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mediumLangChainOpenAI

LangChain, LlamaIndex, LangGraph, what are the real differences, and when would you use each?

Asked constantly in GenAI loops, and most answers are marketing-page recitals. The version that scores: classify by what each actually is, data framework, integration toolkit, graph runtime, then give the selection criteria that outlive all three names.

Updated Aug 2026 · Grounded in real Forward Deployed Engineer interview loops and written to a senior-engineer editorial bar.

Asked constantly in GenAI loops, and most answers are marketing-page recitals. The version that scores: classify by what each actually is, data framework, integration toolkit, graph runtime, then give the selection criteria that outlive all three names.

20 answers per topic instead of 10, plus saved progress and bookmarks · no cardor unlock all 523 remaining answers · ₹2,000 / $25
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