class Gladys::Script

def defined_options

and run the block to get the options.
Check for the provided option set, or default to "default" (if it exists)

def defined_options
  @defined_options ||= begin
    block = @option_sets[@option_set.to_sym] if @option_set
    block ||= @option_sets[:default]
    block&.call
    Struct.new(*@definitions.keys).new(*@definitions.values)
  end
end