LangChain Reference home page

GitHub
Main Docs

Overview
Client
AsyncClient
Run Helpers
Run Trees
Evaluation
Schemas
Utilities
Wrappers
Anonymizer
Testing
Expect API
Middleware
Pytest Plugin
Deployment SDK

⌘I

LangChain Assistant

Ask a question to get started

Enter to send•Shift+Enter new line

Menu

Overview Client AsyncClient Run Helpers Run Trees Evaluation Schemas Utilities Wrappers Anonymizer Testing Expect API Middleware Pytest Plugin Deployment SDK

Language

Theme

PythonlangsmithTesting

Testing

LangSmith testing utilities for logging inputs, outputs, and feedback from within pytest test cases. Use @pytest.mark.langsmith to run evaluations as tests.