LangGraph — a low-level orchestration framework for stateful, long-running LLM agents, built as a Python monorepo. libs/ ships eight independently versioned PyPI packages: the langgraph core runtime, langgraph-prebuilt agent APIs, a checkpointer family (base interfaces, Postgres and SQLite savers, a shared conformance suite), the langgraph-cli deployment tool, and the langgraph-sdk server client. Board grain: container-grade — each package is an opaque drill-down into its own L1 board.