LlamaIndex

LlamaIndex is a data framework for building LLM applications that connect language models to private and enterprise data. It provides tools for ingesting, indexing, and retrieving documents, powering retrieval-augmented generation, agents, and complex document workflows. Its open-source libraries are widely used, and LlamaCloud offers managed parsing, indexing, and retrieval for production teams.

LlamaIndex is popular with developers building question-answering systems, chatbots, and document automation over unstructured data. It handles the messy work of loading data from many sources, chunking and embedding it, and retrieving the right context for a query. LlamaParse, its document parsing service, is a common entry point for teams dealing with complex PDFs and spreadsheets.