UX design has the concept of personas. They act like unit tests, an insurance policy against scope creep in the UX that serves no-one (or at least, not your cu

UX design has the concept of personas. They act like unit tests, an insurance policy against scope creep in the UX that serves no-one (or at least, not your customers) and in essence break the API goals. The key to personas is to create an idea of the end user, one persona per category of users. You may have power users, lay users, and non-developers. These personas should be quite concrete... give them a name, a face, and age, a story. Then, when you are building the UX hold up the proposal and ask "Did we do good by Tom, Sally and Robert?". If the answer is no to any, you may have a problem, and if it's no to all you definitely have a problem. Personas help ensure the UX keeps solving user problems. Making their life easier. I would think that as APIs are to help solves problems and make life easier, that personas could be used here too... to create a strong idea of the people that do use an API. So long as the personas are honest... and really reflect who your users will be, or are... then it should help you create the right documentation and API for them.