Back to Lmnr

Alternatives to Lmnr

30 tools that compete with or replace Lmnr. Ranked by direct product-type match — not generic category overlap.

Last updated
Cross-checked through our multi-step verification ·

Why people look for alternatives to Lmnr

The complaints that come up most often in public discussion — reviews, forums and community threads. Not our opinion, and not the vendor's marketing.

  • Limited community and support channels outside GitHub.
  • Setup requires understanding of OTLP and agent architecture.
  • Dashboard customization can be complex for beginners.
  • Some integrations are still in development or incomplete.

Drawn from 51 mentions across 5 sources · researched Jul 15, 2026.

In fairness: users also consistently praise open-source with rust core for high performance, and natural-language signals for easy failure detection. A complaint list is not a verdict — see the full picture on the Lmnr page.

Arize Phoenix

Arize Phoenix

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

FreemiumTry
Visit Arize Phoenix
Phoenix

Phoenix

Open-source LLM observability and agent evaluation you can trace, evaluate, and self-host for free.

FreemiumTry
Visit Phoenix
Langfuse

Langfuse

Open-source LLM observability and agent evals: trace, evaluate, and improve production AI agents with MIT-licensed tooling.

FreemiumTry
Visit Langfuse
Opik (Comet)

Opik (Comet)

Open-source AI observability for agent tracing, LLM-as-a-judge evals, and coding-agent cost tracking.

FreemiumTry
Visit Opik (Comet)
AgentOps

AgentOps

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

FreemiumTry
Visit AgentOps
Dash0

Dash0

Dash0 is OpenTelemetry-native observability where Agent0 investigates incidents, finds root cause, and opens fix PRs.

FreemiumTry
Visit Dash0
MLflow

MLflow

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

FreeTry
Visit MLflow
Agenta

Agenta

Open-source AI coworker workspace that builds, schedules and ships agents to Slack or Telegram

FreemiumTry
Visit Agenta
Maxim AI

Maxim AI

Maxim AI evaluates, simulates and observes AI agents — with Bifrost, its open-source LLM gateway, handling routing, budgets and guardrails.

FreemiumTry
Visit Maxim AI
RAGAS

RAGAS

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

FreeTry
Visit RAGAS
Metoro

Metoro

Metoro is a Kubernetes observability and AI SRE agent that watches your cluster with eBPF and opens fix PRs for production issues.

FreemiumTry
Visit Metoro
OpenLIT

OpenLIT

OpenLIT is an open-source, OpenTelemetry-native agent harness engineering platform for LLM tracing, evals, and guardrails you self-host.

FreemiumTry
Visit OpenLIT
OpenJudge

OpenJudge

OpenJudge is an Apache 2.0 open-source AI evaluation framework shipping 50+ benchmark-validated graders for agents, LLMs, code, math, and multimodal models.

FreeTry
Visit OpenJudge
LangSmith

LangSmith

LangSmith is agent and LLM observability: trace, monitor, and evaluate AI agents in cloud, BYOC, or self-hosted.

FreemiumTry
Visit LangSmith
Lilypad

Lilypad

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

FreeTry
Visit Lilypad
TruLens

TruLens

TruLens traces AI agent runs with OpenTelemetry-native evals, showing where an agent fails and where you can cut cost.

FreeTry
Visit TruLens
Fiddler AI

Fiddler AI

Fiddler AI is an enterprise AI control plane for agent observability, inline guardrails, and auditable AI governance.

FreemiumTry
Visit Fiddler AI
PostHog

PostHog

PostHog is product analytics with session replay, feature flags, error tracking, and a context warehouse for you and your AI agents.

FreemiumTry
Visit PostHog
Evidently AI

Evidently AI

Evidently AI is an open-source Python framework for LLM evaluation, RAG testing, and ML model monitoring under Apache 2.0.

FreemiumTry
Visit Evidently AI
Galileo

Galileo

Galileo is an AI observability and eval engineering platform that turns offline evals into production guardrails for agents and RAG.

FreemiumTry
Visit Galileo
Braintrust

Braintrust

Braintrust is an agent observability platform that traces AI runs, scores quality with evals, and surfaces production failure patterns.

FreemiumTry
Visit Braintrust
Raindrop

Raindrop

Raindrop traces, detects, and simulates fixes for silent AI agent failures in production before they reach your users.

FreemiumTry
Visit Raindrop
Tokentelemetry

Tokentelemetry

Local, MIT-licensed token and cost observability for AI coding agents — reads the logs your agents already write.

FreeTry
Visit Tokentelemetry
Burntop

Burntop

Free open-source AI usage tracking and analytics that syncs your token and cost data from Claude, Cursor, ChatGPT and other tools onto a shareable dashboard.

FreeTry
Visit Burntop
Roark

Roark

Voice AI QA and evals: simulate callers before launch, then score every production call on 500+ audio-native metrics.

FreemiumTry
Visit Roark
PandaProbe

PandaProbe

PandaProbe is open-source agent observability that traces runs, evaluates outcomes, and turns failures into validated fixes via its Repair

FreemiumTry
Visit PandaProbe
Goodfire

Goodfire

Silico is Goodfire's interpretability agent for understanding and debugging the internals of your AI models.

FreemiumTry
Visit Goodfire
Galileo AI Evals

Galileo AI Evals

Galileo AI Evals turns offline evaluations into production guardrails that gate your AI agents in real time.

FreemiumTry
Visit Galileo AI Evals
Comet

Comet

Opik by Comet turns LLM traces into root-cause groupings, eval scores and code fixes so agent teams stop shipping the same bug twice

FreemiumTry
Visit Comet
Confident AI

Confident AI

LLM evaluation, observability, and red teaming in one workspace — ship AI you can actually trust

FreemiumTry
Visit Confident AI

Frequently asked questions

What are the best alternatives to Lmnr?

We currently list 30 alternatives to Lmnr: Arize Phoenix, Phoenix, Langfuse, Opik (Comet), AgentOps. Each is ranked by direct product-type match rather than generic category overlap.

How do you choose which Lmnr alternatives to show?

Alternatives are ranked by direct product-type match — tools that do the same job — not by shared category tags. Every listed tool is independently re-verified on a continuous cycle.