Hi bro, i think there is not best format. For me as a beginner, I use flowise with a vector memory because the AI task card of botpress is not as well advanced (for my own experience, maybe i am wrong). But when you use like Flowise or Stack AI (but it cost a lot lol I prefer flowise for free method), you can have a better experience on AI things. I will suggest you to build your own brain on StackAI for the beginning. After for the format it doesnt matter when you have a vector db or vector memory because your files are after in vectors.