Alternatives to Comet

Arize Phoenix is open-source LLM observability: trace every agent step, run evals, and self-host your traces.

Trace, evaluate, and iterate AI agents with Phoenix — open-source LLM observability you can self-host.

Open-source LLM observability, prompt management, and evaluation for teams running AI agents in production.

Open-source LLM observability, prompt management, and agent evals in one MIT-licensed platform.

Metoro is a Kubernetes-native observability platform whose eBPF collector feeds an AI SRE agent that detects, root-causes, and opens fix pull requests for

OpenJudge is an open-source AI evaluation framework with 50+ production-grade graders for agents, multimodal models, code, and math.

Open-source, OpenTelemetry-native evaluation and tracing that shows exactly where your AI agent fails — and where you can cut cost.

Open source AI engineering platform for agent and LLM tracing, evaluation, prompt management, and ML lifecycle work.

Open-source workspace for building, evaluating, and deploying AI agents you talk to in Slack, Telegram, or a browser chat

Maxim AI simulates, evaluates, and observes AI agents in one workspace, with an open-source gateway (Bifrost) for routing and governance.

Open Interpreter is an open-source terminal agent that turns plain-English requests into real file edits and shell commands on your machine.

Open-source Python framework that replaces vibe checks with reproducible evaluation loops for RAG pipelines and AI agents.

Open-source Python framework for evaluating and monitoring LLMs, RAG apps, AI agents, and predictive ML models.

AI observability and eval engineering platform that turns offline evals into live production guardrails for agents and RAG systems.

Open-source agent tracing, LLM-as-a-judge evals, and coding-agent cost tracking you can self-host.

Developer observability platform that traces, replays, and debugs AI agent runs across OpenAI, CrewAI, Autogen and 400+ LLMs

Agent observability that traces every AI run, scores quality with evals, and surfaces production patterns you didn't know to look for.

Raindrop is agent observability that finds silent failures in production AI agents, investigates the root cause, and simulates the fix before you merge.

Open-source, OpenTelemetry-native observability for AI agents that catches failures automatically and helps you fix them.

Agent and LLM observability from the LangChain team: trace, monitor, and evaluate agents in production, cloud, BYOC, or self-hosted.

AI observability and eval-engineering platform that turns offline evals into live production guardrails.

Open-source LLM observability, evaluation, and cost tracking for teams shipping agentic AI, from Comet.

Open-source, OpenTelemetry-native platform for LLM tracing, evaluation, prompt management, guardrails, and GPU monitoring you host yourself.

OpenTelemetry-native observability with an AI SRE that investigates incidents and opens fix PRs.

Open-source LLM observability, agent simulation testing and evaluation for teams shipping agentic AI.

Open-source OpenTelemetry tracing, versioning, and sessions for Python LLM apps—bring your own backend.

Discontinued: WhyLabs ceased operations in 2025 and open-sourced its platform; whylogs and langkit live on as open source.

Fiddler AI is an enterprise AI control plane for agent observability, guardrails, and governance across the agentic lifecycle.

OpenCompass (司南) benchmarks LLMs, VLMs, and AI4S models against 100+ open evaluation datasets with published, dated leaderboards

Local, MIT-licensed token and cost observability for AI coding agents — no SDK, no signup, nothing leaves your machine.