I've used it once to suggest a specific term that I'm going to use in my comic. I was utterly incapable of formulating a conventional search query for a search engine so, after endlessly browsing various thesauri, in the end I resorted to asking perplexity ai. Still took a bit and I had to fight it to get it to understand what I was asking but I did eventually find a term that fits. Felt dirty afterwards. Does that count as "productive"?
The only other thing was the title of a book I read 30 years ago and had only vague memory of. So I gave it an approximate description including a plot point I thought I remembered. The first result it gave me wasn't it. But it claimed the plot involved the thing I remembered. I then asked again and the second result actually was the correct book - turns out I had almost completely misremembered the plot point but it still said "yep, this happens in this book". Very weird experience.