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Tag #tracing

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

arize-phoenix-v19.4.02026-07-22PythonElastic-2.0
10.7k Open source Free tier Paid
Langfuse

Langfuse

Langfuse

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

v3.224.02026-07-22TypeScriptMIT
31.7k 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
Opik

Opik

Comet

Comet's open-source platform for tracing, evaluating, and monitoring LLM apps

v2.1.322026-07-17PythonApache-2.0
20.8k Open source Free tier Paid