Best Open-source LLM Evaluation & Observability tools

Coze Loop

Full‑life‑cycle platform for building, testing, and monitoring AI agents

Agenta

Accelerate production LLM apps with integrated prompt, evaluation, observability

Laminar

Trace, evaluate, and scale AI applications with minimal code.

Langfuse

Collaborative platform for building, monitoring, and debugging LLM applications.

Phoenix

AI observability platform for tracing, evaluation, and prompt management

OpenLLMetry

Full‑stack observability for LLM applications via OpenTelemetry

TruLens

Systematically evaluate, track, and improve your LLM applications

Opik

Open-source platform for tracing, evaluating, and optimizing LLM applications

OpenLIT

Unified observability and management platform for LLM applications

Helicone

Open-source LLM observability and developer platform for AI applications

Evidently

Evaluate, test, and monitor ML & LLM systems effortlessly

Langtrace

Observability platform for LLM applications with real‑time tracing