Arize AX

Arize AX is a platform for improving AI agents by turning production behavior into issues, investigations, evaluations, and experiments. Signal surfaces problems, investigates root causes, and generates fixes for review. Managed Agents can investigate failing traces, fix repository bugs, automate recurring checks, or be built from scratch. Swarm Observability tracks agent-swarm status and performance in real time. Agent-as-a-Judge uses agent telemetry to create scalable evaluations intended to reveal 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 uses 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; that tier offers SaaS or self-hosted deployment and custom volume and retention. Self-hosting keeps observability data, authentication, APIs, and UI within the customer’s infrastructure.

Arize AX combines tracing, evaluations, experiments, and agent-focused investigation workflows. Compare the listed plan limits and deployment options with your needs before choosing a tier.

Arize AX suits teams working to observe, evaluate, and improve AI agents in production. The free plan offers a way to start, while self-hosting is available on Enterprise.

Overview

Arize AX is an AI-agent platform for teams that need to inspect production behavior and improve agents through evaluation and experimentation. It is best suited to teams running agents at meaningful scale, especially swarms; smaller projects may find its monthly issue and data caps restrictive.

Its strongest advantage is connecting trace investigation with evaluation and experiments. Free access makes it possible to start without a subscription, while the $50 monthly Pro tier raises—but does not remove—limits on issues, trace spans, ingestion, and retention.

Key features

Signal surfaces important issues, helps uncover root causes, and generates fixes for review. AX Free allows 10 issues a month and Pro allows 25, so the workflow is useful for focused investigation but may become constrained for teams handling frequent failures.

Managed Agents can investigate failing traces, fix repository bugs, automate recurring checks, or be built from scratch. Swarm Observability tracks status and performance across an agent swarm in real time. Those capabilities make AX relevant to teams operating more than a single agent, though Enterprise is the tier that offers unlimited Signal issues and custom trace and ingestion limits.

Agent-as-a-Judge uses agent telemetry to create scalable evaluations that can surface unknown failures. End-to-end experiments help teams validate agent changes. Together, these tools support a cycle of finding problems, evaluating behavior, and checking changes rather than stopping at trace collection.

AX integrates with OpenAI, Anthropic, Google GenAI, Amazon Bedrock, LangChain, LangGraph, LlamaIndex, CrewAI, and Vercel AI SDK. OpenInference conventions and OpenTelemetry support tracing instrumentation. The platform also supports LLM, agent, and retrieval tracing, evaluations, prompt management, and token-cost tracking.

For organizations with infrastructure or data-residency requirements, Enterprise can run self-hosted, keeping observability data, authentication, APIs, and UI inside customer infrastructure; air-gapped deployment is available. Free and Pro are SaaS-only. The pricing page lists US, EU, or CA data regions across all three tiers. Security certifications and compliance listed by Arize include SOC 2, PCI DSS, ISO/IEC 27001, GDPR, and HIPAA.

Pricing

Free is a sensible starting point for a small workload: it has no user or evaluation cap, but 1 GB of monthly ingestion and 15-day retention limit how much history teams can keep. Pro costs $50 a month and doubles the trace-span allowance, raises ingestion to 10 GB, and doubles retention to 30 days; its 25-issue Signal ceiling remains a consideration. Enterprise fits teams needing self-hosting, dedicated support, or limits tailored to larger workloads, with custom pricing rather than a fixed monthly rate.

Platforms

AX is available through API and web, with self-hosted deployment for Enterprise. Free and Pro use SaaS deployment, so teams that require their observability stack to stay within their own infrastructure need Enterprise.

Who it's for

AX suits teams building or operating AI agents that want tracing, evaluations, cost tracking, and experimentation in one workflow. Its swarm monitoring and managed investigation capabilities are particularly relevant to teams responsible for multiple agents. It is less compelling for teams seeking self-hosting on a low-cost tier or whose trace and issue volumes exceed the Free or Pro caps.

Pros and cons

• Pros: Connects trace investigation, scalable evaluations, and experiments, helping teams move from finding failures to validating changes.
• Pros: Broad provider and framework integrations, plus OpenInference and OpenTelemetry instrumentation conventions, support varied agent stacks.
• Pros: Unlimited users and evaluations on Free and Pro avoid seat and evaluation-count caps as teams get started.
• Cons: Free and Pro cap Signal issues, trace spans, ingestion, and retention, which can limit sustained production use.
• Cons: Self-hosted and air-gapped deployment require Enterprise, so Free and Pro do not suit organizations that must keep the platform inside their infrastructure.

Alternatives

For a free, open-source framework, consider Evidently AI; its Apache 2.0 license and support for API, desktop, Linux, web, and self-hosted platforms may fit teams prioritizing an open-source option.

Fiddler AI is another freemium option, with a free tier that includes real-time guardrails and latency under 80ms. Helicone may suit teams seeking an open-source alternative; its Hobby tier includes 10,000 free requests and 1 GB of storage.

HoneyHive offers a Developer tier with 10,000 monthly events, up to five users, and 30-day retention. Laminar is a freemium alternative whose Free tier includes 1 GB of data, seven-day retention, one project, and one seat.

Langfuse offers 50k monthly units and 30 days of data access on its Hobby tier. LangSmith may fit a single-seat developer workflow: its Developer tier includes up to 5k base traces per month before pay-as-you-go charges.

LangWatch is another freemium option, described as open source under Apache 2.0.

For broader comparisons, browse LLM Observability Tools, AI Agent Observability Tools, Machine Learning Model Monitoring Software, Model Monitoring Software, and AI LLM Observability Tools.

Verdict

Choose Arize AX if your team needs a connected way to trace, investigate, evaluate, and experiment with AI agents, especially across a swarm. Its free tier lowers the barrier to entry and Pro expands data allowances for $50 a month, but self-hosting requires custom-priced Enterprise and lower tiers retain firm volume limits. Teams needing private deployment or substantially higher capacity should look elsewhere unless Enterprise fits their budget.