The plotscripting dictionary is a complete listing and documentation of available plotscripting commands and HamsterSpeak built-in functions and flow control constructs. (However, aside from the flow control constructs it does not document the HamsterSpeak scripting language itself, that's the purpose of the HamsterSpeak Specification.) A scan through is recommended to confident new plotscripters to get an idea of what their scripts could do.
The correct version of the dictionary is packaged with engine downloads as docs/plotdictionary.html. It's also available online: