It's the obvious question, and the honest answer has a caveat. ZChat includes a chatbot with knowledge-base grounding and handoff - but it ships as an API you integrate. The stock widget connects visitors to human agents and falls back to the message form when nobody is on. Putting an AI into that gap is work you'd wire up, not a switch you flip.
Worth weighing before you do: overnight is when questions are least likely to be routine and a wrong answer sits unchallenged for eight hours. Some teams genuinely want AI there; others find that capturing the message well and replying first thing beats a bot guessing at 3am. We wrote up when not to use a chatbot for exactly this decision.