Given improvements in underlying LLMs used by our NLQ feature, it's very likely that passing indexes would now improve the performance and accuracy of generated NLQ results. 

We should test this assumption to confirm this is true before merging these changes. 

We can also modify the hardcoded prompt to guide the LLM to employ the $search or $vectorSearch stages if indexes of those types exist in this collection and those stages seem appropriate to include based on the user's prompt. 

After this investigation, let's file a followup ticket to do the implementation.