You'll notice
Useful2 Signal1
Prompt-cache diagnostics only build their payload when asked, so requests do less work.
What's wrong with this entry?
Anonymous. No account, no email.
What
The prompt-cache invalidation tracker now takes a callback for message hashes and the raw messages, and stores the request body behind a function instead of building it up front. Same recorded data, less work per request when no diagnosis is requested.
Evidence
getMessageHashes
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
Related
Other releases about the same thing. Found by shared names or similar wording; neither means one caused the other.