LangChainHub 的思路真的很好,通过Hub的方式将Prompt 共享起来,大家可以通过很方便的手段,短短的几行代码就可以使用共享的Prompt。
我个人非常看好这个项目。
官方推荐使用LangChainHub,但是它在GitHub已经一年没有更新了, 倒是数据还在更新。
安装依赖
pip install langchainhub
Prompt
为了防止大家不能访问,我这里先把用到的模板复制一份出来。
HUMAN You are a helpful assistant. Help the user answer any questions. You have access to the following tools: {tools} In order to use a tool, you can use <tool></tool> and <tool_input></tool_input> tags. You will then get back a response in the form <observation></observation> For example, if you have a tool called 'search' that could run a google search, in order to search for the weather in SF you would respond: <tool>search</tool><tool_input>weather in SF</tool_input> <observation>64 degrees</observation> When you are done, respond with a final answer between <final_answer></final_answer>. For example: <final_answer>The weather in SF is 64 degrees</final_answer> Begin! Previous Conversation: {chat_history} Question: {input} {agent_scratchpad}
编写代码
代码主要部分是,定义了一个工具tool
,让Agent
执行,模拟了一个搜索引擎,让GPT利用工具对自身的内容进行扩展,从而完成复杂的任务。
from langchain import hub from langchain.agents import AgentExecutor, tool from langchain.agents.output_parsers import XMLAgentOutputParser from langchain_openai import ChatOpenAI model = ChatOpenAI( model="gpt-3.5-turbo", ) @tool def search(query: str) -> str: """Search things about current events.""" return "32 degrees" tool_list = [search] # Get the prompt to use - you can modify this! prompt = hub.pull("hwchase17/xml-agent-convo") # Logic for going from intermediate steps to a string to pass into model # This is pretty tied to the prompt def convert_intermediate_steps(intermediate_steps): log = "" for action, observation in intermediate_steps: log += ( f"<tool>{action.tool}</tool><tool_input>{action.tool_input}" f"</tool_input><observation>{observation}</observation>" ) return log # Logic for converting tools to string to go in prompt def convert_tools(tools): return "\n".join([f"{tool.name}: {tool.description}" for tool in tools]) agent = ( { "input": lambda x: x["input"], "agent_scratchpad": lambda x: convert_intermediate_steps( x["intermediate_steps"] ), } | prompt.partial(tools=convert_tools(tool_list)) | model.bind(stop=["</tool_input>", "</final_answer>"]) | XMLAgentOutputParser() ) agent_executor = AgentExecutor(agent=agent, tools=tool_list) message = agent_executor.invoke({"input": "whats the weather in New york?"}) print(f"message: {message}")
运行结果
➜ python3 test10.py message: {'input': 'whats the weather in New york?', 'output': 'The weather in New