> For the complete documentation index, see [llms.txt](https://docs.mapeo.app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mapeo.app/espanol/guia-de-referencia-completa/customization-options/custom-configurations/creating-custom-configurations/codificar-la-configuracion/creating-fields.md).

# Creating details fields

{% hint style="info" %}
To review key information on defining details fields, see [Campos de detalles](/espanol/guia-de-referencia-completa/customization-options/custom-configurations/creating-custom-configurations/planeando-la-configuracion-y-la-estructura-de-datos/campos-de-detalles.md).
{% endhint %}

### In `fields` directory customize the `.json` files

Each `.json` file in the **fields** directory needs a `key`, `type`, `label`, and `placeholder.`

`type` can be one of `select_multiple`, `select_one`, or `text`.

For `select_one` and `select_many` fields, you will need to define an array of answer `options.`

#### Example fields file (`name.json`):

```
{
    "key": "name",
    "type": "text",
    "label": "Name",
    "placeholder": "Common name of this place"
}
```