Hey, thanks for the detailed analysis. The comparison between Agent Chat and Agents View is a really useful data point.
This is a confirmed bug that affects sessionStart hook additional_context injection.
This was also reported in this thread, where our team confirmed the root cause and has filed an internal bug. No ETA on a fix yet, but the timing angle from your report (showing it’s worse in one view than the other) will help scope the fix.
Unfortunately, there’s no workaround right now. The env field from the same hook works because it goes through a separate storage path, but it doesn’t cover the additional_context use case. If any of your injected content is fairly static, duplicating it into a .cursor/rules file is a partial fallback, though I know that doesn’t cover your dynamic CLI reference setup.
I’ll update this thread when the fix ships.