Provide documentation about known variables / procedures on hover
When the user hovers of a specific procedure or variable or piece of code then the extension could show some information about that code, like when hovering over an API-command the extension would show the documentation for that command, or when hovering over a message port (e.g. "AdoScript") it could give some information about what kind of commands that message port provides.
For custom procedures and variables the documentation could be determined based on the comments provided ... before it? after it? there's no fixed way on how to document custom procedures etc. ala JavaDoc, but we could invent something for that. (e.g. using ## for comments or startinga multi-line comment with (** and ending with **) to provide that kind of documentation before the variable / procedure without an empty line in between).
Also see #5