async function generate() {
  'use server';
  const streamable = createStreamableValue('');

  streamable.append('Hello');
  streamable.append(' ');
  streamable.append('World');
  streamable.done();

  return streamable.value;
}

import { readStreamableValue } from '@ai-sdk/rsc';

export default function Page() {
  const [generation, setGeneration] = useState('');

  return (
    <div>
      <button
        onClick={async () => {
          const stream = await generate();

          for await (const value of readStreamableValue(stream)) {
            setGeneration(value);
          }
        }}
      >
        Generate
      </button>
    </div>
  );
}