The Kofferklausur, Revisited

In September 2024, a colleague asked an audience: “What is RAG?” I answered: Kofferklausur [1].

For non-German speakers: a Kofferklausur is an open-book exam. You bring your textbooks, notes, everything. The exam doesn’t test what you memorized, it tests whether you can find the right information and reason about it under pressure.

That analogy stuck with me. A foundation model is the student. RAG is the suitcase full of books. The model doesn’t need to memorize every fact, it needs to know how to find the right one and reason about it. Special-purpose tools beat the Swiss Army knife.