Opik
Evaluation & observability · Open source
About
Comet's open-source platform for logging, evaluating and monitoring LLM apps, including prompt optimisation.
Key features
- Tracing and logging
- LLM-as-judge metrics
- Prompt library
- Agent optimiser
Best for
- — Open-source tracing and evals
- — Automated prompt optimisation
- Pricing
- Open source
- Platforms
- Web, Self-hosted, API
- Works with
- LangChain, OpenAI
- Last checked
- 2026-10-29
- Status
- Listed, not yet tested
Our take
Generous open-source feature set. Younger than some rivals, so expect rough edges.
Features and pricing change often — confirm on comet.com before you commit.
Alternatives to Opik
| Tool | Type | Pricing | Best for |
|---|---|---|---|
| Opik (this) | Evaluation & observability | Open source | Open-source tracing and evals |
| Langfuse | Evaluation & observability | Open source | Tracing LLM apps in production |
| LangSmith | Evaluation & observability | Freemium | LangChain and LangGraph users |
| Braintrust | Evaluation & observability | Freemium | Systematic evals before shipping |
| Arize Phoenix | Evaluation & observability | Open source | Local debugging of LLM traces |
| W&B Weave | Evaluation & observability | Freemium | Teams already on Weights & Biases |
| Helicone | Evaluation & observability | Freemium | Quick cost and usage visibility |