Lifecycle hooks

export const myChat = chat.agent({
  id: "my-chat",
  clientDataSchema: z.object({ userId: z.string() }),
  onBoot: async ({ chatId, clientData, continuation, previousRunId }) => {
    const user = await db.user.findUnique({ where: { id: clientData.userId } });
    userContext.init({ name: user.name, plan: user.plan });

    if (continuation) {
      // Re-hydrate per-chat in-memory state from your DB.
      // `previousRunId` is the public id of the prior run (use it for
      // logging or to look up persisted state keyed on run id).
      const saved = await db.chatState.findUnique({ where: { chatId } });
      if (saved) {
        // Re-apply your saved per-chat state into wherever your
        // run() reads it from (a chat.local slot, an in-memory map, etc.).
        userContext.applySaved(saved);
      }
    }
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  onRecoveryBoot: async ({ partialAssistant, inFlightUsers, writer, cause, previousRunId }) => {
    writer.write({
      type: "data-chat-recovery",
      data: { cause, previousRunId, partialPresent: partialAssistant !== undefined },
      transient: true,
    });
    // Return nothing → fall through to the smart default
    // (splice partial + first user into chain, dispatch the rest).
  },
  run: async ({ messages, signal }) =>
    streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal }),
});

export const myChat = chat.agent({
  id: "my-chat",
  clientDataSchema: z.object({ userId: z.string() }),
  onBoot: async ({ clientData }) => {
    // Per-process state — runs on every fresh worker (initial,
    // preloaded, continuation). See onBoot above.
    const user = await db.user.findUnique({ where: { id: clientData.userId } });
    userContext.init({ name: user.name, plan: user.plan });
  },
  onPreload: async ({ chatId, clientData, runId, chatAccessToken }) => {
    // Chat-scoped DB rows — only matters on preload (and onChatStart as
    // a fallback when not preloaded).
    await db.chat.create({ data: { id: chatId, userId: clientData.userId } });
    await db.chatSession.upsert({
      where: { id: chatId },
      create: { id: chatId, runId, publicAccessToken: chatAccessToken },
      update: { runId, publicAccessToken: chatAccessToken },
    });
  },
  onChatStart: async ({ preloaded }) => {
    if (preloaded) return; // Already initialized in onPreload
    // ... non-preloaded chat-row initialization
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  onChatStart: async ({ chatId, clientData, preloaded }) => {
    if (preloaded) return; // Already set up in onPreload

    const { userId } = clientData as { userId: string };
    await db.chat.create({
      data: { id: chatId, userId, title: "New chat" },
    });
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

import { validateUIMessages } from "ai";

export const myChat = chat.agent({
  id: "my-chat",
  onValidateMessages: async ({ messages }) => {
    return validateUIMessages({ messages, tools: chatTools });
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, tools: chatTools, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  hydrateMessages: async ({ chatId, trigger, incomingMessages }) => {
    const record = await db.chat.findUnique({ where: { id: chatId } });
    const stored = record?.messages ?? [];

    // Append the new user message and persist
    if (trigger === "submit-message" && incomingMessages.length > 0) {
      const newMsg = incomingMessages[incomingMessages.length - 1]!;
      stored.push(newMsg);
      await db.chat.update({
        where: { id: chatId },
        data: { messages: stored },
      });
    }

    return stored;
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  onTurnStart: async ({ chatId, uiMessages, runId, chatAccessToken }) => {
    await db.chat.update({
      where: { id: chatId },
      data: { messages: uiMessages },
    });
    await db.chatSession.upsert({
      where: { id: chatId },
      create: { id: chatId, runId, publicAccessToken: chatAccessToken },
      update: { runId, publicAccessToken: chatAccessToken },
    });
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  onBeforeTurnComplete: async ({ writer, usage, uiMessages }) => {
    // Write a custom data part while the stream is still open
    writer.write({
      type: "data-usage-summary",
      data: {
        tokens: usage?.totalTokens,
        messageCount: uiMessages.length,
      },
    });

    // You can also compact messages here and write progress
    if (usage?.totalTokens && usage.totalTokens > 50_000) {
      writer.write({ type: "data-compaction", data: { status: "compacting" } });
      chat.setMessages(compactedMessages);
      writer.write({ type: "data-compaction", data: { status: "complete" } });
    }
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  onTurnComplete: async ({ chatId, uiMessages, runId, chatAccessToken, lastEventId }) => {
    // Atomic write — see Database persistence for the race-condition rationale
    await db.$transaction([
      db.chat.update({
        where: { id: chatId },
        data: { messages: uiMessages },
      }),
      db.chatSession.upsert({
        where: { id: chatId },
        create: { id: chatId, runId, publicAccessToken: chatAccessToken, lastEventId },
        update: { runId, publicAccessToken: chatAccessToken, lastEventId },
      }),
    ]);
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  onChatSuspend: async (event) => {
    // Tear down expensive resources before suspending
    await disposeCodeSandbox(event.ctx.run.id);
    if (event.phase === "turn") {
      logger.info("Suspending after turn", { turn: event.turn });
    }
  },
  onChatResume: async (event) => {
    // Re-initialize after waking up
    logger.info("Resumed", { phase: event.phase });
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});

export const myChat = chat.agent({
  id: "my-chat",
  preloadIdleTimeoutInSeconds: 10,
  exitAfterPreloadIdle: true,
  onPreload: async ({ chatId, clientData }) => {
    // Eagerly set up state. If no message comes, the run just ends.
    await initializeChat(chatId, clientData);
  },
  run: async ({ messages, signal }) => {
    return streamText({ model: anthropic("claude-sonnet-4-5"), messages, abortSignal: signal });
  },
});