Updated March 9, 2026
LangSmith is LangChain's observability and evaluation platform for LLM applications. It provides detailed tracing of every LLM call, chain execution, and agent step—showing inputs, outputs, latency, token usage, and cost. LangSmith includes annotation queues for human feedback, dataset management for evaluation, and regression testing for prompt changes. It's the most comprehensive debugging tool for LangChain-based applications.
OpenObserve is an open-source observability platform for logs, metrics, traces, and LLM apps, priced per GB with no seat or host fees.
Core capabilities each platform advertises.
OpenObserveWhat each tool does well, and the limitations to keep in mind.
Pros
Cons
OpenObservePros
Cons
Choose LangSmith if you wantChoose if you want
Choose OpenObserve if you wantChoose if you want
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