LangChain

LangSmith Evaluation

Evaluation and observability features of the LangSmith platform for testing agents on datasets and scoring production traces.

Proprietary (open source SDK)PythonTypeScriptv0.14.5

What it supports

  • Evaluates multi-step agents and tool calls: supportedEvaluates multi-step agents and tool callsDocs
  • LLM as a judge scoring: supportedLLM as a judge scoringDocs
  • Tracing: supportedTracingDocs
  • Runs in CI: supportedRuns in CIDocs

Install

pip install langsmith

Links

Official documentationgithub.com/langchain-ai/langsmith-sdkHosted option: LangSmithPricing

Other eval frameworks

Inspect AIpromptfooDeepEvalPydantic EvalsHarborLangfuseOpikMLflow GenAI EvaluationArize PhoenixW&B WeaveRagasGoogle ADK EvaluationBraintrustMicrosoft Foundry EvaluationsGen AI Evaluation Service

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Reviewed Oct 9, 2026.