使用子代理构建个人助理

from langchain.tools import tool

@tool
def create_calendar_event(
    title: str,
    start_time: str,       # ISO 格式: "2024-01-15T14:00:00"
    end_time: str,         # ISO 格式: "2024-01-15T15:00:00"
    attendees: list[str],  # 电子邮件地址
    location: str = ""
) -> str:
    """创建一个日历事件。需要精确的 ISO 日期时间格式。"""
    # 桩代码: 实际中，这里会调用 Google Calendar API、Outlook API 等。
    return f"事件已创建: {title}，时间从 {start_time} 到 {end_time}，有 {len(attendees)} 位参与者"


@tool
def send_email(
    to: list[str],  # 电子邮件地址
    subject: str,
    body: str,
    cc: list[str] = []
) -> str:
    """通过电子邮件 API 发送邮件。需要格式正确的地址。"""
    # 桩代码: 实际中，这里会调用 SendGrid、Gmail API 等。
    return f"电子邮件已发送给 {', '.join(to)} - 主题: {subject}"


@tool
def get_available_time_slots(
    attendees: list[str],
    date: str,  # ISO 格式: "2024-01-15"
    duration_minutes: int
) -> list[str]:
    """检查特定日期给定参与者的日历可用性。"""
    # 桩代码: 实际中，这里会查询日历 API
    return ["09:00", "14:00", "16:00"]

from datetime import date

from langchain.agents import create_agent


CALENDAR_AGENT_PROMPT = (
    f"今天的日期是 {date.today().isoformat()}。"
    "你是一个日历调度助手。"
    "解析自然语言的调度请求（例如，'下周二下午2点'）"
    "为正确的 ISO 日期时间格式。"
    "在需要时使用 get_available_time_slots 检查可用性。"
    "如果没有合适的时间段，请停止并在回复中确认不可用。"
    "使用 create_calendar_event 来安排事件。"
    "在最终回复中始终确认已安排的内容。"
)

calendar_agent = create_agent(
    model,
    tools=[create_calendar_event, get_available_time_slots],
    system_prompt=CALENDAR_AGENT_PROMPT,
)

query = "安排一个明天下午2点开始、时长1小时的团队会议"

stream = calendar_agent.stream_events(
    {"messages": [{"role": "user", "content": query}]},
    version="v3",
)
for kind, item in stream.interleave("messages", "tool_calls"):
    if kind == "messages":
        for token in item.text:
            print(token, end="", flush=True)
    elif kind == "tool_calls":
        print(f"\n工具调用: {item.tool_name}({item.input})")
        print(f"工具结果: {item.output}")

================================== Ai 消息 ==================================
工具调用:
  get_available_time_slots (call_EIeoeIi1hE2VmwZSfHStGmXp)
 调用 ID: call_EIeoeIi1hE2VmwZSfHStGmXp
  参数:
    attendees: []
    date: 2024-06-18
    duration_minutes: 60
================================= 工具消息 =================================
名称: get_available_time_slots

["09:00", "14:00", "16:00"]
================================== Ai 消息 ==================================
工具调用:
  create_calendar_event (call_zgx3iJA66Ut0W8S3NpT93kEB)
 调用 ID: call_zgx3iJA66Ut0W8S3NpT93kEB
  参数:
    title: Team Meeting
    start_time: 2024-06-18T14:00:00
    end_time: 2024-06-18T15:00:00
    attendees: []
================================= 工具消息 =================================
名称: create_calendar_event

事件已创建: Team Meeting，时间从 2024-06-18T14:00:00 到 2024-06-18T15:00:00，有 0 位参与者
================================== Ai 消息 ==================================

