It is disclosed a printing agent container having ink an authenticity detection mechanisms comprising: a receptacle having a top wall a bottom wall opposing such top wall and a sidewall between such top wall and such bottom wall; an internal volume defined by such receptacle that contains a printing agent, and a vibration transducer on one of the side walls, wherein the container is to be mechanically coupled to a carriage so that the printing fluid is disposed on the bottom surface, being the vibration transducer to detect a vibration signal induced by the carriage and wherein the container comprises a communication channel to a controller being the controller to receive through the communication channel a container signature from the vibration transducer and to identify a container identification signal associated to the container signature.