#1
L#1
Open-source LLM observability, tracing and evals.
Evals & observabilityopen-source
Best agent tracing & evals
Short answer: start with Langfuse — Open-source LLM observability, tracing and evals. Strong alternatives: LangSmith, Helicone.
Updated Oct 13, 2026 · How we rank
Editorial v0 order for "Best agent tracing & evals". Not benchmarked yet — scores will be published per the methodology once tested.
Ranked, not sold.
The ranking
3 tools
- #2L
Tracing, evaluation and monitoring for LLM apps.
Evals & observabilityfreemium - #3H
Open-source LLM observability and gateway.
Evals & observabilityopen-source
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Comparison table
| Rank | Tool | Pricing model | Integrations | Self-hostable | Last verified |
|---|---|---|---|---|---|
| 1 | Langfuse | open-source | API | Yes | Oct 14, 2026 |
| 2 | LangSmith | freemium | API | No / not listed | Oct 14, 2026 |
| 3 | Helicone | open-source | API | Yes | Oct 14, 2026 |
Head-to-head comparisons
FAQ
How is this ranking made?
By the published methodology: an independent editorial v0 ordering, not yet benchmarked. Rankings never change because a program pays.