Phoenix
Open-source platform for AI agent development and evaluation.
Pricing: open_source : Free to use · Visit website
Phoenix by Arize is an open-source platform designed for AI engineers and Fortune 500 companies to develop, trace, evaluate, and iterate on AI agents. It provides tools for tracing, evaluating agent quality, testing changes with evidence, and integrating coding agents.
Pros
- Open-source
- Comprehensive evaluation features
- Agent development and tracing
Cons
- Steep learning curve
- Limited community support
FAQ
Is Phoenix free?
Yes, it's open source.
What is PXI?
PXI is the AI engineering agent inside Phoenix.
Can I self-host Phoenix?
Yes, it supports self-hosting.
Top alternatives
LLM Evaluation helps improve AI agents through observability and evaluation.
LLM Evaluation offers paid features for assessing large language models, complementing Phoenix's open-source developer tools.
Opik by Comet for AI observability and optimization.
Opik offers a freemium model with additional features for paid plans, while Phoenix is open source with no upfront costs.
Self-healing observability for AI agents.
TraceRoot AI offers a freemium model with advanced debugging features, complementing Phoenix's open-source capabilities.
AI engineering platform for tracing and evaluating LLM applications.
Langfuse offers free logging and monitoring for LLM integrations, similar to Phoenix's open-source developer tools.
Benchmark and monitor AI systems with research-backed metrics.
LLM Benchmarks offers a paid service to evaluate large language models, complementing Phoenix's open-source developer tools.
Last updated: 2026-10-31