Models

In this example, the text-davinci-003 is specifically used to generate text yes. If you did not pass in llm_predictor to the index constructor, it would still default to that.

And yes, in this example, text-ada-002 is being used to generate the embeddings

Basically, llama index uses an llm_predictor for text completion and an embed_model for generating embeddings

Usually, the token usage for embeddings is very high. So using a cheap model like text-ada-002 is a good default, because it's very cheap and works very well for generating embeddings