Novel / world builder assistant

Ihave tried several chat bots that are advertised as writing assistants. However they all lack 1 key feature that i deem absolutely necessary. None of them create a local data store to save what i discuss with the ai so that future chats retain the integrity of the data. For example, i talk to the ai and genetate a list of characters for the book. Then a few hours later i want to go back and make some changes, or just review some things, and the chatbot has forgotten or confused the data. For this to be a real tool, and not just a gimmick, the ai needs to be sure to keep things we talk about in a permanent storage, preferably on my device or in a cloud space i control. Otherwise, after an hour or so, the ai has lost all the information that we used to create the world. To this end there needs to be a way to flag important information to be saved in a way the ai can readily go back and refresh itself to maintain the integrity of this data.