Streaming

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import { OpenRouter } from '@openrouter/sdk';
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const openrouter = new OpenRouter({
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  apiKey: process.env.OPENROUTER_API_KEY,
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});
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const result = openrouter.callModel({
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  model: 'openai/gpt-5-nano',
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  input: 'Write a short poem about the ocean.',
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});
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for await (const delta of result.getTextStream()) {
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  process.stdout.write(delta);
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}

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const result = openrouter.callModel({
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  model: 'openai/o1-preview',
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  input: 'Solve this step by step: If x + 5 = 12, what is x?',
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});
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console.log('Reasoning:');
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for await (const delta of result.getReasoningStream()) {
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  process.stdout.write(delta);
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}
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console.log('\n\nFinal answer:');
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const text = await result.getText();
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console.log(text);

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const result = openrouter.callModel({
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  model: 'openai/gpt-5-nano',
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  input: 'Hello!',
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  tools: [myTool],
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});
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for await (const message of result.getNewMessagesStream()) {
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  if (message.type === 'message') {
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    console.log('Assistant message:', message.content);
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  } else if (message.type === 'function_call_output') {
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    console.log('Tool result:', message.output);
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  }
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}

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const result = openrouter.callModel({
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  model: 'openai/gpt-5-nano',
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  input: 'Search for documents',
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  tools: [searchTool], // Generator tool with eventSchema
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});
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for await (const event of result.getFullResponsesStream()) {
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  switch (event.type) {
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    case 'response.output_text.delta':
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      process.stdout.write(event.delta);
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      break;
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    case 'response.function_call_arguments.delta':
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      console.log('Tool argument delta:', event.delta);
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      break;
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    case 'response.completed':
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      console.log('Response complete');
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      break;
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    case 'tool.preliminary_result':
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      // From generator tools
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      console.log('Progress:', event.result);
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      break;
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  }
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}

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const result = openrouter.callModel({
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  model: 'openai/gpt-5-nano',
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  input: 'What is the weather in Paris and Tokyo?',
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  tools: [weatherTool],
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  maxToolRounds: 0, // Don't auto-execute, just get tool calls
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});
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for await (const toolCall of result.getToolCallsStream()) {
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  console.log(`Tool: ${toolCall.name}`);
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  console.log(`Arguments:`, toolCall.arguments);
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  console.log(`ID: ${toolCall.id}`);
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}

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const result = openrouter.callModel({
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  model: 'openai/gpt-5-nano',
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  input: 'Search for TypeScript tutorials',
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  tools: [searchTool], // Generator tool
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});
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for await (const event of result.getToolStream()) {
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  if (event.type === 'delta') {
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    // Raw argument deltas
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    process.stdout.write(event.content);
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  } else if (event.type === 'preliminary_result') {
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    // Progress from generator tools
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    console.log(`\nProgress (${event.toolCallId}):`, event.result);
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  }
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}

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const result = openrouter.callModel({
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  model: 'openai/gpt-5-nano',
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  input: 'Write a story.',
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});
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// Start both consumers concurrently
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const [text, response] = await Promise.all([
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  // Consumer 1: Collect text
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  (async () => {
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    let text = '';
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    for await (const delta of result.getTextStream()) {
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      text += delta;
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    }
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    return text;
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  })(),
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  // Consumer 2: Get full response
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  result.getResponse(),
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]);
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console.log('Text length:', text.length);
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console.log('Token usage:', response.usage);

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const result = openrouter.callModel({
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  model: 'openai/gpt-5-nano',
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  input: 'Write a very long essay...',
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});
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// Start streaming
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const streamPromise = (async () => {
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  let charCount = 0;
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  for await (const delta of result.getTextStream()) {
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    process.stdout.write(delta);
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    charCount += delta.length;
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    // Cancel after 500 characters
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    if (charCount > 500) {
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      await result.cancel();
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      break;
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    }
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  }
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})();
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await streamPromise;
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console.log('\nCancelled!');

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import { useState, useEffect } from 'react';
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function ChatResponse({ prompt }: { prompt: string }) {
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  const [text, setText] = useState('');
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  const [isStreaming, setIsStreaming] = useState(true);
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  useEffect(() => {
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    const openrouter = new OpenRouter({ apiKey: API_KEY });
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    const result = openrouter.callModel({
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      model: 'openai/gpt-5-nano',
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      input: prompt,
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    });
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    (async () => {
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      for await (const delta of result.getTextStream()) {
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        setText(prev => prev + delta);
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      }
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      setIsStreaming(false);
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    })();
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    return () => {
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      result.cancel();
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    };
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  }, [prompt]);
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  return (
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    <div>
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      <p>{text}</p>
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      {isStreaming && <span className="cursor">|</span>}
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    </div>
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  );
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}

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import { Hono } from 'hono';
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import { streamSSE } from 'hono/streaming';
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const app = new Hono();
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app.get('/stream', (c) => {
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  return streamSSE(c, async (stream) => {
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    const result = openrouter.callModel({
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      model: 'openai/gpt-5-nano',
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      input: c.req.query('prompt') || 'Hello!',
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    });
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    for await (const delta of result.getTextStream()) {
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      await stream.writeSSE({
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        data: JSON.stringify({ delta }),
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        event: 'delta',
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      });
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    }
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    await stream.writeSSE({
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      data: JSON.stringify({ done: true }),
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      event: 'done',
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    });
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  });
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});