Phoenix
Trace, evaluate and debug LLM apps
LLM / RAG frameworkLLM observabilityElastic-2.0Runs locallyPythonIntermediate
🐳 Docker pulls
📦 PyPI downloads / month
📦 npm downloads / month
🚀 Latest release ·
What is Phoenix?
Phoenix from Arize traces LLM applications, surfaces failure clusters and runs evaluations, all runnable locally in a notebook or as a server.
Why people choose Phoenix
- Runs locally, even in a notebook
- Clusters failures to find patterns
- Built-in LLM evaluators
Phoenix at a glance
| Category | LLM / RAG framework |
| Type | LLM observability |
| License | Elastic-2.0 |
| Runs locally | Yes |
| Built with | Python |
| Skill level | Intermediate |
| Best for | finding why a RAG pipeline fails |
Latest releases
Open-source alternatives to Phoenix
Other open-source llm / rag framework tools worth comparing:
LangChainCompose chains, tools and agents
LlamaIndexThe data framework for RAG
HaystackProduction pipelines for search and RAG
DSPyProgram — not prompt — language models
txtaiAll-in-one embeddings database
RAGFlowDeep-document-understanding RAG
Semantic KernelMicrosoft's enterprise agent frameworkGraphRAGRAG that builds a knowledge graph first
LiteLLMOne API for 100+ LLM providers
InstructorReliable structured outputs from LLMs
OutlinesGuarantee valid JSON and grammars
GuidanceInterleave control and generation
LLMWareEnterprise RAG with small specialised models
FlashRankUltra-light reranking for better RAG
Sentence TransformersThe standard way to make embeddings
RagasMeasure whether your RAG is any good
PromptfooUnit tests for your prompts
LangfuseSee what your LLM app actually didPhoenix head-to-head
Phoenix vs LangChainPhoenix vs LlamaIndexPhoenix vs HaystackPhoenix vs DSPyPhoenix vs txtaiPhoenix vs RAGFlowPhoenix vs Semantic KernelPhoenix vs GraphRAGPhoenix vs LiteLLMPhoenix vs InstructorPhoenix vs OutlinesPhoenix vs GuidancePhoenix vs LLMWarePhoenix vs FlashRankPhoenix vs Sentence TransformersPhoenix vs RagasPhoenix vs PromptfooPhoenix vs Langfuse
FAQ
Is Phoenix free?
Phoenix is free and open-source (Elastic-2.0 license), so you can use, self-host and modify it at no cost.
Can I run Phoenix locally?
Yes. Phoenix is designed to run on your own machine or server, keeping your data private.
What is the best alternative to Phoenix?
Popular open-source alternatives include LangChain, LlamaIndex, Haystack. See the comparisons above to choose.
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