class Rails::Generators::Base

def self.desc(description = nil)

root otherwise uses a default description.
Tries to get the description from a USAGE file one folder above the source 
def self.desc(description = nil)
  return super if description
  @desc ||= if usage_path
    ERB.new(File.read(usage_path)).result(binding)
  else
    "Description:\n    Create #{base_name.humanize.downcase} files for #{generator_name} generator."
  end
end