🔧 AI ProductivityOpen SourceFree

LangSmith

LangChain ops platform — tracing, debugging, testing, evaluation

4.5/ 5⭐ 8,000 GitHub starsPythonProprietary

⭐ Star on GitHub ☁️ Try LangSmith Free 🚀 Deploy on LangChain

📋 Overview

LangSmith is the official LangChain ops platform for tracing, debugging, testing, and evaluation of LLM applications. Unlike Langfuse (which is framework-agnostic), LangSmith is deeply integrated with LangChain — providing automatic tracing of chains, agents, and retrievers without manual instrumentation. It provides a visual debugger, dataset management, and evaluation pipelines. The platform is proprietary but has a generous free tier.

✨ Key Features

•Deep LangChain integration
•Automatic tracing of chains, agents, retrievers
•Visual debugger for step-by-step analysis
•Dataset management and evaluation pipelines
•Prompt versioning and A/B testing
•Free tier available
•Automatic instrumentation
•Prompt versioning

🎯 The Problem It Solves

LangChain applications are complex — chains of prompts, retrievers, and agents are hard to debug. LangSmith provides deep visibility into every step of a LangChain execution.

🔧 How It Works

LangSmith integrates automatically with LangChain — just set your API key and it traces every chain, agent, and retriever call. The visual debugger shows inputs/outputs at each step. The evaluation framework runs automated tests against datasets. The platform also supports prompt versioning and A/B testing.

🚀 Installation & Quick Start

Installation

See website

Quick Start

See documentation

✅ Pros

•Best LangChain integration
•Automatic tracing
•Visual debugger
•Evaluation pipelines
•Free tier
•Automatic instrumentation
•Prompt versioning

❌ Cons

•LangChain only
•Proprietary
•Free tier tight limits
•Limited free tier

💬 Practitioner Verdict

“LangSmith is the best choice for LangChain applications — the deep integration is unmatched. The trade-off: LangChain-only, proprietary, and the free tier has tight limits. For LangChain shops, LangSmith is the default.”