Controllers communicate commands in terms of goals and constraints. A goal is an objective. A constraint is information regarding how the goal is to be achieved. For example, a constraint may specify when, or how much of, a resource may be used to achieve a goal. Additionally, or alternatively, a constraint may specify an acceptable or expected accuracy or tolerance regarding how the goal is achieved. Each controller is expected to achieve assigned goals in accord with associated constraints. Thereby, system communication may be reduced. If controllers achieve goals according to specified constraints, the controllers do not need to provide updates or be updated regarding the status of activities of other controllers or regarding other operational context information. In some embodiments, commands are generally not acknowledged. Instead, serving controllers respond to a command with an error message if a goal cannot be met in accord with an associated constraint.