LangSmith Observability

LangSmith is LangChain's native observability and monitoring platform designed for LLM applications. It captures detailed execution traces, logs all inputs/outputs, and provides structured debugging through a web dashboard. Every API call, chain invocation, and intermediate step is recorded, enabling engineers to reconstruct failures, measure latency, and optimize prompts in production. It bridges the gap between local development (where you can print outputs) and production (where you need systematic monitoring). It's used by ML teams building AI assistants, RAG pipelines, and agentic workflows.