My long ChatGPT threads quietly forget the beginning, so I keep decisions somewhere else

Been working on this backend migration for like two weeks and my chat with ChatGPT is one of those endless scrolls. Last Tuesday it confidently told me we'd 'decided' on the wrong database. We had literally decided the opposite on day one. The first fifty messages just... gone. No warning, no 'hey this chat is getting long', it just started acting like the beginning never happened. I tried the dumb stuff first. Copy-pasting summaries into a fresh chat every morning (lasted two days before the summaries got bloated and I quietly stopped updating them lol). Then that DECISIONS.md trick where you make the model keep a decisions file. It never updated the file. It just said it would, very convincingly, for three days straight. Honestly the thing that finally stuck is boring: I keep the important stuff (decisions, why we decided them, the stuff that would cost me a week if forgotten) in an external memory thing that all my AI tools read over MCP. I use Vilix AI for that part. When a chat's beginning rots away, I just ask about the decision and it's there, because it was never living inside that chat's context window in the first place. Annoying part is the models are lazy about saving. Half the time I have to literally say 'save that' or it just won't. And setup took me like 40 minutes because I fumbled the OAuth twice like an idiot. But once the decision is in there it's in there. My long chats can forget whatever they want now, it stopped mattering. submitted by /u/Asly97 [link] [comments]

Source: r/ChatGPT | 2026-09-18