If you want to control anything in the IDE, but do so from an independent stand alone project, then I can only think of mouse and key input.
I haven't done much with that package, so I can't advice further on it.
Mouse and Key, relies on the target IDE config. I.e. if you send a key, but the user changed the keymap....
MS Windows also has some API, where you can access TWinControls of another app. Some GetWindow function, and you can query the caption, send keys, ..... But that is from very distant memory too, so again for your own research (and not sure what is on *nix).
The IDE has no remote API, but you could write a package, that gets installed in the IDE and takes remote commands.