Streaming responses render incrementally in the UI

Configuring streaming at the API level but awaiting the full response on the frontend is a silent no-op: the server dutifully streams tokens into a reader that buffers them all before a single setState call, producing the exact frozen-UI experience that streaming was supposed to eliminate. This bug pattern is extremely common when developers half-migrate from non-streaming to streaming and forget to update the consuming hook or component state logic.

In your chat hook at src/hooks/useChat.ts, read the response body with getReader() and update message state on every decoded chunk inside the loop rather than after it completes. Strongly prefer the Vercel AI SDK's useChat, which handles incremental state correctly by default.

const reader = response.body.getReader();
const decoder = new TextDecoder();
while (true) {
  const { done, value } = await reader.read();
  if (done) break;
  setMessage(prev => prev + decoder.decode(value));
}