Stream a response

const stream = await client.chat.completions.create({
  model: "gpt-5.4-mini",
  stream: true,
  messages: [
    { role: "system", content: "You are a concise technical writer." },
    { role: "user", content: "Explain database indexes in three paragraphs." },
  ],
});

for await (const chunk of stream) {
  process.stdout.write(chunk.choices[0]?.delta?.content ?? "");
}