kMessageCapDefaultMargin top-level constant

int const kMessageCapDefaultMargin

The default margin between the live message count and the learned cap at which the pre-emptive compaction trigger fires (open question 1 on the card: cap − margin). 16 messages ≈ several turns of tool-call + result growth at the observed ~7 calls/min — big enough that a burst of turns between the trigger and the request cannot re-wedge the run, small enough not to compact wastefully early.

Implementation

const int kMessageCapDefaultMargin = 16;