So say you want to get data from a RESTful web api, do you have to customize your generic REST client? Because everything I've ever written that called an external API had to know what it was looking for in advance. Like to interact with Twitter's API, I went to their documentation page and read up on what URL's to call for the information I needed.
If you want a client coupled to a specific service then you don't want REST, you want a classic client-server architecture, which is more or less the antithesis of REST. But everyone insists on calling it REST when it goes over HTTP, then they complain that the apple tastes nothing like an orange.