What
When saving part of a session transcript (the saved log of a conversation) fails, Claude Code now marks that record as "lost" before reporting the error as before.
Why
A failed save is now noted explicitly instead of only raising an error.
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubt
The finding does not say what reads the `"lost"` mark or what the reader sees because of it.