Directory · Observability
Arize AI
AI observability and evaluation platform for production LLM and ML systems; maker of the open-source Phoenix library.
Best for
Enterprise-scale monitoring, tracing, and evals of deployed AI systems
More observability tools
Braintrust
Observability · Braintrust · United States
AI evaluation and observability platform — traces feed directly into eval datasets, regression tests, and prompt experiments.
Best for
Eval-first teams, prompt A/B testing, quality loops tied to production traces
Pros
- Traces to evals in one product
- Strong experiment and scoring UX
- Good for PM + eng collaboration
Cons
- Not self-hostable (managed only)
- Pricier at scale than OSS Langfuse
- Less infra-flexible than OpenTelemetry
Alternatives
Giskard
Observability · Giskard · France
Open-source testing framework from a French startup that scans LLM apps and ML models for bias, errors, and vulnerabilities.
Best for
Automated evaluation and red-teaming of LLM applications before release
Helicone
Observability · Helicone · United States
Open-source LLM observability platform offering proxy-based logging, cost tracking, caching, and prompt experiments.
Best for
One-line logging and cost monitoring for LLM API calls