Arize AI is the heavy lifter of the observability world, ideal for ML engineering teams who need rigorous math-backed monitoring (like embedding drift) alongside standard LLM traces. Its open-source library, Phoenix, is a fantastic local tool that visualizes vector retrieval in 3D, a feature most competitors lack. However, solo devs or small teams just needing a simple log viewer might find the platform overkill and the retention limits on lower tiers restrictive.
