Opik (Comet)

Opik hits a sweet spot that few tools in the observability space target: multi-step agentic workflows. Most alternatives—LangFuse, openllmetry, even Datadog's LLM Observability—are built for single-turn LLM calls or simple chains. Opik, by contrast, is purpose-built to trace the zigzag path a real agent takes: tool call, retrieval, LLM response, repeat. If you're building agents with LangChain, LlamaIndex, or directly on Claude Code/Codex, you'll find the tracing granularity immediately useful. The standout feature is Ollie, the auto-fix harness. It doesn't just log what happened—it suggests and implements fixes directly in your codebase, with version control built in. This is genuinely novel. In practice, it works well for deterministic bugs and assertion violations, but psychedelic hallucination patterns or deep logic errors may still require human intervention. Still, for regression testing and preventing recurring issues, it saves hours. Cost Intelligence is another unique angle. As engineering teams burn real dollars on Claude Code and Codex, Opik gives you a dashboard of per-developer and per-team spend. This is an enterprise pain point that vendors like LangFuse haven't addressed directly. If you're an engineering manager worried about AI cost bloat, this alone justifies a trial. Where Opik falls short: the UI can feel dense—there's a lot of information on screen at once. The learning curve is steeper than simpler alternatives like LangFuse if you just want basic log browsing. And while the open-source core is generous, the enterprise features (SSO, audit trails, compliance) are behind a custom pricing wall. For a startup with no compliance needs, the self-hosted free tier is genuinely usable. In summary: pick Opik if you're building agentic systems and need