| Name | Type | Description | Notes |
|---|---|---|---|
| card_index | int | Card position. Auto-filled sequentially when omitted. | [optional] |
| type | string | `product` for a product card; media cards use `cta_url` or a quick-reply type. | [optional] |
| header | object | Media cards only, required. Carries the card's image or video. | [optional] |
| body | object | Optional card body text. | [optional] |
| action | object | Product cards: `{ catalog_id, product_retailer_id }` (required). Media cards: the card's button action (e.g. `cta_url` with `parameters.display_text` and `parameters.url`). | [optional] |