1. A computer-implemented method of providing an information model for a control system, the information model facilitating communication of information among agents of the control system, the method comprising: under control of a control system executing on one or more physical computing devices: providing information in an information model comprising a hierarchy of information objects, the information objects comprising one or more fields defined using abstract primitives in a schema, at least one of the information objects having a first form and a second form that is different from the first form, the information model stored in a computer-readable medium accessible by the control system; associating a publishing agent with a first subset of the information objects in the hierarchy, the first subset representing information that the publishing agent can produce for other agents, the publishing agent interacting with the one or more fields of the information objects in the first subset; associating a subscribing agent with a second subset of the information objects in the hierarchy, the second subset representing information that the subscribing agent can request from other agents, the subscribing agent interacting with the one or more fields of the information objects in the second subset; and communicating, by the control system, to the subscribing agent information produced by the publishing agent if there is at least one information object in common between the first subset and the second subset, wherein neither the subscribing agent nor the publishing agent directly interacts with the control system, the subscribing agent and the publishing agent instead interacting with the one or more fields of their respective associated information objects, wherein each of the information objects is responsible for and isolates from the associated publishing or subscribing agent the interaction with the control system, and wherein the information is communicated to the subscribing agent without requiring knowledge by the subscribing agent of the publishing agent prior to the communication and without requiring knowledge by the publishing agent of the subscribing agent prior to the communication.