<!-- Extension API v0 — pre-1.0. Interfaces may change without notice until P2 seals the custom-code format. First-party extensions track HEAD. -->

# `theme.preset.apply`

Apply one of the active theme's presets (Varyasyon) to the workspace draft — only the values the preset names change.

- **scope**: `design:write`
- **storefront-visible** (bumps the catalog generation): no
- **destructive**: no

## Payload

| field | type | required | notes |
|---|---|---|---|
| `workspace` | string (/^(main\|ws_[A-Z0-9]{26})$/, default "main") | no |  |
| `preset` | string (/^[a-z][a-z0-9-]*$/, ≤40 chars) | yes |  |
| `expectedRev` | integer (1..9007199254740991) \| null | no |  |

### JSON Schema

```json
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "workspace": {
      "default": "main",
      "type": "string",
      "pattern": "^(main|ws_[A-Z0-9]{26})$"
    },
    "preset": {
      "type": "string",
      "maxLength": 40,
      "pattern": "^[a-z][a-z0-9-]*$"
    },
    "expectedRev": {
      "default": null,
      "anyOf": [
        {
          "type": "integer",
          "minimum": 1,
          "maximum": 9007199254740991
        },
        {
          "type": "null"
        }
      ]
    }
  },
  "required": [
    "preset"
  ],
  "additionalProperties": false
}
```