Discover fields & options

Ask the API what blocks, theme settings, and custom attributes a collection supports so you can build valid writes without guessing

Every collection's blocks, theme settings, and custom attributes are specific to the tenant and its theme. Rather than hard-coding field names or guessing valid values, ask the API first. Each mutation endpoint has a matching read-only …/schema endpoint that describes exactly what you can write.

The workflow

Discover → create → mutate. Read the schema once, then construct your create/block/settings/attribute writes from it.

The schema endpoints

Endpoint	Describes
`GET /{version}/{tenant}/{collection}/blocks/schema`	The block types available and each block's fields
`GET /{version}/{tenant}/{collection}/theme-settings/schema`	A record's theme settings (for its template)
`GET /{version}/{tenant}/{collection}/custom-attributes/schema`	A collection's custom attributes
`GET /{version}/{tenant}/theme/settings/schema`	The theme's site-wide settings

curl -H "Authorization: users API-Key a1b2c3d4-…" \
  "https://api.basker.app/partners/2026-02/remarkable-theatre/events/custom-attributes/schema"

What a field looks like

Every field comes back in a uniform shape, so one piece of code can handle them all:

{
  "key": "theme_color",        // the name to use in your write
  "type": "select",            // text · richText · number · checkbox · select · date ·
                               // relationship · upload · customObject · array · group
  "label": "Theme Color",
  "options": [                 // present for select / radio: use one of these values
    { "value": "azure", "label": "Azure" },
    { "value": "midnight", "label": "Midnight" }
  ],
  "relationTo": "media",        // present for relationship / upload
  "customObjectType": "genre",  // present for customObject: the type to link
  "hasMany": false,
  "fields": [ /* nested fields, present for array / group */ ]
}

options lists the only valid values for a select/radio: send one of them exactly.
customObjectType tells you which custom-objects a customObject field links to (see below).
fields recurses for array and group types, describing each sub-field.

Building values from the schema

Use the field's type to construct its value:

`type`	Send
`text`, `textarea`, `email`	a string
`richText`	an HTML string (or `<key>_html`)
`number`	a number
`checkbox`	a boolean
`select`, `radio`	one of the field's `options` values
`date`	an ISO 8601 string
`relationship`, `upload`	an id (or an array of ids when `hasMany`)
`customObject`	a custom-object instance id (or an array when `hasMany`)
`array`	a list of objects shaped by the field's nested `fields`
`group`	an object shaped by the field's nested `fields`

Linking custom-objects

A customObject field links to instances of the type named in customObjectType. List the matching instances, then set their id(s):

# the schema said: { "key": "genres", "type": "customObject", "customObjectType": "genre", "hasMany": true }
curl -H "Authorization: users API-Key a1b2c3d4-…" \
  "https://api.basker.app/partners/2026-02/remarkable-theatre/custom-object-instances?where[definition.handle][equals]=genre"
# → pick an id, then: "set": { "genres": ["<instance-id>"] }

Instances may belong to your tenant or, if your tenant is in a tenant group, to another member that shares them. Both are listed and both can be linked. If no instances of that type exist anywhere in scope, the field cannot be linked yet.

Next steps

Edit content blocks: apply the block/theme-settings schema you just read.
Bulk update configured fields: preview and apply one change across matching records.
Field selection: trim what a read returns.