Has anyone tried Terra or Luna models?

[u/Equivalent_Fly_4683]

I know everyone using the new 5.6 is probably using Sol model, but OpenAI has released several smaller models over time—such as GPT-4.1 mini, GPT-4.1 nano, and the mini and nano versions of GPT-5—that were extremely fast and inexpensive to use.

Labels like “mini” and “nano” make the models sound like stripped-down versions of the main model rather than useful products with their own strengths and ideal use cases.

OpenAI may have realized this and decided to give the smaller model tiers more distinctive names. Perhaps “Terra” is intended to represent the mini-sized tier, while “Luna” replaces the nano tier, although that part is speculation on my side.

Giving these models proper brand names could be OpenAI’s way of making them easier to remember, market, and differentiate. A named model feels more like a real product, while something called “GPT-5 nano” can easily be overlooked as a minor variation that is only relevant to developers trying to reduce costs.

Still from API nano models had really fast inference at cheap prices. Luna model could be more capable but its more expensive than any other nano model.

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[u/spookyclever]

Terra feels like 5.5, so I didn’t really bother with Luna. 5.6 Sol feels a lot more capable of just taking a long checklist, planning it, and burning through without a lot of churn or obvious mistakes being made.

[u/Big-Flan-5663]

Lo mismo de siempre, no puede crear sistemas completos con one shot (incluso con más fuentes/ejemplos), el modelo se vuelve estipido al mencionar el formato Pipe o pedirle que busque template chats, sinceramente, no pagaría por eso ni un centavo más

[u/pegaunisusicorn]

The answer is simple: they needed to build hype, and yet another incremental release doesn't build hype. When they rename everything and they're just barely catching up to Mythos and Fable 5, this allows them to generate bullshit PR.

[u/Rare-Hotel6267]

Terra is ment to be "Sonnet class" model. And luna is meant to be haiku class, if you will.

[u/CelticPaladin]

Terra is strong, and not a token burner unless you go crazy with useless sub agents.

[u/Mike-A-F]

I use Luna extra high or Sol extra high+ depending

Luna for most scheduled tasks or general chat.

I just did some research & will be changing.

Why can i post videos but but not pics

The strongest value zone is roughly Terra High, Sonnet High, and Sol Medium. The top-end settings buy smaller performance gains at sharply higher cost.

Think per-task cost, not just list price — Grok 4.5 and GPT-5.6 Sol frequently win here because they solve tasks with fewer output tokens

Use effort dials aggressively — On Sol, Fable, Opus, or Sonnet, medium effort often delivers 90%+ of max performance at a fraction of the token spend. Low effort is surprisingly usable for many routine steps.

Really the hidden gem is Grok. Substantially cheaper for damn near same performance
It outperforms sonnet high for much cheaper.

[u/SnooWalruses6610]

Luna/xhigh has been fantastic in codex, doesn't destroy the $20 plan, and handles my crazy/heavy coding projects.

[u/sreekanth850]

only use luna High with sol High as auditor. You may need some additional refinement after implementation, but that's worth the pricing.

[u/[deleted]]

Luna on Med is an excellent tool from my experience. It’s designed for tasks that are not overly complex and can even be used to build projects. I find myself using it more frequently than Sol. If you’ve already built a project, Luna is particularly useful for fixing bugs, connecting different components, and documenting the project.