Resource / Observability

Arize Phoenix

An open-source tool for LLM tracing, evaluation and retrieval quality observability.

Free and open source

Open source and self-hostable; the hosted version's plans must be checked separately.

29 / 30

Strong Candidate · Maintenance risk 4/5

Last verified: 2026-08-28. A free tier is not a permanent commitment; re-check the official conditions before use.