A agentindex
Comparison

Arize Phoenix vs Lunary

A like-for-like, spec-level comparison. Both entries are verified against their docs and repo.

Arize Phoenix

Open-source LLM tracing and eval.

  • + Open source with OTel foundations
  • + Good LLM-as-a-judge evals built in
  • − Elastic license restricts some hosted offerings
  • − Enterprise features in the paid Arize cloud

Lunary

Open-source LLM observability and prompt management.

  • + Lightweight and self-hostable
  • + Clean prompt-management UI
  • − Smaller community
  • − Eval features basic
Spec Arize Phoenix Lunary
Role Observability Observability
Tags observability, evaluation, persona-data-scientist, persona-platform-engineer observability, prompt-management, persona-platform-engineer
License Elastic-2.0 Apache-2.0
Open source Yes Yes
Self-hostable Yes Yes
MCP support No No
Pricing free freemium
Price Free tier Free tier
Usage cost No model cost No model cost
Models multi multi
Languages python, typescript typescript
GitHub stars 10.4k —
Last activity 2026-07-04 —