M
Mastraā€¢3w ago
Nic

Re-generate a message

Hi, I am trying to implement a regeneration mechanism. The user should be able to re-generate any message from the history. Right now, I am deleting the message to regenerate + all messages after that one but for some reason, this query always returns all messages: 
const messages = await memory.query({
  threadId: chat.threadId,
  resourceId: chat.resourceId,
  selectBy: {
    include: [
      {
        id: messageId,
        threadId: chat.threadId,
        withPreviousMessages: 1,
        withNextMessages: 1000,
      },
    ],
  },
});
const messages = await memory.query({
  threadId: chat.threadId,
  resourceId: chat.resourceId,
  selectBy: {
    include: [
      {
        id: messageId,
        threadId: chat.threadId,
        withPreviousMessages: 1,
        withNextMessages: 1000,
      },
    ],
  },
});
3 Replies
Mastra Triager
Mastra Triagerā€¢3w ago
šŸ“ Created GitHub issue: https://github.com/mastra-ai/mastra/issues/10276 šŸ” If you're experiencing an error, please provide a minimal reproducible example to help us resolve it quickly. šŸ™ Thank you @Nic for helping us improve Mastra!
Abhi Aiyer
Abhi Aiyerā€¢3w ago
Thanks for reporting this! We have a new query format in 1.0.0-beta that fixes quirks here. But let me see if we can have a fix in the 0.x version
į²¼
į²¼ā€¢3w ago
My solution: 
// actions.ts
const agent = mastra.getAgent("myAgent");
export async function deleteLastMessage(chatId: string) {
  const supabase = createClient();
  const { data: userData } = await supabase.auth.getUser();
  if (!userData?.user) return;
  const memory = await agent.getMemory();
  const { uiMessages } = await memory!.query({
    threadId: chatId,
    resourceId: userData?.user?.id,
  });
  if (uiMessages.length > 0) {
    const lastMessage = uiMessages[uiMessages.length - 1];
    if (!lastMessage) return;
    await memory?.deleteMessages([lastMessage.id]);
  }
}

// client.tsx
import {deleteLastMessage} from 'actions.ts';
//...
  const handleRegenerate = async () => {// Call when regenerate is pressed
    if (status === 'ready' && chatId) {
      await deleteLastMessage(chatId);
      await regenerate();// from useChat
    }
  };
// actions.ts
const agent = mastra.getAgent("myAgent");
export async function deleteLastMessage(chatId: string) {
  const supabase = createClient();
  const { data: userData } = await supabase.auth.getUser();
  if (!userData?.user) return;
  const memory = await agent.getMemory();
  const { uiMessages } = await memory!.query({
    threadId: chatId,
    resourceId: userData?.user?.id,
  });
  if (uiMessages.length > 0) {
    const lastMessage = uiMessages[uiMessages.length - 1];
    if (!lastMessage) return;
    await memory?.deleteMessages([lastMessage.id]);
  }
}

// client.tsx
import {deleteLastMessage} from 'actions.ts';
//...
  const handleRegenerate = async () => {// Call when regenerate is pressed
    if (status === 'ready' && chatId) {
      await deleteLastMessage(chatId);
      await regenerate();// from useChat
    }
  };
Only works for regenerating the last message. You could probably update it to work for regenerating any message but I wouldn't suggest that without also implementing history trees.

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