LangSmith is LangChain's observability and evaluation platform. It logs traces, lets you debug chains, run evaluations, and monitor production LLM applications. Cost tracking is a feature, not the focus.
LangSmith's Strengths
- Deep tracing — See every step in a LangChain/LangGraph chain with input/output at each node
- Evaluation — Run automated evals against datasets to measure quality
- Prompt playground — Test prompt variations with side-by-side comparison
- LangChain integration — First-class support if you're in the LangChain ecosystem
AgentBurn's Strengths
- Cost-first design — Every feature is built around understanding and reducing spend
- Framework-agnostic — Works with any agent framework (CrewAI, AutoGen, custom)
- Multi-provider tracking — LLMs, compute, tool calls, everything in one view
- Budget governance — Per-agent alerts and spend limits
- Self-hosted and MIT — No vendor dependency
The Key Difference
LangSmith answers: "Why is my agent giving bad responses?" AgentBurn answers: "Why is my agent costing so much?"
LangSmith is a debugging and quality tool. AgentBurn is a financial management tool. They solve different problems.
Comparison
| Feature | AgentBurn | LangSmith |
|---|---|---|
| Cost tracking | Primary focus | Secondary feature |
| Trace debugging | No | Yes |
| Evaluations | No | Yes |
| Framework lock-in | None | Best with LangChain |
| Non-LLM costs | Yes | No |
| Self-hosted | Yes (MIT) | Enterprise only |
| Free tier | Unlimited (self-hosted) | 5K traces/month |
Using Both
LangSmith for debugging and quality. AgentBurn for cost management. Many teams use both — LangSmith tells you if your agent is working correctly, AgentBurn tells you if you can afford to keep running it.