The agreement that preserves friendship is usually the one neither person has to guess about.

Vagueness between friends feels like generosity and works like a debt. Nobody wants to name a number or a date because naming it seems cold, so both people carry a private version of the arrangement, and the versions differ. The awkward five minutes at the start is what buys the ease afterward.

When money, time or a shared thing is involved, say the amount and the date out loud and let it be slightly awkward. Write it in a message so neither of you has to rely on memory. Then stop managing it, which is the whole point of having agreed.