For an interview or business in general it is always a good idea to carry a pen , pencil , or both.  Carry only gold or silver.

If you are disorganized , cannot seem to handle responsibility and demands it can be an issue or a harbinger.  It can be arbritary.    Under no circumstances , should you carry cheap ballpoint pens that may be on sale on Staples big box store or whatever.  Even if the firm is highly cost conscious - the type where the door squeaks from lack of oil - due to the cost of that oil or wd 40. - then it is not a good idea .  There will be plenty of time after you are hired for cost saving and cost  saving memos that you will get from upper management.