What role does the Abhidhamma play in Buddhist hermeneutics?

I often see the Abhidhamma referenced as a framework for interpreting the teachings of the suttas. However, opinions vary widely: some say it is essential for proper interpretation, while others argue that it is a later analytical system not required for understanding the early discourses. How exactly does the Abhidhamma function within Buddhist hermeneutics? Do canonical or commentarial texts explicitly state how the Abhidhamma should be used to interpret other teachings? And if yes How do traditional commentaries justify its authority? Furthermore Are there examples where Abhidhamma exegesis diverges from sutta usage? If so How do scholarly commentators resolve such differences?