RAG Customer Support Chatbot

A fully functional GPT-powered customer support chatbot using Retrieval-Augmented Generation (RAG). User queries are matched against a product knowledge base (returns policy, shipping, payments) — the top-k relevant chunks are injected into the system prompt before the LLM responds. Built with Next.js 15 App Router, AI SDK v6, and streaming responses. Falls back to scripted demo responses when no OpenAI key is set, so the live demo always works.