REST, similarly so many wonderful technological buzzronyms before it, was something specific that has come to mean something vaguely “not SOAP.” Because of this, nap triesto pick safe, undestructive defaults. The tradeoff with this decision is there is a little bit more customization required to make things work than a more traditional modeling backend (such as a relational database). To facilitate this, nap has an extensive list of options to make setting these configuration easy as possible.
Your nap models will only go as far as your API allows. For instance, if your API’s collections only return partial data about your object, you won’t have access to the left out fields (and risk saving over them without proper configuration!). The more you expose in your API the easier using nap will be.