I am not aware of anything that works today, but I think that there's room for shopping agents. Say you need a new USB Stick or a pair of shoes. Something between $10 and $1000 that you simply have to buy ASAP but doesn't warrant spending one or more evenings on research. A language model could sift through the descriptions and comments and try to eliminate trash and even outright fraud.

But then again, it's just another search engine, essentially. So for how long would it stay useful before it accepts payments to promote certain offers?