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Tracing Configuration

LangSmith tracing settings for observability and debugging.

VariableDefaultSensitiveDescription
LANGSMITH_TRACINGfalseNoEnable LangSmith tracing.
LANGSMITH_API_KEY(empty)YesLangSmith API key.
LANGSMITH_PROJECTlamb-agentNoLangSmith project name.
LANGSMITH_API_URLhttps://api.smith.langchain.comNoLangSmith API endpoint.
LANGSMITH_SAMPLE_RATE1.0NoTracing sample rate (0.0 to 1.0).

Example

bash
LANGSMITH_TRACING=true
LANGSMITH_API_KEY=lsv2_pt_xxxxxxxxxxxxx
LANGSMITH_PROJECT=lambchat-prod
LANGSMITH_SAMPLE_RATE=1.0

TIP

  • Set LANGSMITH_SAMPLE_RATE to 0.1 in production to trace only 10% of requests
  • Use LANGSMITH_PROJECT to organize traces by environment (e.g., lambchat-dev, lambchat-prod)
  • Access your traces at smith.langchain.com