Arize AX vs Evidently AI

Arize AX is a platform for improving AI agents by turning production behavior into investigations, evaluations, and experiments. Signal surfaces important issues, helps identify causes, and prepares fixes for review. Managed Agents can investigate failing traces, fix repository bugs, automate recurring checks, or be created from scratch. Swarm Observability tracks status and performance across an agent swarm in real time. Agent-as-a-Judge uses telemetry to produce scalable evaluations that can surface unknown failures, while end-to-end experiments help validate changes. Integrations include OpenAI, Anthropic, Google GenAI, Amazon Bedrock, LangChain, LangGraph, LlamaIndex, CrewAI, and Vercel AI SDK; tracing follows OpenInference conventions and OpenTelemetry. AX Free costs nothing and includes 10 Signal issues/month, 25k trace spans/month, 1 GB ingestion/month, and 15-day retention. AX Pro costs $50 a month, with 25 Signal issues/month, 50k trace spans/month, 10 GB ingestion/month, and 30-day retention. Enterprise pricing is custom. Self-hosted deployment keeps observability data, authentication, APIs, and UI within customer infrastructure; air-gapped deployment is available.

Evidently AI evaluates, tests, and monitors LLMs, RAG applications, AI agents, and machine-learning models. Its open-source Python framework is licensed under Apache 2.0 and provides more than 100 evaluation metrics. Automated evaluations measure output quality, safety, and reliability, can run in pipelines, and produce visual reports. The platform includes tracing, storage for application data and evaluation runs, test-dataset management, and dashboards. Teams can generate realistic, edge-case, or adversarial inputs tailored to a use case. Live monitoring tracks quality checks and can surface drift, regressions, and emerging risks. Red-team testing targets jailbreaks, prompt injections, data leaks, harmful content, and prompt leakage. Predictive ML workflows include performance, drift, and data-quality metrics. Evidently Cloud can send alerts to Slack, Discord, and email. Open-source support is through Discord and documentation; Pro includes email support. The Developer plan is free and limited to 10,000 rows per month, 1GB of snapshots, 3 projects, and 2 seats. Pro costs $80 a month, with additional rows and storage charged separately.