Sometimes it contains only a list of links. And sometimes the hit list includes the first few lines of the page. All of these styles of presentation can be very helpful. Quality of the Help Documentation Last but certainly not least, consider the quality of the help the index offers. You should be able to find a discussion of all strategies available on the index, and also the features discussed here.
Help is vital because of the wide range of abilities and features in search engines.
We can't remember every detail of every index, so the help should be easy to get to and completely discuss all strategies and features that are available.