团队会议已安排在明天，6月18日，下午2:00开始，持续1小时。如果您需要添加参与者或地点，请告诉我！

EMAIL_AGENT_PROMPT = (
    "你是一个电子邮件助手。"
    "根据自然语言请求撰写专业的电子邮件。"
    "提取收件人信息并制作合适的主题行和正文。"
    "使用 send_email 来发送消息。"
    "在最终回复中始终确认已发送的内容。"
)

email_agent = create_agent(
    model,
    tools=[send_email],
    system_prompt=EMAIL_AGENT_PROMPT,
)

query = "给设计团队发一封关于审查新原型的提醒邮件"

stream = email_agent.stream_events(
    {"messages": [{"role": "user", "content": query}]},
    version="v3",
)
for kind, item in stream.interleave("messages", "tool_calls"):
    if kind == "messages":
        for token in item.text:
            print(token, end="", flush=True)
    elif kind == "tool_calls":
        print(f"\n工具调用: {item.tool_name}({item.input})")
        print(f"工具结果: {item.output}")

================================== Ai 消息 ==================================
工具调用:
  send_email (call_OMl51FziTVY6CRZvzYfjYOZr)
 调用 ID: call_OMl51FziTVY6CRZvzYfjYOZr
  参数:
    to: ['design-team@example.com']
    subject: Reminder: Please Review the New Mockups
    body: Hi Design Team,

This is a friendly reminder to review the new mockups at your earliest convenience. Your feedback is important to ensure that we stay on track with our project timeline.

Please let me know if you have any questions or need additional information.

Thank you!

Best regards,
================================= 工具消息 =================================
名称: send_email

电子邮件已发送给 design-team@example.com - 主题: Reminder: Please Review the New Mockups
================================== Ai 消息 ==================================

我已经给设计团队发送了提醒邮件，请求他们审查新的原型。如果您需要就这个话题进行进一步的沟通，请告诉我！

@tool
def schedule_event(request: str) -> str:
    """使用自然语言安排日历事件。

    当用户想要创建、修改或检查日历预约时使用此工具。
    处理日期/时间解析、可用性检查和事件创建。

    输入：自然语言调度请求（例如，'下周二下午2点与设计团队开会'）
    """
    result = calendar_agent.invoke({
        "messages": [{"role": "user", "content": request}]
    })
    return result["messages"][-1].text


@tool
def manage_email(request: str) -> str:
    """使用自然语言发送电子邮件。

    当用户想要发送通知、提醒或任何电子邮件通信时使用此工具。
    处理收件人提取、主题生成和邮件撰写。

    输入：自然语言电子邮件请求（例如，'给他们发一封关于会议的提醒'）
    """
    result = email_agent.invoke({
        "messages": [{"role": "user", "content": request}]
    })
    return result["messages"][-1].text

SUPERVISOR_PROMPT = (
    "你是一个乐于助人的个人助理。"
    "你可以安排日历事件和发送电子邮件。"
    "将用户请求分解为适当的工具调用，并协调结果。"
    "当一个请求涉及多个操作时，请适当顺序或并行使用多个工具。"
)

supervisor_agent = create_agent(
    model,
    tools=[schedule_event, manage_email],
    system_prompt=SUPERVISOR_PROMPT,
)

query = "安排明天上午9点的团队站会"

stream = supervisor_agent.stream_events(
    {"messages": [{"role": "user", "content": query}]},
    version="v3",
)
for kind, item in stream.interleave("messages", "tool_calls"):
    if kind == "messages":
        for token in item.text:
            print(token, end="", flush=True)
    elif kind == "tool_calls":
        print(f"\n工具调用: {item.tool_name}({item.input})")
        print(f"工具结果: {item.output}")

================================== Ai 消息 ==================================
工具调用:
  schedule_event (call_mXFJJDU8bKZadNUZPaag8Lct)
 调用 ID: call_mXFJJDU8bKZadNUZPaag8Lct
  参数:
    request: 安排明天上午9点有 Alice 和 Bob 参加的团队站会。
================================= 工具消息 =================================
名称: schedule_event

明天上午9:00有 Alice 和 Bob 参加的团队站会已安排好。如果您需要进行任何更改或添加更多细节，请告诉我！
================================== Ai 消息 ==================================

