Directory / Phoenix
Phoenix
Verified
Arize’s open observability and eval notebook for LLM apps.
Phoenix is an open-source observability and evaluation tool from Arize: traces, evaluations, datasets, often run as a notebook or local app. Arize AX is the commercial platform and is not a separate listing.
- Model independence
- Multi-model
- Deployment
- Self-hosted
- Open source
- Yes
- License
- Elastic License 2.0 (read the repo)
- Pricing model
- Mixed
- Added / updated
- 19 Aug 2026 / 19 Aug 2026
phoenix.arize.com · Docs · Source
Editorial take
Phoenix is the open Arize artifact. ELv2 is not MIT — read it. Good for tracing and evals you run yourself. Do not add an Arize AX listing unless we need the commercial SKU separately; we do not.
Strengths
- Open tracing/eval focused on LLM apps.
- Works locally without buying AX.
- Eval + observability in one tool.
Limitations
- Elastic License is not OSI-casual.
- Commercial platform is a different contract.
- Not a coding agent.