I've replaced the STDERR.puts methods for a simple wrapper over ruby's Logger class. This allows users to quiet the API output if they wish. It also leaves the door open to add more logging and error handling at different levels if desired.
I also provided a set method for clients to inject their own logger; useful if you happen to be in a larger application with its own object providing a Logger interface (as I happen to be) and you want the API traffic to be included in the application-wide stream.
add a logger class and spec
use Rype::Logger in api log methods