明天上午9:00有 Alice 和 Bob 参加的团队站会已安排好。如果您需要进一步的安排或调整，请告诉我！

query = (
    "安排一个下周二下午2点开始、时长1小时的与设计团队的会议，"
    "并且给他们发一封关于审查新原型的电子邮件提醒。"
)

stream = supervisor_agent.stream_events(
    {"messages": [{"role": "user", "content": query}]},
    version="v3",
)
for kind, item in stream.interleave("messages", "tool_calls"):
    if kind == "messages":
        for token in item.text:
            print(token, end="", flush=True)
    elif kind == "tool_calls":
        print(f"\n工具调用: {item.tool_name}({item.input})")
        print(f"工具结果: {item.output}")

================================== Ai 消息 ==================================
工具调用:
  schedule_event (call_YA68mqF0koZItCFPx0kGQfZi)
 调用 ID: call_YA68mqF0koZItCFPx0kGQfZi
  参数:
    request: 下周二下午2点开始，时长1小时的与设计团队的会议
  manage_email (call_XxqcJBvVIuKuRK794ZIzlLxx)
 调用 ID: call_XxqcJBvVIuKuRK794ZIzlLxx
  参数:
    request: 给设计团队发一封关于在我们下周二下午2点的会议前审查新原型的电子邮件提醒
================================= 工具消息 =================================
名称: schedule_event

您与设计团队的会议已安排在下周二，6月18日，下午2:00到3:00。如果您需要添加更多细节或进行任何更改，请告诉我！
================================= 工具消息 =================================
名称: manage_email

我已经给设计团队发送了一封电子邮件提醒，请求他们审查新的原型。如果您需要包含更多信息或收件人，请告诉我！
================================== Ai 消息 ==================================

您与设计团队的会议已安排在下周二，6月18日，下午2:00到3:00。

我也给设计团队发送了一封电子邮件提醒，请他们审查新的原型。

如果您想在会议中添加更多细节或在电子邮件中包含更多信息，请告诉我！

from langchain.agents import create_agent
from langchain.agents.middleware import HumanInTheLoopMiddleware 
from langgraph.checkpoint.memory import InMemorySaver 


calendar_agent = create_agent(
    model,
    tools=[create_calendar_event, get_available_time_slots],
    system_prompt=CALENDAR_AGENT_PROMPT,
    middleware=[
        HumanInTheLoopMiddleware(
            interrupt_on={"create_calendar_event": True},
            description_prefix="日历事件待批准",
        ),
    ],
)

email_agent = create_agent(
    model,
    tools=[send_email],
    system_prompt=EMAIL_AGENT_PROMPT,
    middleware=[
        HumanInTheLoopMiddleware(
            interrupt_on={"send_email": True},
            description_prefix="出站电子邮件待批准",
        ),
    ],
)

supervisor_agent = create_agent(
    model,
    tools=[schedule_event, manage_email],
    system_prompt=SUPERVISOR_PROMPT,
    checkpointer=InMemorySaver(),
)

query = (
    "安排一个下周二下午2点开始、时长1小时的与设计团队的会议，"
    "并且给他们发一封关于审查新原型的电子邮件提醒。"
)

config = {"configurable": {"thread_id": "6"}}

interrupts = []
stream = supervisor_agent.stream_events(
    {"messages": [{"role": "user", "content": query}]},
    config,
    version="v3",
)
for kind, item in stream.interleave("messages", "tool_calls"):
    if kind == "messages":
        for token in item.text:
            print(token, end="", flush=True)
    elif kind == "tool_calls":
        print(f"\n工具调用: {item.tool_name}({item.input})")
if stream.interrupted:
    for interrupt_ in stream.interrupts:
        interrupts.append(interrupt_)
        print(f"\n已中断: {interrupt_.id}")

================================== Ai 消息 ==================================
工具调用:
  schedule_event (call_t4Wyn32ohaShpEZKuzZbl83z)
 调用 ID: call_t4Wyn32ohaShpEZKuzZbl83z
  参数:
    request: 安排一个下周二下午2点开始、时长1小时的与设计团队的会议。
  manage_email (call_JWj4vDJ5VMnvkySymhCBm4IR)
 调用 ID: call_JWj4vDJ5VMnvkySymhCBm4IR
  参数:
    request: 给设计团队发一封关于在我们下周二下午2点的会议前审查新原型的电子邮件提醒。

