LlamaIndex

LlamaIndex is an open-source data framework for building retrieval-augmented generation and agent applications on private data. It provides connectors for PDFs, databases, Notion, Slack, Google Drive and hundreds of other sources, plus parsing, chunking, indexing and query tools that feed clean context into any large language model. LlamaCloud adds managed parsing and hosted indexes for production teams. Developers choose it when accurate document question answering, enterprise knowledge assistants or research agents matter more than raw prompt engineering.