A widely expected account management feature, the thread history is not only convenient but even more relevant for AI workflows.
Being that AI has a such a multifaceted skill set, our use of it will also broaden Users will benefit from a clear thread history as they switch between various topics.
Skewed toward more frequent or advanced users, this pattern requires a user to have enough usage to warrant the using the thread history feature.
However, if not tucked away an easily accessible history can allow novice users to understand a single focus per thread is optimal & that you cn return to expand on a thread at any time.
Thread histories can be segmented easily if a "new thread" button is provided but consider if some simple heuristics can help organise your users thoughts. Perhaps a threads history is separated on each new session to align with their natural return to the product.
Another key consideration is how long the history is maintained, when providing this to free users, a large amount of data can quickly accumulate. Set a limit on it's storage & leverage it as paid account feature.