We already have a when-to-retrieve classifier. Is a que...

While both are classifiers over the query, they serve different purposes. A when-to-retrieve classifier only determines if retrieval is necessary. A query router manages a more complex output space, mapping queries to specific retrieval operations. Furthermore, routing to ‘answer directly’ implicitly solves the when-to-retrieve problem, whereas a when-to-retrieve classifier provides no information on which of the multiple retrieval operations should be executed.