IBM Rational Team API is a unified, client-side Java API for ClearCase, ClearQuest, and Requisite Pro. In order to use this Eclipse based API, customers must have installed Version 7.0.0 of Rational ClearQuest client, ClearCase Web server, or RequistePro client.
I use ClearCase and ClearQuest at work, and they’re just dreadful products. The UI for ClearQuest is awful, the performance is poor and reliability has been questionable at best.