By LangChain

LangChain

LangChain

The original LLM-app framework — standard model/tool interfaces, hundreds of integrations, and the create_agent prebuilt that compiles to a LangGraph agent

LangGraph

LangChain

Graph-based orchestration for stateful, multi-step agents with branching, loops, and human-in-the-loop

LangSmith

LangChain

LangChain's hosted platform for tracing, evaluating, and monitoring LLM and agent apps (works with or without LangChain)