Arize Phoenix vs Noveum AI: is observing your agents enough, or do you need them tested and fixed?

An honest comparison of tracing and visibility versus automated evaluation, voice quality scoring, synthetic testing, and auto-remediation, for AI teams deciding what they actually need.

Noveum

Best for automated eval, voice quality scoring, pre-production synthetic testing, and teams that want actionable fixes.

Arize Phoenix

Best for open-source, self-hosted observability and for teams that need wide framework coverage with zero vendor lock-in.

Which tool is right for you?

Noveum

Noveum tells you what to do next. Arize only shows you what happened.

Noveum is built for teams running agents in production who need more than a trace to look at. You connect your stack, and Noveum scores every output automatically using 100+ built-in scorers, runs NovaSynth synthetic sessions to catch issues before real users hit them, pinpoints root causes, and hands your engineers a structured fix report ready to use in their IDE. No manual review queues. No annotation sprints. No debugging sessions that stretch into days.

Features
Noveum
Arize Phoenix
Built-in evaluation scorers
Yes, 100+
Limited
Automated root cause analysis
Limited
Fix recommendation reports
Limited
Voice pipeline quality scoring
Limited
Synthetic testing
Enterprise-ready custom scorers
Credit-based pricing
Open-source self-hosting
On-prem deployment

From observability to shipped fix: where Arize Phoenix and Noveum split

1

Connect your LLM app

Noveum Advantage

Context manager, under 15 minutes

Install noveum-trace, drop in your API key, and wrap your LLM calls with the context manager. Works with OpenAI, LangChain, LangGraph, CrewAI, and LiveKit. Python and TypeScript SDKs both supported. Your first scored traces appear in the dashboard right away.

Arize Phoenix

OpenTelemetry auto-instrumentation

Drop in auto-instrumentation across your LLM framework of choice. If you already run OpenTelemetry, Phoenix slots right in without a new setup.

2

Evaluate output quality

Noveum Advantage

100+ scorers fire on every trace automatically

Hallucination, faithfulness, RAG accuracy, safety, tool-calling accuracy, voice pipeline quality. All 100+ scorers run on every trace from the moment you connect. LLM-as-judge is built in where you need it. Nothing to configure before scores start arriving.

Arize Phoenix

LLM-as-judge evaluation

Evaluators use LLM prompts to score your traces. Flexible and customizable, but each additional LLM call adds latency and cost as your trace volume grows. There are no deterministic built-in scorers in the current product.

3

Test before your users do

Noveum Advantage

NovaSynth: synthetic testing before real users

NovaSynth runs synthetic voice and text sessions against your live agent at scale. You define realistic personas, write test scenarios covering happy paths, edge cases, and adversarial inputs, and NovaSynth runs those conversations through your agent via voice, text, or phone. Every session is automatically scored with voice quality, safety, and telephony scorers. You catch failures before launch, not after.

Arize Phoenix

No pre-production testing capability

Arize gives you detailed visibility into traces from real users, but there is no built-in synthetic testing system. If your voice agent fails on a specific persona type or edge case, you find out when it happens in production. There is no way to run structured pre-production quality tests through the platform.

4

Go from failure to fix

Noveum Advantage

A structured fix report, ready for your IDE

NovaPilot reads the failure patterns, groups them by category, and produces a structured improvement report covering your prompts, tool calls, and pipeline logic. Drop it into Cursor, Claude, or your IDE and start implementing without a separate debugging session.

Arize Phoenix

No built-in path from failure to fix

Arize gives you full visibility into what failed and where. Your engineers review the dashboard, open a ticket, and own the full loop from spotting the issue to shipping the change. There is no automated remediation agent in the current product.

Evaluation, voice testing, auto-remediation: three things Arize leaves your team to figure out

Noveum evaluation scores dashboard

You should not pay more just because your agents got busy.

Noveum uses NovaEval with 100+ deterministic scorers, complemented by LLM-as-judge where deeper reasoning is needed. Deterministic scorers return the same result every time and cost less to run. Arize relies on LLM-as-judge prompts, so every scorer is an LLM call. At 10,000 traces a day, that adds up fast and results get less consistent as volume grows.

Noveum voice quality scoring

Test your voice agent before your users ever hear it.

Noveum's voice scorers cover TTS quality, response latency, mispronunciation, interruption detection, and tone consistency. And NovaSynth takes it further. You define realistic personas, write test scenarios, and NovaSynth runs those conversations through your live agent via voice or phone at scale. Every session is automatically scored. You find the failures before your users do.

NovaPilot improvement report

Your next bug comes with its own fix attached.

When Noveum detects a failure pattern it categorizes the root cause, analyzes the affected prompts and tool configurations, and produces a structured improvement document ready to use in your IDE. You go from something broke to here is what to change, without a debugging session in between.

Pricing at a glance

Noveum

Predictable credit-based billing

Free$0
Starter$69/mo
Growth$99/mo
EnterpriseCustom
Arize Phoenix

Open source or fully managed cloud

Phoenix OSSFree, self-hosted
AX FreeFree, 25K spans/mo
AX Pro$50/mo
AX EnterpriseCustom

The eval stack your team never has to build

Noveum charges by credit. You pay for evaluation and testing work, not team size or span volume. You get 100+ built-in scorers, voice pipeline scoring, NovaSynth synthetic testing, root cause analysis, and automated fix reports all included from the first paid plan. Arize AX Pro is $50 per month with unlimited users, which is a reasonable entry point. As you move into AX Enterprise, pricing is custom and typically runs $50,000 or more per year at scale. For teams shipping voice agents and AI products at scale, Noveum's model stays predictable as you grow.

Common questions

Our take

Noveum is built for teams that need more than a trace to look at. You get 100+ scorers running on every output from day one, NovaSynth catching voice and agent failures before real users hit them, root cause analysis that tells you exactly why something broke, and automated fix reports your engineers can take straight into their IDE. Less time in logs. More time shipping better agents.

Arize Phoenix is a strong tracing tool. If your team self-hosts, needs zero vendor lock-in, and wants observability across many frameworks, it earns its place.

But observability alone does not close the loop. Knowing what happened is not the same as knowing what broke. And knowing what broke is not the same as knowing how to fix it. If you ship voice agents or need the full eval and remediation loop running automatically, Noveum is the platform that gets you there.

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