ReACT介绍与llama_index ReActAgent实践

from llama_index.core.agent import ReActAgent  
from llama_index.core.tools import FunctionTool  
from llama_index.llms.gemini import Gemini  
  
  
# define sample Tool  
def multiply(a: int, b: int) -> int:  
    """Multiply two integers and returns the result integer"""  
    return a * b  
  
  
multiply_tool = FunctionTool.from_defaults(fn=multiply)  
  
# initialize llm  
llm = Gemini(api_key="AI...", transport="rest")  
  
# initialize ReAct agent  
agent = ReActAgent.from_tools([multiply_tool], llm=llm, verbose=True)  
  
resp = agent.query("计算85乘以9")  
  
print(resp.response)

[ChatMessage(role=<MessageRole.SYSTEM: 'system'>, content='\nYou are designed to help with a variety of tasks, from answering questions     to providing summaries to other types of analyses.\n\n## Tools\nYou have access to a wide variety of tools. You are responsible for using\nthe tools in any sequence you deem appropriate to complete the task at hand.\nThis may require breaking the task into subtasks and using different tools\nto complete each subtask.\n\nYou have access to the following tools:\n> Tool Name: multiply\nTool Description: multiply(a: int, b: int) -> int\nMultiply two integers and returns the result integer\nTool Args: {"type": "object", "properties": {"a": {"title": "A", "type": "integer"}, "b": {"title": "B", "type": "integer"}}, "required": ["a", "b"]}\n\n\n## Output Format\nPlease answer in the same language as the question and use the following format:\n\n```\nThought: The current language of the user is: (user\'s language). I need to use a tool to help me answer the question.\nAction: tool name (one of multiply) if using a tool.\nAction Input: the input to the tool, in a JSON format representing the kwargs (e.g. {"input": "hello world", "num_beams": 5})\n```\n\nPlease ALWAYS start with a Thought.\n\nPlease use a valid JSON format for the Action Input. Do NOT do this {\'input\': \'hello world\', \'num_beams\': 5}.\n\nIf this format is used, the user will respond in the following format:\n\n```\nObservation: tool response\n```\n\nYou should keep repeating the above format until you have enough information\nto answer the question without using any more tools. At that point, you MUST respond\nin the one of the following two formats:\n\n```\nThought: I can answer without using any more tools. I\'ll use the user\'s language to answer\nAnswer: [your answer here (In the same language as the user\'s question)]\n```\n\n```\nThought: I cannot answer the question with the provided tools.\nAnswer: [your answer here (In the same language as the user\'s question)]\n```\n\n## Current Conversation\nBelow is the current conversation consisting of interleaving human and assistant messages.\n\n', additional_kwargs={}), ChatMessage(role=<MessageRole.USER: 'user'>, content='计算85乘以9', additional_kwargs={})]

assistant: Thought: The current language of the user is: chinese. I need to use a tool to help me answer the question.
Action: multiply
Action Input: {"a": 85, "b": 9}

[ActionReasoningStep(thought='The current language of the user is: chinese. I need to use a tool to help me answer the question.', action='multiply', action_input={'a': 85, 'b': 9}), ObservationReasoningStep(observation='765')]

cur_step_output = 765

[TaskStep(task_id='1d8db1d0-f5e3-4bfa-bcef-8fc405f958ca', step_id='91e9a97a-5ae1-4900-bf77-690865976902', input=None, step_state={'is_first': False}, next_steps={}, prev_steps={}, is_ready=True)]

[ChatMessage(role=<MessageRole.SYSTEM: 'system'>, content='\nYou are designed to help with a variety of tasks, from answering questions     to providing summaries to other types of analyses.\n\n## Tools\nYou have access to a wide variety of tools. You are responsible for using\nthe tools in any sequence you deem appropriate to complete the task at hand.\nThis may require breaking the task into subtasks and using different tools\nto complete each subtask.\n\nYou have access to the following tools:\n> Tool Name: multiply\nTool Description: multiply(a: int, b: int) -> int\nMultiply two integers and returns the result integer\nTool Args: {"type": "object", "properties": {"a": {"title": "A", "type": "integer"}, "b": {"title": "B", "type": "integer"}}, "required": ["a", "b"]}\n\n\n## Output Format\nPlease answer in the same language as the question and use the following format:\n\n```\nThought: The current language of the user is: (user\'s language). I need to use a tool to help me answer the question.\nAction: tool name (one of multiply) if using a tool.\nAction Input: the input to the tool, in a JSON format representing the kwargs (e.g. {"input": "hello world", "num_beams": 5})\n```\n\nPlease ALWAYS start with a Thought.\n\nPlease use a valid JSON format for the Action Input. Do NOT do this {\'input\': \'hello world\', \'num_beams\': 5}.\n\nIf this format is used, the user will respond in the following format:\n\n```\nObservation: tool response\n```\n\nYou should keep repeating the above format until you have enough information\nto answer the question without using any more tools. At that point, you MUST respond\nin the one of the following two formats:\n\n```\nThought: I can answer without using any more tools. I\'ll use the user\'s language to answer\nAnswer: [your answer here (In the same language as the user\'s question)]\n```\n\n```\nThought: I cannot answer the question with the provided tools.\nAnswer: [your answer here (In the same language as the user\'s question)]\n```\n\n## Current Conversation\nBelow is the current conversation consisting of interleaving human and assistant messages.\n\n', additional_kwargs={}), ChatMessage(role=<MessageRole.USER: 'user'>, content='计算85乘以9', additional_kwargs={}), ChatMessage(role=<MessageRole.ASSISTANT: 'assistant'>, content="Thought: The current language of the user is: chinese. I need to use a tool to help me answer the question.\nAction: multiply\nAction Input: {'a': 85, 'b': 9}", additional_kwargs={}), ChatMessage(role=<MessageRole.USER: 'user'>, content='Observation: 765', additional_kwargs={})]

assistant: Thought: I can answer without using any more tools. I'll use the user's language to answer
Answer: 765