Claude Code just added idle compaction, and this could save a LOT of usage.

Imagine you have a session with 500K tokens of context. You come back 90 minutes later, your prompt cache has expired, and Claude has to process all 500K tokens again without the cache. That’s insanely expensive.

Now, Claude automatically compacts idle sessions before the cache expires. Instead of reprocessing 500K tokens, you might only need to process, say, 100K.

And imagine the difference with an 800K-token session.

I always recommend manually compacting after finishing parts of a task, but most people never do it.

This feature could save the average Claude Code user a ton of usage.