[How to use off-the-shelf evaluators (Python only) | 🦜️🛠️ LangSmith](https://docs.smith.langchain.com/evaluation/how_to_guides/use_langchain_off_the_shelf_evaluators_old): LLM should read this page when needing to use pre-built evaluators in LangSmith with Python, understanding evaluation options for different types of responses, or configuring evaluator parameters. This page documents how to use LangChain's off-the-shelf evaluators in LangSmith including QA evaluators, criteria evaluators, labeled criteria evaluators, string/embedding distance metrics, using custom LLMs for evaluation, and handling multiple input/output fields.

