Overview

Rating

10.0 / 10

Rating

Best For

Developers building multi-agent systems with frameworks like CrewAI, AG2, and the OpenAI Agents SDK who want session-level debugging

Best For

Engineering teams building agent and RAG systems who want OpenTelemetry-native observability with both self-hosted and managed options

Product Summary

AgentOps is an open-source observability SDK for AI agents, with session replay, time-travel debugging, and cost tracking across 400+ LLMs and frameworks.

Product Summary

Phoenix is an open-source LLM observability and evaluation platform from Arize AI. It supports OpenTelemetry-based tracing across LLM and agent applications, with built-in evaluators, dataset management, and prompt playgrounds. Phoenix can be self-hosted with Docker or run via the Arize-hosted cloud version.

Starting Price

Open Source

Free Trial

Free Version

Yes

Free Version

Website

agentops.ai

Website

phoenix.arize.com

Key features

Core capabilities each platform advertises.

AgentOps

Session replay with time-travel debugging
Decorators for sessions, agents, operations, and workflows
Multi-agent interaction graphs
Cost and token tracking across 400+ LLMs

Phoenix

OpenTelemetry-based LLM and agent tracing
Built-in evaluators for hallucination and relevance
Dataset and experiment management
Prompt playgrounds and versioning
Self-hosted Docker deployment or Arize cloud

Strengths and tradeoffs

What each tool does well, and the limitations to keep in mind.

AgentOps

Pros

SDK and dashboard app are both MIT-licensed and self-hostable
Session replay is organized around the full agent run, not single requests
Native integrations with the major agent frameworks, including a built-in CrewAI option

Cons

Evals are limited to custom metrics, with scorecards and an eval playground still on the roadmap
No prompt management or LLM gateway
SSO, SLA, and SOC 2 and HIPAA coverage are Enterprise only
The free tier caps at 5,000 events

Phoenix

Pros

Open-source with active development by Arize
OpenTelemetry-native (no proprietary trace format lock-in)
Strong evaluator library out of the box
Both self-hosted and managed cloud options available
Upgrade path to full Arize enterprise platform

Cons

AgentOps or Phoenix — which should you choose?

Choose AgentOps if you wantChoose if you want

Debugging multi-agent CrewAI and AG2 systems
Replaying a failed agent session step by step
Tracking LLM spend per agent session

Choose Phoenix if you wantChoose if you want

OpenTelemetry-native LLM observability
Hallucination detection for RAG
Experiment tracking and golden-set evaluation
Prompt iteration and comparison
Self-hosted tracing for compliance-sensitive teams

Compare AgentOps and Phoenix on your own traffic

10KFree traces/mo

1,000+Models

5 minSetup

Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 1,000+ models through one gateway.

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AgentOps vs Phoenix (2026)

Overview

Key features

Strengths and tradeoffs

AgentOps or Phoenix — which should you choose?

Compare AgentOps and Phoenix on your own traffic

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