Open-source agent tracing, evals and prompt management.
WebsiteProvisional comparison
Langfuse vs LangSmith
Both are provisional S-tier on Agent Observability & Evals. Rankings are never for sale.
Full Agent Observability & Evals tier list
| Field | Langfuse | LangSmith |
|---|---|---|
| Tier | S · provisional | S · provisional |
| Why | Leading open-source observability (35k+ stars), self-hostable. | Most established agent tracing/eval platform; framework-agnostic. |
| Pricing | open-source / freemium cloud · starts at $29/mo | freemium · starts at $39/seat/mo (Plus) |
| GitHub stars | 35,875 | — |
| Last push | Oct 15, 2026 | — |
| Last verified | Oct 15, 2026 | Oct 15, 2026 |