LangSmith
ObservabilityProprietary · Proprietary (platform); LangChain SDKs are MITManaged only
LangChain's proprietary tracing, evaluation and monitoring platform.
LangSmith is LangChain's proprietary platform for tracing, evaluation and monitoring of LLM applications, generally available since February 2024; self-hosting is an Enterprise-only option, and in 2026 it introduced SmithDB, a Rust-based data layer the vendor says delivers a P50 latency of 92ms.
Caveat: Proprietary SaaS; self-hosting is limited to Enterprise agreements. The underlying LangChain/LangGraph SDKs are separately MIT-licensed.
Key facts
| Category | Observability |
|---|---|
| License | Proprietary (platform); LangChain SDKs are MIT |
| Language | N/A (managed platform) |
| Self-hosted | No |
| Last verified | 2026-10-04 |
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