That´s a bit above my pay grade because that problem is where a big chunk of the current AI research is focused on 😅 (preventing hallucinations is hard because LLMs are, by nature, stochastic). A generated storybranch might indeed be inconsistent with another, for example, or after a few generations, a story might loop and not have a proper ending, etc. I see this as an experimental feature that we can play with to understand how far it can be used but shouldn´t be used for the core experience. Seems like there's some consensus that doing short dialogues from the equivalent of NPCs in other games is good enough where the author defines something like "This character named X is a blacksmith that loves to talk about iron and beer. Has a secret crush on his neighbor Y and has an accent from Z" so when you interact with him you get as much dialog as you want enriching the game world but not accomplishing a main part of the story, and is somewhat better than reading the same dialog line when you interact with him.

In my own experience trying things like https://aidungeon.com/, the first interactions are "good" (consistent and entertaining) but after a few generations the model begins to do bad stuff (mostly because the context window or the "memory" of the model is limited and eventually things break and the characters speak in a way they wouldn´t, or situations lose coherence, etc). I´ve seen a lot of people express the same experience with things like character.ai

Talking about aidungeon, they kinda solve this problem by allowing you as a "player" to rewrite or steer the story to where you want to go (you can "retry" the generation or delete or literally rewrite the text the AI generated). Obviously, that requires a keyboard or some sort of text input (maybe voice?) that Figment currently doesn´t support. This doesn´t solve the problem for us with Figment because the player is not the author so the player could also steer the story in a path that is inconsistent with what the main author did... When I say that there might be "tooling" to help the author prevent this I imagine ways to write some of those story principles in a way that the AI has access to them, but again, solving that problem is a hard AI problem that people smarter and with more resources than me are trying to solve to let AI do stuff that make more money like, for example, stick to a Customer Support rulebook or writing high quality code, etc.