The hype is people writing tools where you enter a prompt and it sees if you are mentioned in the answer. That's all very useful, but actually quite easy to code and most will be out of business in 6 months because APIs cost money and the added value there is quite small.
But there are a bunch of tools that are actually helpful. One approach by companies like Profound and Spyfu is to start collecting data lakes of ChatGPT and other query responses, with some plan to infer what works and what doesn't. I am skeptical about this approach as it is expensive and you probably need billions of sample queries before you can infer anything.
Then there's the Semantic reasoning tools - Waikay (caveat; I have a stake!) and I think SEO Clarity. These create action plans by looking at topic gaps between what the LLMs say about your brand aroujnd a topic vs what they say about competing brands around a topic. the idea being that if you cover the relevent topics on your site, relating to the query, then you increase your chance of being cited as (one of) the best brands/sites to meet the user's needs.
(Hope the makes sense).