Function brief_text 

pub(crate) fn brief_text(pair: &str, brief: &HandoffBrief) -> String

The brief as the successor receives it.

Which half is authoritative is stated first. PART 1 is read off the transcript, git and the board, so it is the half the successor trusts for facts; PART 2 is its predecessor’s own account, written in whatever shape that session chose.