Compare software

TruLensLangSmith
Free

Free and open source.

 Freemium

Can be tried for free, with paid plans listed on its pricing page.

Windows, macOS, Linux Web
  • OpenTelemetry-native tracing of every agent step
  • Judges explain their scores, not just give numbers
  • Detailed step-by-step agent tracing
  • SDKs for Python, TypeScript, Go and Java
  • Aimed at developers comfortable writing code
  • LLM judges add their own model calls and cost
  • Proprietary hosted service
  • Self-hosting requires Kubernetes
Downloadable app Self-hosted, Hosted service
Open source Closed source
License not stated License not stated
Not stated if an account is needed Account needed
Not stated if it works offline Needs internet

Checked October 1, 2026

Checked September 26, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.