With COM plugins, each plugin point exposes some specific interfaces. The inputs and outputs available for your computation depend on the plugin point, and are available through these interfaces. For instance, the figure below is the class diagram of a COM access constraint plugin. For that plugin point the interface that the plugin is required to implement is the IAgAccessConstraintPlugin interface.
The figure below outine the interfaces offered by the
IAgAccessConstraintPlugin plugin point.
Supporting interfaces that provide some key functionality, are available for all COM Engine plugins, such as:
The figure below outlines those supporting interfaces.
STK 11.2.1 Programming Interface