本期接着前文的**智能Agent实战指南:从入门到精通(工具)**继续来进行探讨Agent嵌入记忆组件。需求:北京明天的天气怎么样?上海呢?(是要通过两次对话实现)
1、传统方式实现
1.1 以ReAct方式
python
from langchain_classic.memory import ConversationBufferMemory
from langchain_classic.agents import AgentType, initialize_agent
from langchain_classic.tools import Tool
from langchain_community.tools import TavilySearchResults
from langchain_openai import ChatOpenAI
import os
import dotenv
dotenv.load_dotenv()
# 读取配置文件
os.environ["TAVILY_API_KEY"] = os.getenv("TAVILY_API_KEY")
# 获取Tavily搜索工具实例
search = TavilySearchResults(max_results = 3)
search_tool = Tool(
func = search.run,
name = "search",
description = "用于检索互联网上的信息",
)
# 获取大模型
os.environ['OPENAI_API_KEY'] = os.getenv("OPENAI_API_KEY")
os.environ['OPENAI_BASE_URL'] = os.getenv("OPENAI_BASE_URL")
llm = ChatOpenAI(
model="gpt-4o-mini",
temperature=0,
)
# 获取记忆的实例:ConversationBufferMemory
memory = ConversationBufferMemory(
return_messages= True,
memory_key= "chat_history" # 必须设置memory_key的值为chat_history,因为提示词模版中使用的是chat_history,二者必须一致
)
# 创建agent示例
agent = AgentType.CONVERSATIONAL_REACT_DESCRIPTION
# 创建agentExecutor实例
agent_execute = initialize_agent(
llm =llm,
agent = agent,
tools = [search_tool],
verbose = True,
memory = memory,
)
# 通过agentExecutor调用invoke(),并得到响应
result = agent_execute.invoke("查询西安今天天气情况")
# 处理响应数据
print(result)

此时再询问上海的:
python
result = agent_execute.invoke("上海呢?")
print(result)
这里我们的问题只是"上海呢?"具体指代的就是上海的天气,通过嵌入的记忆获取。

1.2 以function_call方式
python
from langchain_classic.memory import ConversationBufferMemory
from langchain_classic.agents import AgentType, initialize_agent
from langchain_classic.tools import Tool
from langchain_community.tools import TavilySearchResults
from langchain_openai import ChatOpenAI
import os
import dotenv
dotenv.load_dotenv()
# 读取配置文件
os.environ["TAVILY_API_KEY"] = os.getenv("TAVILY_API_KEY")
# 获取Tavily搜索工具实例
search = TavilySearchResults(max_results = 3)
search_tool = Tool(
func = search.run,
name = "search",
description = "用于检索互联网上的信息",
)
# 获取大模型
os.environ['OPENAI_API_KEY'] = os.getenv("OPENAI_API_KEY")
os.environ['OPENAI_BASE_URL'] = os.getenv("OPENAI_BASE_URL")
llm = ChatOpenAI(
model="gpt-4o-mini",
temperature=0,
)
# 获取记忆的实例:ConversationBufferMemory
memory = ConversationBufferMemory(
return_messages= True,
memory_key= "chat_history" # 必须设置memory_key的值为chat_history,因为提示词模版中使用的是chat_history,二者必须一致
)
# 创建agent示例
agent = AgentType.OPENAI_FUNCTIONS
# 创建agentExecutor实例
agent_execute = initialize_agent(
llm =llm,
agent = agent,
tools = [search_tool],
verbose = True,
memory = memory,
)
# 通过agentExecutor调用invoke(),并得到响应
response = agent_execute.invoke({"input":"今天是周几"})
# 处理响应数据
print(response)
2、通用方式实现
2.1 以function_call方式
python
from langchain_classic.memory import ConversationBufferMemory
from langchain_core.prompts import ChatPromptTemplate
from langchain_classic.agents import AgentType, initialize_agent, create_tool_calling_agent, AgentExecutor
from langchain_classic.tools import Tool
from langchain_community.tools import TavilySearchResults
from langchain_openai import ChatOpenAI
import os
import dotenv
dotenv.load_dotenv()
# 读取配置文件
os.environ["TAVILY_API_KEY"] = os.getenv("TAVILY_API_KEY")
# 获取Tavily搜索工具实例
search = TavilySearchResults(max_results = 3)
# 2、获取对应工具实例
search_tool = Tool(
func = search.run,
name = "search",
description = "用于检索互联网上的信息",
)
# 3、获取大模型
os.environ['OPENAI_API_KEY'] = os.getenv("OPENAI_API_KEY")
os.environ['OPENAI_BASE_URL'] = os.getenv("OPENAI_BASE_URL")
llm = ChatOpenAI(
model="gpt-4o-mini",
temperature=0,
)
memory = ConversationBufferMemory(
return_messages=True,
memory_key="chat_history",
)
# 4、提示词模版(ChatPromptTemplate为例)
prompt_template = ChatPromptTemplate.from_messages([
("system","你是一个乐于助人的ai助手,根据用户的提问,必要时调用search工具,使用互联网检索数据"),
("system","{chat_history}"), # 添加一个chat_history的变量,用于记录上下文记忆
("human","{input}"),
("system","{agent_scratchpad}"), # agent_scratchpad必须声明 agent_scratchpad 放在 input 之前确实可能导致输出重复或混乱
])
# 5、获取Agent实例:create_tool_calling_agent()
agent = create_tool_calling_agent(
llm = llm,
prompt = prompt_template,
tools = [search_tool],
)
# 6、获取AgentExecutor实例
agent_executor = AgentExecutor(
agent = agent,
tools = [search_tool],
verbose = True,
memory = memory,
)
# 7、通过AgentExecutor实例调用invoke方法,得到响应
response = agent_executor.invoke({"input":"查询今天的西安天气情况"})
# 8、处理响应
print(response)

