> Before launching an API, you should come up with 5-10 compelling usecases that someone couldn't use your website for.
Disagree. The most important thing by far is to have an API at all. Just being able to build your main site but with a different UI (or as a native program) is a more than good enough use case to make it worth publishing an API.
By all means improve the API if you can, but having one at all is the most important thing. And as people start using it they'll naturally map out the use case space and you can see what cases come up - rather than trying to figure out which interfaces people will need up front, it's much more efficient to respond to feature requests as they arise.
Disagree. The most important thing by far is to have an API at all. Just being able to build your main site but with a different UI (or as a native program) is a more than good enough use case to make it worth publishing an API.
By all means improve the API if you can, but having one at all is the most important thing. And as people start using it they'll naturally map out the use case space and you can see what cases come up - rather than trying to figure out which interfaces people will need up front, it's much more efficient to respond to feature requests as they arise.