I'm trying to throw up an error prompt.

I've tried:

var error = Dialog.prompt("Error", [
		{description: "Please select a path first"}
	]);

But it doesn't resize the Dialog to show the description text.. Only when I add something like:

{description: "a value", value: thevalue, width: 50},

But I don't need any values.. I just want a small warning..
Any ideas?