LlamaIndex
Also: LlamaIndex
An open-source data framework specifically focused on connecting AI models to your documents and data — strong for building document indexing, retrieval, and question-answering pipelines. Complements LangChain (which is more general) with deeper specialization in the data ingestion and retrieval side. Good choice if your primary use case is 'Claude that knows about our internal documents' and you want a framework rather than building from scratch.
In practice
You want to build a tool that lets employees ask questions about your internal documentation. LlamaIndex handles the plumbing: loading your docs, splitting them into chunks, indexing them, and retrieving the right pieces when a question comes in — before passing them to Claude to answer. It's an orchestration tool specifically designed for document-heavy AI applications.
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