It's using the web search provided by openai. Importantly this doesn't actually guarantee that it does any kind of search. I'm confused as to whether they're

It's using the web search provided by openai. Importantly this doesn't actually guarantee that it does any kind of search. I'm confused as to whether they're using the API or not. Afaik only the assistant API has access to the web search, so I would expect this was manually done? But then the reason for only doing this with openai is that the others don't provide an API > GPT- 4 (RAG) refers to GPT-4’s web browsing capability pow- ered by Bing. Other RAG models such as Perplexity.AI or Bard are currently unavailable for evaluation due to a lack of API access with sources, as well as restrictions on the ability to download their web results. For example, while pplx-70b-online produces results with online access, it does not return the actual URLs used in those results. Gemini Pro is available as an API, but Bard’s implementa- tion of the model with RAG is unavailable via API.