LangSmith API reference - Docs by LangChain

The LangSmith REST API provides programmatic access to LangSmith platform features including tracing, datasets, experiments, annotations, and more. Browse the full API reference in the LangSmith REST API section in the sidebar.

Authentication

Pass the X-Api-Key header with each request. The value should be a valid LangSmith API key.

curl --request GET \
  --url https://api.smith.langchain.com/api/v1/workspaces \
  --header 'X-Api-Key: LANGSMITH_API_KEY'

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​Authentication

Authentication