Hi r/AI_Agents!

I’m a full-stack dev (experienced with Hugging Face but new to agents) looking to build a RAG-powered AI chat feature. I’m trying to build a RAG (Retrieval-Augmented Generation) AI chat feature that will run through an ExpressJS API, which will connect first to a web frontend and eventually a mobile app.

The RAG setup will need to support:

• Vectorized data (PDFs and text)
• Structured data (CSV and JSON)

I’ve started exploring LangFlow, but I’ve also heard Mastra.ai and n8n.io recommended. Other platforms’ opinions:

• ChatGPT/DeepSeek: LangFlow
• Claude: Mastra ai

Questions

1. Which framework fits best for my use case?
2. Which is easiest to learn?
3. Any (current) tutorials (especially for multi-format RAG like PDF + CSV/JSON)?