Build Your First RAG App with Python + LlamaIndex — Step-by-Step Tutorial (2026)
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Build Your First RAG App with Python + LlamaIndex — Step-by-Step Tutorial (2026) Large language models know a lot, but they do not know your data. Ask Claude or GPT about your company's internal docs, your research papers, or last quarter's reports and you get confident-sounding nonsense. Fine-tuning is expensive, slow, and overkill for most use cases. RAG — Retrieval-Augmented Generation — is how you fix this. RAG is simple in concept: before the LLM generates an answer, your applic