LlamaIndex

LlamaIndex is an open-source framework for building data-backed and agentic LLM applications, formerly known as GPT Index. It provides connectors for ingesting data, indexing structures, and query engines that retrieve relevant context to augment model responses, the core of retrieval-augmented generation. It integrates with many models and vector stores and pairs with the LlamaParse service for document parsing. Released under the MIT license.