambiguous to everyone else, including their future selves. Writing for a stranger is the only reliable test. Shared memory is not a clause.

Read your next agreement as though you knew nothing about the situation. Add the detail you were relying on remembering, even where it feels obvious now.