Hi, one thing I am really struggling with in AI studio API is stop_sequences. I know how to request them, but cannot see how to determine which stop_sequence was triggered. They don't show up in the stop_reason like most other APIs. Is that something which vertex API can do? I've built some automation tools around stop_sequences, using them for control logic, but I can't use Gemini as the controller without a lot of brittle parsing logic.