With almost all of these papers, "RAG" is mentioned as a well-defined, absolute strategy. Is there an agreed upon implementation for it? Because as I have been building my own implementation, I have found that finding the right things to retrieve and augment the prompt with is incredibly challenging.

It seems to me that a great RAG would almost always outperform other strategies because it will be like giving the student a note with the answer right before the exam, compared to letting them read the whole curriculum, but I am very much still learning..