此时继续询问上海的:
python
response = agent_executor.invoke({"input":"上海呢?"})
print(response)

2.2 以ReAct方式
直接使用现成的提示词模版
python
from langchain_classic import hub
from langchain_core.prompts import ChatPromptTemplate, PromptTemplate
from langchain_classic.agents import AgentType, initialize_agent, create_tool_calling_agent, AgentExecutor, create_react_agent
from langchain_core.tools import StructuredTool
from langchain_classic.tools import Tool
from langchain_community.tools import TavilySearchResults
from langchain_openai import ChatOpenAI
import os
import dotenv
dotenv.load_dotenv()
# 读取配置文件
os.environ["TAVILY_API_KEY"] = os.getenv("TAVILY_API_KEY")
# 获取Tavily搜索工具实例
search = TavilySearchResults(max_results = 3)
# 2、获取对应工具实例
search_tool = Tool(
func = search.run,
name = "search",
description = "用于检索互联网上的信息",
)
# 3、获取大模型
os.environ['OPENAI_API_KEY'] = os.getenv("OPENAI_API_KEY")
os.environ['OPENAI_BASE_URL'] = os.getenv("OPENAI_BASE_URL")
llm = ChatOpenAI(
model="gpt-4o-mini",
temperature=0,
)
# 4、使用LangChain Hub中的官方ReAct提示模板
prompt_template = hub.pull("hwchase17/react-chat")
memory = ConversationBufferMemory(
return_messages= True,
memory_key="chat_history",
)
# 5、获取Agent实例:create_react_agent()
agent = create_react_agent(
llm = llm,
prompt = prompt_template,
tools = [search_tool],
)
# 6、获取AgentExecutor实例
agent_executor = AgentExecutor(
agent = agent,
tools = [search_tool],
verbose = True,
memory = memory,
)
# 7、通过AgentExecutor实例调用invoke方法,得到响应
response = agent_executor.invoke({"input":"查询今天的西安天气情况"})
# 8、处理响应
print(response)

指定某一天的:
python
response = agent_executor.invoke({"input":"西安2026年3月30日的呢"})
print(response)
