Under the hood
Session history recorder gains a pending state that holds messages until startup hooks finish
What
Claude Code's internal session-history tracker now has a "head hooks pending" state. When it's active, incoming messages are held instead of being recorded immediately, and are replayed once the hooks that run at the start of a session finish resolving. The underlying hook lifecycle machinery now publishes this pending state and waits until after the transcript is spliced in before releasing it, rather than releasing right away.
Why
This avoids recording conversation history out of order or before session-start hooks have had a chance to run, keeping the saved transcript consistent.