Blackboard Systems typically have a bit more formalism. There's a lot of different forms, but usually there's elements like Knowledge Sources, Triggers/Conditions, the Blackboard itself doing activation. It's a very interesting world, having some nice dataflow behaviors. There's similarity here & I'm glad to hear Blackboard Systems mentioned, but I want to encourage folks to look a little deeper at what typically is implied. https://en.wikipedia.org/wiki/Blackboard_system