sanity-typed-query.ts

import { defineDocument } from 'sanity-typed-queries';

const { section } = defineDocument(
  'section',
  {
    name: {
      type: 'string',
      title: 'Name',
      validation: (Rule) => Rule.required(),
    },
    pages: {
      title: 'Pages',
      type: 'array',
      of: [{ type: 'reference', to: [{ type: 'page' }] }],
    },
  },
  [page],
);

const { page } = defineDocument(
  'page',
  {
    name: {
      type: 'string',
      title: 'Name',
      validation: (Rule) => Rule.required(),
    },
    pages: {
      title: 'Section',
      type: 'reference',
      to: [{ type: 'section' }],
    },
  },
  [section],
);