Yeah once you start working at the feature level, you’re into product design, and that’s an entirely different realm of working that, IMO, shouldn’t even involve code. Even higher-level software design —e.g. broad stroke architecture like figuring out your data model and how it will be accessed— is better off being done before any significant amount of code gets written. Claude, et al will happily walk you straight off a cliff if you ask it to, and not having that stuff sketched out ahead of time is a most efficient way of accidentally doing that.