Schema type is missing a required property

Every schema type needs both a type and a name property. Studio reports one of these problems when either is missing or has the wrong shape:

• Missing type name — the type has no name property.
• Type is missing a type. — the type has no type property.
• Type has an invalid "type"-property - should be a string. — the type property is set to something that isn't a string.

The type property says which type your schema type builds on — for example a document, an object, or a string. The name is what you use to refer to this type elsewhere in your schema. To add a field that references one of your own types, you refer to it by name:

import {defineType, defineField} from 'sanity'

const author = defineType({
  name: 'author', // the name other types use to refer to this type
  type: 'document',
  fields: [defineField({name: 'name', type: 'string'})],
})

const book = defineType({
  name: 'book',
  type: 'document',
  fields: [
    defineField({name: 'title', type: 'string'}),
    defineField({
      name: 'author',
      type: 'reference',
      to: [{type: 'author'}], // refers to the "author" type by its name
    }),
  ],
})

export const schemaTypes = [author, book]

Studio's schema errors screen names the type each problem belongs to, so start there. Declaring your types with defineType and defineField catches all three problems in your editor, before Studio starts.