Unlike Directors own handler menu, this tool lists not only Moviescript handlers, but rather all three types of scripts:
Unlike Directors handlername menu the handlers are not listed all in one single menu, but they are categorized by the scriptmembers, they appear in.
There's also a submenu which lists the scripts used by the sprites in the current frame. So you can quite easily send an event to a sprite on stage. Note, that the scriptlist is used, rather than the scriptinstancelist for two reasons: It exists, if the movie is not running and querying the scriptinstancelist of a sprite with an empty scriptinstancelist puppets the whole channel and makes it unresponsive furtheron. As the script goes through each sprite to build the list this could only be avoided using the D10 syntax "makeScriptedSprite". I decided to go with the scriptlist, which has the downside of not listing dynamically added behaviors, but hey... ;-)
Another important difference is, that handlers get executed by default and only the use of a modifier key either shows the occurrence in the script editor (Option/Alt key) or copies the syntax into the clipboard (Shift key).
So this tool provides an easy way of using your own scripts for authoring without needing to remember the names and type the same handlernames over and over again into the message window. It provides also a way to sendSprite() events, by simply selecting the event from the menu and entering the parameters in an upcoming dialog.