Arize AI

Arize Phoenix

Self-hostable platform for tracing, evaluating and experimenting on LLM apps and agents, built on OpenTelemetry.

Elastic-2.0 (source available)PythonTypeScriptv20.20.0

What it supports

  • Evaluates multi-step agents and tool calls: supportedEvaluates multi-step agents and tool callsDocs
  • LLM as a judge scoring: supportedLLM as a judge scoringDocs
  • Tracing: supportedTracingDocs
  • Runs in CI: supportedRuns in CIDocs

Install

pip install arize-phoenix

Links

Official documentationgithub.com/Arize-ai/phoenixHosted option: Arize AXPricing

Other eval frameworks

Inspect AIpromptfooDeepEvalPydantic EvalsHarborLangfuseOpikMLflow GenAI EvaluationW&B WeaveRagasGoogle ADK EvaluationBraintrustLangSmith EvaluationMicrosoft Foundry EvaluationsGen AI Evaluation Service

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Reviewed Oct 9, 2026.