已中断: 4f994c9721682a292af303ec1a46abb7

已中断: 2b56f299be313ad8bc689eff02973f16

for interrupt_ in interrupts:
    for request in interrupt_.value["action_requests"]:
        print(f"已中断: {interrupt_.id}")
        print(f"{request['description']}\n")

已中断: 4f994c9721682a292af303ec1a46abb7
日历事件待批准

工具: create_calendar_event
参数: {'title': 'Meeting with the Design Team', 'start_time': '2024-06-18T14:00:00', 'end_time': '2024-06-18T15:00:00', 'attendees': ['design team']}

已中断: 2b56f299be313ad8bc689eff02973f16
出站电子邮件待批准

工具: send_email
参数: {'to': ['designteam@example.com'], 'subject': 'Reminder: Review New Mockups Before Meeting Next Tuesday at 2pm', 'body': "Hello Team,\n\nThis is a reminder to review the new mockups ahead of our meeting scheduled for next Tuesday at 2pm. Your feedback and insights will be valuable for our discussion and next steps.\n\nPlease ensure you've gone through the designs and are ready to share your thoughts during the meeting.\n\nThank you!\n\nBest regards,\n[Your Name]"}

import { Command } from "@langchain/langgraph";

const resume: Record<string, any> = {};
for (const interrupt of interrupts) {
  const actionRequest = interrupt.payload.actionRequests[0];
  if (actionRequest.name === "send_email") {
    // 编辑邮件
    const editedAction = { ...actionRequest };
    editedAction.args.subject = "Mockups reminder";
    resume[interrupt.interruptId] = {
      decisions: [{ type: "edit", editedAction }]
    };
  } else {
    resume[interrupt.interruptId] = { decisions: [{ type: "approve" }] };
  }
}

const resumeStream = await supervisorAgent.streamEvents(
  new Command({ resume }),
  { ...config, version: "v3" }
);

await Promise.all([
  (async () => {
    for await (const message of resumeStream.messages) {
      for await (const token of message.text) {
        process.stdout.write(token);
      }
    }
  })(),
  (async () => {
    for await (const call of resumeStream.toolCalls) {
      console.log(`\nTool call: ${call.name}(${JSON.stringify(call.input)})`);
    }
  })(),
]);

import { getCurrentTaskInput } from "@langchain/langgraph";
import { type BuiltInState, HumanMessage } from "langchain";

const scheduleEvent = tool(
  async ({ request }, config) => {
    // 自定义子代理接收的上下文
    // 从 config 中访问完整的线程消息
    const currentMessages = getCurrentTaskInput<BuiltInState>(config).messages;
    const originalUserMessage = currentMessages.find(HumanMessage.isInstance);
    const prompt = `
You are assisting with the following user inquiry:

${originalUserMessage?.content || "No context available"}

You are tasked with the following sub-request:

${request}
    `.trim();

    const result = await calendarAgent.invoke({
      messages: [{ role: "user", content: prompt }],
    });
    const lastMessage = result.messages[result.messages.length - 1];
    return lastMessage.text;
  },
  {
    name: "schedule_event",
    description: "Schedule calendar events using natural language.",
    schema: z.object({
      request: z.string().describe("Natural language scheduling request"),
    }),
  }
);

const scheduleEvent = tool(
  async ({ request }) => {
    const result = await calendarAgent.invoke({
      messages: [{ role: "user", content: request }]
    });

    const lastMessage = result.messages[result.messages.length - 1];

    // 选项 1：仅返回确认消息
    return lastMessage.text;

    // 选项 2：返回结构化数据
    // return JSON.stringify({
    //   status: "success",
    //   event_id: "evt_123",
    //   summary: lastMessage.text
    // });
  },
  {
    name: "schedule_event",
    description: "Schedule calendar events using natural language.",
    schema: z.object({
      request: z.string().describe("Natural language scheduling request"),
    }),
  }
);