Spell it out for me. The speaker wants it said in full, with nothing left to guess.
I’m not a mind reader. The speaker refuses responsibility for what was never said.
Don’t assume. It is often followed by the joke When you assume, you make an ass out of u and me.
Let me be clear. Just to be clear. The speaker restates the point so that nobody leaves with a different version.
Put it on the calendar. An agreement to meet becomes real when it has a time slot.
Over-communicate. Managers use this word as advice, not as a warning.