Info on SmartFunctions

Is there perhaps documentation or example code available that shows how to use the SmartFunctions of BlackPearl for implementing business-rule logic? For instance, how would you define a business rule as a SmartFunction and then evaluate it? I have browsed through the types defined in the “SourceCode.SmartFunctions.Client” assembly, and I presume you would use the SmartFunctionClientServer class for some of this. The concept of “facts” also seems to play an important role, but how does all of this work?