Discussion on Custom Function Support for Evals in Arize

I am looking at this: https://docs.arize.com/phoenix/api/evals#returns-2 Is there any interest in supporting uploading a custom function calling / structured generation schema for evals such that the user can upload your own custom schema and then arize evaluate that off of whatever custom metric the user configures. Id imagine this would be so involved for the user that there would be no value to such an interface instead i think it should be delegated to the user to generate their own `generations_dataframe`. Kinda thinking out loud here but curious to see how yall think of evals.