Hi I have created custom template for blog generating using custom prompt, blog title and description, keywords, model selection, files (1 pdf file per blog optionla)  and urls (3 per blog to be semantic searched in keyword context and use relevant snippets with link). 
I have explored all the API end points for automation of this template based on google spreadsheet or form submissions.. where these fields (including url links) will be passed on and blog post to be generated based on call. 
Which API end points to use - Agent ot Prompt completion. How to use agent with url.. it gave me an error that RAG has not been defined - is rag mandatory??