AI Agent（智能体）从零开始完整教程（小白也能看懂）#

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import datetime
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def get_weather(city):
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    """模拟查询天气（真实项目这里调用天气 API）"""
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    weather_data = {
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        "beijing": "25°C，晴",
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        "shanghai": "28°C，多云",
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        "guangzhou": "31°C，有雨",
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    }
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    return weather_data.get(city.lower(), "查不到这个城市的天气")
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def calculate(expression):
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    """计算数学表达式"""
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    try:
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        return str(eval(expression))
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    except:
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        return "计算失败"
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def get_time():
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    """获取当前时间"""
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    return datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
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# 工具注册表：Agent 知道的"能力清单"
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TOOLS = {
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    "get_weather": {"fn": get_weather, "desc": "查询天气，参数：城市名"},
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    "calculate": {"fn": calculate, "desc": "数学计算，参数：算式"},
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    "get_time": {"fn": get_time, "desc": "获取当前时间，无参数"},
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}

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from tools import TOOLS
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class SimpleAgent:
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    def __init__(self):
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        # 这里存"对话记忆"
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        self.memory = []
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    def parse_intent(self, text):
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        """模拟大模型的'思考'：根据输入决定调用哪个工具
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        真实项目里这里是调用 LLM 让它判断"""
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        if "天气" in text:
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            # 提取城市名
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            for city in ["北京", "上海", "广州", "beijing", "shanghai", "guangzhou"]:
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                if city.lower() in text.lower():
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                    return "get_weather", city.lower()
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            return "get_weather", "beijing"
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        if "时间" in text or "几点" in text:
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            return "get_time", None
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        if any(c in text for c in "+-*/") or "算" in text:
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            return "calculate", text
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        return None, None
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    def run(self, user_input):
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        """ReAct 循环：思考 → 行动 → 观察 → 回答"""
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        self.memory.append(f"用户: {user_input}")
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        # 思考：决定调用哪个工具
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        tool_name, arg = self.parse_intent(user_input)
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        if tool_name is None:
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            reply = "抱歉，我只能查天气、算数、看时间哦。"
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        else:
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            # 行动：调用工具
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            tool = TOOLS[tool_name]
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            result = tool["fn"](arg) if arg else tool["fn"]()
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            # 观察 + 回答
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            reply = f"（调用了 {tool_name}，结果是：{result}）\n{result}"
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        self.memory.append(f"Agent: {reply}")
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        return reply
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# 使用
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if __name__ == "__main__":
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    agent = SimpleAgent()
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    while True:
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        user = input("你: ")
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        if user.lower() in ("exit", "quit"):
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            break
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        print(agent.run(user))