Pick Lunary if
app teams who will pay Team $20/user/month (or self-host the AGPL repo) to open a first Generations table — not Langfuse first unless they want that OSS trace warehouse.
Read the Lunary pageLunary vs Phoenix
Our take
Pick Lunary if you're on a app team who will pay Team $20/user/month (or self-host the AGPL repo) to open a first Generations table — not Langfuse first unless they want that OSS trace warehouse. Pick Phoenix if you're on a agent team who will self-host Phoenix for $0 (uvx arize-phoenix serve) and only open Arize AX when they want a managed cloud.
Best for
Lunary See what the model just did and edit that prompt
Phoenix See why an agent failed and prove a fix
Free plan
Lunary $0 · you bring compute. Existing Free cloud workspaces stay grandfathered; new ones do not start at $0
Phoenix $0 · local / Docker / Kubernetes. You bring compute. Homepage: uvx arize-phoenix serve
Lowest paid
Lunary Team $20/user/mo
Phoenix AX Pro $50/mo
Runs where
Lunary Local or hosted
Phoenix Hosted
Watch out
Lunary New cloud starts at $20/user
Phoenix ELv2, not Apache
Last checked
Lunary 2026-10-27 · lunary.ai/pricing
Phoenix 2026-10-27 · arize.com/pricing
Which one, then?
Pick Phoenix if
agent teams who will self-host Phoenix for $0 (uvx arize-phoenix serve) and only open Arize AX when they want a managed cloud.
Read the Phoenix page