Mental Model

ToonUI is a contract between your model and your app.

server teaches -> model describes -> client renders -> app decides

It is not an alternative to JSON renderers like json-render.dev. ToonUI does not try to turn arbitrary JSON into a screen. It teaches the model a small semantic language, validates that language against your active catalog, and lets your app render known components.

Ownership

Important rule

The model does not create new components.

It can only emit standard ToonUI components enabled in the active catalog.

createToonProtocol({
  components: ['text', 'card', 'button'],
});

That prompt will not teach form, table, or chart unless you enable them.

Interactions are intent, not execution

A button like this:

button primary "Delete" reply="delete product 123"

is not a deletion.

It is user intent. Your app decides whether to call a tool, ask for confirmation, check permissions, or ignore it.