You'll notice
New message tells you when the app driving your session, like Claude Desktop, didn't respond at startup or mid-turn
What
A new helper produces a user-facing message when the application driving a Claude Code session (such as Claude Desktop, or generically "the app driving this session") fails to respond. It distinguishes between two cases: failing to respond during SessionStart (when a session begins or resumes) versus failing to respond partway through a turn.
Why
Instead of silently continuing or failing unclearly, Claude Code now tells you explicitly when the driving app didn't respond and that it carried on without it, making it easier to understand why something might behave unexpectedly.