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Tag #eval

Open-source LLM and agent observability — OpenTelemetry tracing and evals you can self-host

arize-phoenix-v20.8.02026-09-04PythonElastic-2.0
11.3k Open source Free tier Paid
Langfuse

Langfuse

Langfuse

Open-source tracing, evaluation, and analytics for LLM and agent applications

v4.30.02026-09-04TypeScriptMIT
34.2k Open source Free tier Paid
LangSmith

LangSmith

LangChain

LangChain's hosted platform for tracing, evaluating, and monitoring LLM and agent apps (works with or without LangChain)

SaaS / SDKProprietary
Free tier Paid