A agentindex
Comparison

Langfuse vs LangSmith

A like-for-like, spec-level comparison. Both entries are verified against their docs and repo.

Langfuse

The most-used open-source LLM observability tool.

  • + Open source and self-hostable
  • + Framework-agnostic via OpenTelemetry
  • − Self-hosting ClickHouse is operational work
  • − Eval features trail dedicated eval tools

LangSmith

LangChain's observability and eval platform.

  • + Best-in-class when you already use LangChain
  • + Strong tracing UX
  • − Proprietary and cloud-only
  • − Vendor lock-in to LangChain
Spec Langfuse LangSmith
Category eval-observability eval-observability
License MIT Proprietary
Open source Yes No
Self-hostable Yes No
MCP support No No
Pricing freemium freemium
Starting price Self-host free; cloud tier Free developer tier
Models multi multi
Languages python, typescript python, typescript
GitHub stars 29.8k —
Last activity 2026-06-25 —