---
id: langsmith
version: "0.10.18"
license: MIT
license_treatment: permissive
maintenance: active
---

# langsmith — Client library to connect to the LangSmith Observability and Evaluation Platform.

License: permissive · Maintenance: active · Popularity: top 1,000 on PyPI

## Install

pip install langsmith
uv add langsmith
poetry add langsmith

## Description

# LangSmith Client SDK

[![Release Notes](https://img.shields.io/github/release/langchain-ai/langsmith-sdk?logo=python)](https://github.com/langchain-ai/langsmith-sdk/releases)
[![Python Downloads](https://img.shields.io/pypi/dm/langsmith)](https://pypi.org/project/langsmith/)

This package contains the Python client for interacting with the [LangSmith platform](https://smith.langchain.com/).

To install:

```bash
pip install -U langsmith
export LANGSMITH_TRACING=true
export LANGSMITH_API_KEY=ls_...
```

Then trace:

```python
import openai
from langsmith.wrappers import wrap_openai
from langsmith import traceable

# Auto-trace LLM calls in-context
client = wrap_openai(openai.Client())

@traceable # Auto-trace this function
def pipeline(user_input: str):
    result = client.chat.completions.create(
        messages=[{"role": "user", "content": user_input}],
        model="gpt-3.5-turbo"
    )
    return result.choices[0].message.content

pipeline("Hello, world!")
```

See the resulting nested trace [🌐 here](https://smith.langchain.com/public/b37ca9b1-60cd-4a2a-817e-3c4e4443fdc0/r).

LangSmith helps you and your team develop and evaluate language models and intelligent agents....

## AI interpretation — verify before relying

LangSmith is a Python client SDK for the LangSmith observability and evaluation platform, enabling you to trace, debug, and evaluate language model applications with automatic instrumentation and benchmark evaluation capabilities.

Verdict: Actively maintained, permissively licensed, and dependency-light for its scope. Zero known vulnerabilities and top-1000 popularity tier make it a safe choice for teams adopting LangSmith observability. The 14 runtime dependencies are standard (httpx, pydantic, requests) and well-vetted.

[View on SkillFed](https://skillfed.io/packages/langsmith) · [View on PyPI](https://pypi.org/project/langsmith/)