Compaction wont save you, in fact calling compaction will eat about 3-5x the cold cache cost in usage ive found.

Wouldn't it help if the system did compaction before the eviction happens? But the problem is that Claude probably don't want to automatically compact all sessions that have been left idle for one hour (and very likely abandoned already), that would probably introduce even more additional costs.

Maybe the UI could do that for sessions that the user hasn't left yet, when the deadline comes near.