LangSmith
The all-in-one developer platform for debugging, evaluating, and monitoring LLMs
★ 4.9 Rating (2100 reviews)
Freemium
$0 (Developer Free) / $39/mo
Detailed Overview
LangSmith provides complete observability for LLM applications. From local development to production monitoring, LangSmith lets engineers trace nested chains, inspect prompt inputs/outputs, run automated evaluations on datasets, and track costs.
Pros
- ✓ Zero-config tracing for any LangChain or LangGraph application
- ✓ Interactive prompt playground and dataset benchmarking
- ✓ Granular cost and token attribution per customer
Cons & Limitations
- ✗ Most powerful when tied to the LangChain ecosystem
- ✗ High-volume production traces can require sampling
Key Capabilities & Features
- • Nested execution trace visualization
- • Automated offline evaluation suites
- • Human feedback collection (thumbs up/down)
- • Token usage & cost dashboards
Who is LangSmith Best For?
AI engineers building production apps who need to debug why an agent hallucinated or failed a tool call.