OpenCairn

OpenCairn is an open-source AI knowledge OS that turns notes, documents, and web sources into a connected workspace for search, answers, writing, and agent workflows. Unlike a simple note app or chatbot, it is built for source-grounded knowledge work: ingest files, ask questions with context, trace answers back to sources, generate artifacts, and run workflows across your workspace. It is self-hostable, multi-LLM friendly, and designed for control over your data and tools.