OpenObserve is an open-source observability platform for logs, metrics, traces, and LLM apps, priced per GB with no seat or host fees.
Phoenix is an open-source LLM observability and evaluation platform from Arize AI. It supports OpenTelemetry-based tracing across LLM and agent applications, with built-in evaluators, dataset management, and prompt playgrounds. Phoenix can be self-hosted with Docker or run via the Arize-hosted cloud version.
Core capabilities each platform advertises.
OpenObserveWhat each tool does well, and the limitations to keep in mind.
OpenObservePros
Cons
Pros
Cons
Choose OpenObserve if you wantChoose if you want
Choose Phoenix if you wantChoose if you want
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 1,000+ models through one gateway.
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