What
Claude Code tracks where a session or turn originated from, and internally groups these into broader categories for reporting purposes. Several origin types have been added to the mapping that produces this grouping:
side-session-briefside-session-startside-session-wakeother
Each of these now explicitly maps to the host_synthetic category, rather than falling into it through a default catch-all case.
Why
This is an internal bookkeeping change. Making the mapping explicit rather than relying on a default case reduces the chance that new origin types get miscategorized in the future, but it should not change anything a user of Claude Code sees or interacts with directly.
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 side-session-brief, side-session-start, or side-session-wake correspond to in user-visible terms, only that…