Hacker News Reader

No, it doesn't use langchain and yes it uses OpenAI.

Care to elaborate? I mean, looking at the source code it clearly does use LangChain for PDF ingestion https://github.com/mayooear/gpt4-pdf-chatbot-langchain/blob/...

He might mean the site chatpdf.com does not use langchain but uses the OpenAI API.

Yes, that's what I meant.