convex-agents-streaming

await thread.streamText(
  { prompt },
  {
    saveStreamDeltas: {
      chunking: "line", // "word" | "line" | regex | function
      throttleMs: 500, // Save deltas every 500ms
    },
  }
);

import { vStreamArgs, syncStreams } from "@convex-dev/agent";
 
export const listMessagesWithStreams = query({
  args: {
    threadId: v.string(),
    paginationOpts: paginationOptsValidator,
    streamArgs: vStreamArgs,
  },
  handler: async (ctx, { threadId, paginationOpts, streamArgs }) => {
    const messages = await listUIMessages(ctx, components.agent, {
      threadId,
      paginationOpts,
    });
 
    const streams = await syncStreams(ctx, components.agent, {
      threadId,
      streamArgs,
    });
 
    return { ...messages, streams };
  },
});

import { useUIMessages, useSmoothText } from "@convex-dev/agent/react";
 
function ChatStreaming({ threadId }: { threadId: string }) {
  const { results } = useUIMessages(
    api.streaming.listMessages,
    { threadId },
    { initialNumItems: 20, stream: true }
  );
 
  return (
    <div>
      {results?.map((message) => (
        <StreamingMessage key={message.key} message={message} />
      ))}
    </div>
  );
}
 
function StreamingMessage({ message }: { message: UIMessage }) {
  const [visibleText] = useSmoothText(message.text, {
    startStreaming: message.status === "streaming",
  });
 
  return <div>{visibleText}</div>;
}