Opik

Where it runs

• Web
• API

Tags

• #observability
• #evaluation
• #tracing
• #open-source

• View Arize Phoenix details

  ObservabilityFREEMIUMOpen core

  AR

  Arize Phoenix

  Arize AI

  Open-source LLM tracing + evaluation. Strong on retrieval debugging.

  Phoenix is Arize's open-source observability — run locally in a notebook or as a service. Especially strong for inspecting RAG pipelines, finding bad chunks, and tracking retrieval quality over time.

  AI insight: Spins up inside a Jupyter notebook and is sharpest at RAG debugging — finding the bad chunk that poisoned a retrieval.

  • open-source
  • tracing
  • rag
  • retrieval-debugging

  Open
• View Helicone details

  ObservabilityFREEMIUMOpen core

  HE

  Helicone

  Helicone

  Drop-in LLM proxy with logging, caching, and cost tracking.

  One-line integration — change your OpenAI/Anthropic base URL and get a dashboard with every prompt, response, latency, and dollar tracked. Adds caching and rate-limit handling without code changes.

  AI insight: Integrate by changing one base-URL line — no SDK wrapper — and it's open-source, so you can self-host the proxy.

  • proxy
  • logging
  • caching
  • cost-tracking

  Open
• View Langfuse details

  ObservabilityFREEMIUMOpen core

  LA

  Langfuse

  Langfuse

  Open-source LLM observability. Self-hostable, OpenTelemetry-native.

  Tracing, evals, prompt management, and dataset tooling for LLM apps — self-host on your own infra or use Langfuse Cloud. The open-source default when you want full ownership of your observability stack.

  AI insight: The self-hostable, OpenTelemetry-native answer to LangSmith — pick it when observability data has to stay on your own infra.

  • open-source
  • tracing
  • evals
  • self-hosted

  Open
• View LangSmith details

  ObservabilityFREEMIUM

  LA

  LangSmith

  LangChain

  LangChain's hosted observability + eval platform.

  Tracing, dataset management, eval orchestration, and prompt playground from the LangChain team. Pairs naturally if LangChain or LangGraph already runs in your stack, but works standalone via SDKs.

  AI insight: Despite the name it works without LangChain in your stack — but it's cloud-only, where Langfuse lets you self-host.

  • tracing
  • evals
  • datasets
  • langchain

  Open