Tutorial: Build an in-app documentation assistant

const extractSources = (parts) => {
  return parts
    ?.filter(p => p.type === 'tool-invocation' && p.toolInvocation?.toolName === 'search')
    .flatMap(p => p.toolInvocation?.result || [])
    .map(source => ({
      url: source.url || source.path,
      title: source.metadata?.title || source.path,
    })) || [];
};

// In your message rendering:
{messages.map((message) => {
  const sources = message.role === 'assistant' ? extractSources(message.parts) : [];
  return (
    <div key={message.id}>
      {/* message content */}
      {sources.length > 0 && (
        <div className="mt-2 text-xs">
          <p className="font-semibold">Sources:</p>
          {sources.map((s, i) => (
            <a key={i} href={s.url} target="_blank" rel="noopener noreferrer" className="text-blue-600">
              {s.title}
            </a>
          ))}
        </div>
      )}
    </div>
  );
})}

import { useState, useEffect } from 'react';

export function AssistantWidget({ domain, docsURL }) {
  const [threadId, setThreadId] = useState(null);
  const [threadKey, setThreadKey] = useState(null);

  useEffect(() => {
    // Retrieve saved thread ID and key from localStorage
    const savedId = localStorage.getItem('assistant-thread-id');
    const savedKey = localStorage.getItem('assistant-thread-key');
    if (savedId && savedKey) {
      setThreadId(savedId);
      setThreadKey(savedKey);
    }
  }, []);

  const { messages, input, handleInputChange, handleSubmit, isLoading } = useChat({
    api: '/api/assistant',
    body: {
      fp: 'anonymous',
      retrievalPageSize: 5,
      ...(threadId && { threadId }),
      ...(threadKey && { threadKey }),
    },
    streamProtocol: 'data',
    sendExtraMessageFields: true,
    fetch: async (url, options) => {
      const response = await fetch(url, options);
      const newThreadId = response.headers.get('x-thread-id');
      const newThreadKey = response.headers.get('x-thread-key');
      if (newThreadId) {
        setThreadId(newThreadId);
        localStorage.setItem('assistant-thread-id', newThreadId);
      }
      if (newThreadKey) {
        setThreadKey(newThreadKey);
        localStorage.setItem('assistant-thread-key', newThreadKey);
      }
      return response;
    },
  });

  // ... rest of component
}

useEffect(() => {
  const handleKeyDown = (e) => {
    // Cmd/Ctrl + Shift + I to toggle widget
    if ((e.metaKey || e.ctrlKey) && e.shiftKey && e.key === 'I') {
      e.preventDefault();
      setIsOpen((prev) => !prev);
    }

    // Enter (when widget is focused) to submit
    if (e.key === 'Enter' && !e.shiftKey && document.activeElement.id === 'assistant-input') {
      e.preventDefault();
      handleSubmit();
    }
  };

  window.addEventListener('keydown', handleKeyDown);
  return () => window.removeEventListener('keydown', handleKeyDown);
}, [handleSubmit]);