LangSmith is an agent engineering platform designed to help teams observe, evaluate, and deploy AI agents throughout the development lifecycle. It provides native tracing for popular agent frameworks and OpenTelemetry, with SDKs for Python, TypeScript, Go, and Java. The platform captures production traces, turns them into test cases, and scores agents using LLM-as-judge evals and human feedback. For deployment, LangSmith offers an agent server with memory, conversational threads, and durable checkpointing, supporting human-in-the-loop interactions, A2A & MCP protocols, and scalable distributed runtimes. Additionally, LangSmith Fleet allows non-technical users to create and run agents across daily tools using plain language, with enterprise security and admin controls. LangSmith is complemented by open-source frameworks: LangChain for quick agent building with any model, LangGraph for low-level control and reliability, and DeepAgents for long-running autonomous agents.
Key Benefits
- Native tracing for popular agent frameworks and OpenTelemetry
- Reusable LLM-as-judge and multi-turn evals
- Supports human-in-the-loop and scalable distributed runtime
- Fleet enables non-technical users to create agents with plain language