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orchestrator
Open source
free (OSS) + Arize cloud

Phoenix (Arize AI)

Open-source LLM tracing + evaluation. OpenInference standard for traces; runs locally with one pip install. The OSS-first pick for teams that want LangSmith-shaped functionality without vendor lock-in.

By Fredoline Eruo·Last verified May 6, 2026·7,000 GitHub stars

Overview

Open-source LLM tracing + evaluation. OpenInference standard for traces; runs locally with one pip install. The OSS-first pick for teams that want LangSmith-shaped functionality without vendor lock-in.

Stack & relationships

How Phoenix (Arize AI) relates to other entries in the catalog — recommended pairings, alternatives, dependencies, and edges to avoid. Each edge carries a one-line operator note from our editorial team.

Phoenix (Arize AI) ↔ ecosystem

Recommended stack

  • Pairs with
    OpenHands

    Phoenix instruments OpenHands tool-calls + LLM spans via OpenInference. Drop-in for trace + eval workflows.

  • Pairs with
    vLLM

    vLLM exposes OpenInference-compatible spans; Phoenix consumes them directly. The default OSS observability pairing for self-hosted vLLM deployments.

Alternatives

  • Alternative to
    LangSmith

    Phoenix is OSS (Apache 2.0) with OpenInference traces; LangSmith is closed-source with deeper LangChain integration. Pick Phoenix for vendor-independence.

  • Alternative to
    LangSmith

    LangSmith for the LangChain-native path; Phoenix for the OSS/OpenInference path. Pick by ecosystem fit and self-hosting requirement.

Pros

  • OSS, Apache 2.0
  • OpenInference standard for traces
  • Strong span visualization

Cons

  • Eval coverage trails LangSmith
  • Cloud dashboard requires Arize account

Compatibility

Operating systems
macOS
Linux
Windows
GPU backends
n/a
LicenseOpen source · free (OSS) + Arize cloud

Get Phoenix (Arize AI)

Official site
https://phoenix.arize.com
GitHub
https://github.com/Arize-ai/phoenix

Frequently asked

Is Phoenix (Arize AI) free?

Phoenix (Arize AI) has a paid tier (free (OSS) + Arize cloud). Check the pricing page for current terms.

What operating systems does Phoenix (Arize AI) support?

Phoenix (Arize AI) supports macOS, Linux, Windows.

Which GPUs work with Phoenix (Arize AI)?

Phoenix (Arize AI) supports n/a. CPU-only inference is also possible but slow.

Reviewed by RunLocalAI Editorial. See our editorial policy for how we evaluate tools.