NEW
You can now choose which AI model builds your app. The choice applies to the whole project — you don't re-pick it on every message.
This page covers which models exist, how to choose, and the best-practice pattern that works.
> AVAILABLE MODELS
The model picker lists the following models. Brand and model names stay in English across all languages:
Default
RECOMMENDEDThe recommended starting point. Default picks the model automatically and gives the best quality-to-price ratio — you never have to decide yourself.
Claude Opus 5.5
A frontier model for the most complex builds.
Claude Fable 5.1
A frontier model for large, multi-step projects.
Claude Sonnet 5
A balanced model for everyday building.
GPT-6 Astra
A frontier model for ambitious apps.
GPT-6 Sol
A frontier model for large, multi-step projects.
Kimi K3
A fast model for quick questions and small changes.
DeepSeek V4.1 Flash
A fast model for quick questions and small changes.
[START WITH DEFAULT]
> THE BEST-PRACTICE PATTERN
The core pattern is simple: plan and build a whole new app with a frontier model, then switch to a faster, cheaper model for quick questions and small changes.
1. PLAN & BUILD
Plan and build a whole new app with a frontier model.
2. SWITCH
Switch to a faster, cheaper model for quick questions and small changes.
3. RE-PICK ANYTIME
You can re-pick the model at any time — the choice applies to the whole project.
> PRICING — THE PICKER IS THE SOURCE OF TRUTH
The model picker shows each model's price in credits per 1 million tokens (input, output, cache input).
Compare models using the live numbers in the picker — this page does not list concrete prices, because they change.
// The picker is the only source for prices — don't rely on screenshots or old numbers.
> WHO CAN CHANGE THE MODEL
The following people can change the model. The choice is saved for the project on the next message and shared with all collaborators:
| Role | Permission |
|---|---|
| Owner | Can change the model at any time. |
| Collaborators with build access | Can change the model. |
| Assigned team member | Can change the model. |
> WHAT HAPPENS WHEN A MODEL RETIRES
If a model retires, it is marked “No longer available” in the picker.
Your next message falls back to the default model, so your build is never interrupted. You can re-pick the model at any time.
> QUICK START PROMPT
Copy this prompt and paste it into your Caffeine project. It sets the build model for your project:
Set the build model for this project to Default. Then plan and build the whole app with a frontier model, and switch to a faster, cheaper model for quick questions and small changes. Show me the model picker so I can compare prices in credits per 1M tokens.> COLLABORATOR ROLES: COMMENTER VS BUILDER
As of August 11, 2026, collaborators come in two roles. Commenters can view and comment but cannot change the app; Builders can change the app with prompts, just like the owner.
COMMENTER
Can view the app and leave comments, but cannot change it.
BUILDER
Can change the app with prompts, just like the owner.
> THE “REQUEST TO BUILD” FLOW
As of September 23, 2026, a Commenter can request an upgrade to Builder. The owner receives the request and decides whether to grant build access.
The Commenter clicks “Request to build”.
The owner is notified of the request.
The owner approves or declines — on approval the Commenter becomes a Builder.
> COPY A PROJECT TO ANOTHER WORKSPACE
As of August 19, 2026, you can copy a project to another workspace. This is useful when you need to move work between teams or bring a personal project into a shared workspace.
// Builder Model Selection Checklist
- I know I can choose which model builds my app, and the choice applies to the whole project
- I start with Default because it gives the best quality-to-price ratio
- I plan and build new apps with a frontier model, then switch to a faster, cheaper model for small changes
- I use the live prices in the picker as the basis for comparison
- I know a retired model falls back to the default, and I can re-pick at any time
> SUMMARY
You can now choose the model that builds your app. Start with Default, build new apps with a frontier model, and use a faster, cheaper model for small changes.
The picker is the only source for prices, the choice is saved for the project and shared with all collaborators, and you can re-pick at any time.