AhmadZain80/FastAPI-RAG-Pipeline ? reverse-engineered prompt

Build me a FastAPI app that works like a secure document chat assistant.

I want users to be able to register and get a unique user ID, upload PDF, DOCX, or TXT files, and then ask questions about only their own documents. The app should store and search the uploaded content in a vector database, split files into chunks, and use retrieval plus an LLM to give clear answers with citations from the source text. Please make the chat endpoint feel smart, so it can decide how much context to pull back based on the question, and keep user data isolated so one person cannot see another person’s documents.

Use Groq with the Llama 3.3 model for the answer generation, and make sure the API is easy to try from Swagger docs. If anything is unclear, look up current docs online if you need to, and build it in a clean way that is ready to run locally with a simple setup.