Managing fields in Sanity Studio: grouping and organizing schemas

export default {
  name: 'Foo',
  type: 'document',
  fields: [title, description],
};

// And then have title and description somewhere else:

const title = {
  name: 'title',
  type: 'string',
  validation: (Rule) => Rule.required().error('The title is required.'),
};

const description = {
  name: 'description',
  type: 'text',
  validation: (Rule) => Rule.required().error('The description is required.'),
};

export const string = (name, group) => ({
  name: name,
  type: 'string',
  group: group,
  validation: (Rule) => Rule.required().error(`The ${name} is required.`),
});

export default defineType({
  name: 'article',
  type: 'document',
  groups: [
    {
      name: 'content',
      title: 'Content',
      default: true,
    },
    {
      name: 'seo',
      title: 'SEO',
    },
    {
      name: 'settings',
      title: 'Settings',
    },
  ],
  fields: [...content, ...seo, ...settings],
})

const group = 'content';
const content = [
    defineField({
        name: 'title',
        type: 'string',
        group,
    }),
    defineField({
        name: 'image',
        type: 'image',
        group,
    }),
    defineField({
        name: 'description',
        type: 'text',
        group,
    })
];

export default content;