Ask HN: Did you add an AI character to your product? How did it go?

I see many apps who have been adding open-ended conversations with AI characters to their products, e.g. a calendar app where you can discuss your day, a fitness coaching app where you discuss your goals and progress.

In theory, it could increase engagement and offer such an interactive experience but it can get pretty unwieldy to offer such an open-ended experience.

Have you tried doing that? Was it helpful at all? How did you approach re-designing the product experience? Any unexpected benefits/risks?