Writer API

if ('Writer' in self) {
  // The Writer API is supported.
}

const writer = await Writer.create({
  monitor(m) {
    m.addEventListener("downloadprogress", e => {
      console.log(`Downloaded ${e.loaded * 100}%`);
    });
  }
});

const options = {
  sharedContext: 'This is an email to acquaintances about an upcoming event.',
  tone: 'casual',
  format: 'plain-text',
  length: 'medium',
};

const available = await Writer.availability();
let writer;
if (available === 'unavailable') {
  // The Writer API isn't usable.
  return;
}
if (available === 'available') {
  // The Writer API can be used immediately .
  writer = await Writer.create(options);
} else {
  // The Writer can be used after the model is downloaded.
  writer = await Writer.create(options);
  writer.addEventListener('downloadprogress', (e) => {
    console.log(e.loaded, e.total);
  });
}

// Non-streaming
const writer = await Writer.create();
const result = await writer.write(
  "An inquiry to my bank about how to enable wire transfers on my account.", {
    context: "I'm a longstanding customer",
  },
);

// Streaming
const writer = await Writer.create();
const stream = writer.writeStreaming(
  "An inquiry to my bank about how to enable wire transfers on my account.", {
    context: "I'm a longstanding customer",
  },
);
for await (const chunk of stream) {
  composeTextbox.append(chunk);
}

// Shared context and per writing task context
const writer = await Writer.create({
sharedContext: "This is for publishing on [popular website name], a business and employment-focused social media platform."
});

const stream = writer.writeStreaming(
  "Write a blog post about how I love all this work on gen AI at Google!" +
  "Mention that there's so much to learn and so many new things I can do!",
  { context: " The request comes from someone working at a startup providing an e-commerce CMS solution."}
);

for await (const chunk of stream) {
  composeTextbox.append(chunk);
}

// Reuse a writer
const writer = await Writer.create({ tone: "formal" });

const reviews = await Promise.all(
  Array.from(
    document.querySelectorAll("#reviews > .review"),
    (reviewEl) => writer.write(reviewEl.textContent)
  ),
);

// Aborting a writer
const controller = new AbortController();
stopButton.onclick = () => controller.abort();

const writer = await Writer.create({ signal: controller.signal });
await writer.write(reviewEl.textContent, { signal: controller.signal });

// Destroying a writer
writer.destroy();