## Example

```json
{
  "aiInstructions": {
    "generateLearnedAbilities": {
      "custom": "## Learnable Abilities\nThis world admits four families: arcane spells, martial disciplines, crafting techniques, and social arts. Each requires a teacher, an apprenticeship arc, or a moment of revelation. Avoid raw 'X gains ability Y' jumps."
    }
  }
}
```

## Fields

### custom

The only key — free-form rules for what is learnable in this world and how it is acquired.

## Authoring pattern

Cover in `custom`:

- What families of abilities exist in this world (magical schools, martial techniques, social arts, crafting trades).
- The rough boundary between learnable and impossible — what the world's logic rules out.
- How abilities are typically acquired: teachers, training arcs, moments of revelation, finding ancient texts.