Use simple yet unique titles: you want the title to be simple and easy to grasp, and you don't want two bugs to have the same title.
However, a bug summary should be synthetic. No need to specify the path or part of the description in it.
Although you need to be concise, you should include some key words or info (string IDs) in your summaries.
On the other hand, for No duplicates (also known as "dupes"), you don't want to create an entry for an issue that is already covered.