Abstract: The subject application is directed to a system and method for extensible document processing. The startup of a plurality of document processing services on an associated document processing device is controlled via a service startup manager. Each of the document processing services is then interfaced with a control system via a device level interface. Data is communicated between the device level interface and an external data processing device via an agent layer interface. The agent layer interface is registered with the service startup manager. A startup of the document processing device is then commenced in accordance with the control of the service startup manager. A document processing control display is generated on a user interface associated with the document processing device, with the display including indicia corresponding to one of the functions of the external data processing device according to the agent layer interface.