2th of 4 Questions.
What's the max batch size and how do you retrieve results? — expected answer: results come back via a results_url on the batch object; you poll processing_status until it's done
The maximum batch size is 10,000 requests. Results are retrieved by polling the batch's processing_status until ended, then downloading from the provided results_url.
You can submit up to 10,000 requests in a single batch. After submitting, the batch processes asynchronously. To retrieve results, you must poll the batch endpoint to check its processing_status. Once the status is ended, the batch object will contain an results_url field. You then download the results file from this URL, which contains the outputs for each request in the order of your original custom_id values.
Batch Status Polling and Result Retrieval