await index.upsert({
  id: "star-wars",
  content: { title: "Star Wars", genre: "sci-fi" },
  metadata: { year: 1977 }
});

await index.upsert([
  {
    id: "inception",
    content: { title: "Inception", genre: "action" }
    metadata: {
      year: 2010,
    },
  },
  { ... },
]);

await index.upsert({
  id: "star-wars",
  content: {
    title: "Star Wars: Episode IV - A New Hope",
    genre: "sci-fi"
  },
});