# Exposed Surface

Nothing is exposed by accident.

## Opt-In Rules

- A model only becomes queryable once it opts in via `toolConfig()` and `allowRead()`.
- Relations are only available when you configure them explicitly, and only with a description:

```php
->relations([
    'author' => 'The author who wrote the article.',
])
```

A relation method existing on the model is not enough by itself. It has to be listed here to be exposed at all.

There is no way to add a relation without a description either. The description is the text the AI is shown for that relation in `with` and `withAggregate`, so an undescribed relation is simply invisible rather than present but unexplained.

## Columns

The current runtime column set comes from the model schema snapshot, not from the field-description map alone.

- database columns are discovered from the table at runtime
- `visible` and `hidden` decide which columns stay exposed
- casts refine the detected data types
- enum columns contribute known enum values for validation hints

Field descriptions still matter, but today they are descriptive metadata, not the hard allowlist.

## Relation Rules

- Nested eager-loading paths are derived from the frozen configs of related models.
- Nested relation paths are limited by `relationPathMaxDepth`.
- Root model scopes are always applied to the main query.
- Related model scopes are applied when a configured relation is eager-loaded.
- Direct relation aggregates also respect the related model's configured scopes.
- Relation aggregates are supported for direct configured relations only.
- Dotted relation-path columns are supported only for relation kinds that can be translated into auto-derived join paths.

## Supported Query Shape Today

- `explain`
- `expressions`
- `select`
- `distinct`
- `where`
- `groupBy`
- `orderBy`
- `limit`
- `offset`
- `with`
- `withAggregate`