You'll noticeTier: how much it should matter to you
3Useful: my rating, 1 to 5
3Signal: worth watching, 1 to 5
Prompt CacheArea: what it touches
ImprovementsKind: in v2.1.288,
ImprovementsSection of the release
What
The prompt cache lets the API reuse earlier parts of a conversation so replies come back faster and cost less. Claude Code can keep that cache warm by touching it on a timer. A resumed session is an earlier conversation you have reopened.
New code keeps the 1-hour prompt cache warm for resumed sessions by touching it on a timer.
It applies only to subscribers with a 1-hour cache lifetime, and only when server config sets resumeTouches.
Without resumeTouches, the keepalive stops for resumed sessions with the reason resume_touches_off. Before, there was no special check for resumed sessions.
Why
When it is enabled, a resumed conversation is less likely to lose its cache, which could mean fewer cache misses after you come back to it. When it is not enabled, resumed sessions do not keep the cache warm this way.
