Framework
Phoenix
Phoenix is an open-source AI framework, launched in 2022, made for developers and businesses.
An open-source tool for tracing, evaluating and debugging LLM apps and agents.
Main jobs: Evaluate and trace LLM apps. It is open source and free to use. You can use it on your own server, offline on your own machine, through an API and in the terminal.
Markdown version of https://godooo.ai/en/framework/phoenix. Every page on this site has one: add .md to its address.
At a glance
- Type
- Framework
- Launched
- 2022
- Galaxy
- Models & APIs
- Open source
- Yes
- Source code
- github.com/Arize-ai/phoenix
- GitHub stars
- 11,600
- How you run it
- Self-host · Runs offline · API · Terminal
- Made for
- Developers · Businesses
- Website
- arize.com
- Also known as
- Arize Phoenix
What it can do
Evaluate and trace LLM appsmain jobunconfirmed
“Evaluation - Leverage LLMs to benchmark your application's performance using response and retrieval evals.”— github.com, 2026-09-24
Prompt optimizationsupportedunconfirmed
“Playground - Optimize prompts, compare models, adjust parameters, and replay traced LLM calls.”— github.com, 2026-09-24
unconfirmedproposed by a machine, awaiting calibration
Alternatives
- LangfuseOpen source, freeAlso does: Evaluate and trace LLM apps, Prompt optimization
- DeepEvalOpen source, freeAlso does: Evaluate and trace LLM apps
- promptfooOpen source, freeAlso does: Evaluate and trace LLM apps
- RagasOpen source, freeAlso does: Evaluate and trace LLM apps
- Pydantic AIOpen source, freeAlso does: Evaluate and trace LLM apps
Questions
What is Phoenix?
Phoenix is an open-source AI framework, launched in 2022, made for developers and businesses. An open-source tool for tracing, evaluating and debugging LLM apps and agents.
Is Phoenix free?
Yes. Phoenix is open source and free to use.
Is Phoenix open source?
Yes. The source code is at https://github.com/Arize-ai/phoenix.
Can Phoenix run locally?
Yes. Phoenix can run offline on your own machine. It can also be self-hosted on your own server.
What can Phoenix do?
Main jobs: Evaluate and trace LLM apps. It can also do: Prompt optimization.
What are open-source alternatives to Phoenix?
Open-source ones: Langfuse, DeepEval, promptfoo, Ragas and Pydantic AI.
Sources
- github.com/Arize-ai/phoenixchecked 2026-09-24
- arize.com/docs/phoenix