Invalid configuration for cross-dataset reference

The Studio reports this error when a crossDatasetReference field definition is missing a required property or has an invalid value.

Schema validation reports this error when a crossDatasetReference field definition is missing a required property or has an invalid value. The most common messages are:

• The cross dataset reference type is missing or having an invalid value for the required "to" property. It should be an array of accepted types.
• A cross dataset reference must specify a `dataset`
• Missing required preview config for the referenced type, followed by the type name.

A valid definition needs:

• dataset: Required. The dataset that holds the referenced documents. The name must be lowercase and at least two characters.
• to: Required. An array of accepted types, with at least one entry.
• type: Required on each entry in to. The name of the referenced document type.
• preview: Required on each entry in to. A preview configuration object.
• studioUrl: Optional. If set, a function that takes {id, type} and returns a URL.

This check looks only at the field definition. It doesn't verify API tokens or CORS origins, so neither is the cause of this error.

A minimal valid definition:

import {defineField, defineType} from 'sanity'

export default defineType({
  name: 'article',
  type: 'document',
  fields: [
    defineField({
      name: 'author',
      type: 'crossDatasetReference',
      dataset: 'production',
      to: [
        {
          type: 'author',
          preview: {
            select: {title: 'name', media: 'image'},
          },
        },
      ],
    }),
  ],
})