本地接口调用OpenAI接口，初探OpenAI的Function calling

由我们对话式的生成式人工智能到我们所谓的AI Agent演进，函数式调用是当前可以看到最有机会的方式。

用户可以用日常语言来让AI决策到底使用哪个接口来完成用户的任务，也可以通过用户的对话抽离出接口参数。

可以参考：

https://platform.openai.com/docs/guides/function-calling

https://cookbook.openai.com/examples/how_to_call_functions_with_chat_model

下面我简单实现一个官方的demo，先安装python依赖

pip install openai

from openai import OpenAI
import json


client = OpenAI(api_key="sk-*****************************")

# Example dummy function hard coded to return the same weather
# In production, this could be your backend API or an external API
def get_current_weather(location, unit="fahrenheit"):
    """Get the current weather in a given location"""
    if "tokyo" in location.lower():
        return json.dumps({"location": "Tokyo", "temperature": "10", "unit": unit})
    elif "san francisco" in location.lower():
        return json.dumps({"location": "San Francisco", "temperature": "72", "unit": unit})
    elif "paris" in location.lower():
        return json.dumps({"location": "Paris", "temperature": "22", "unit": unit})
    else:
        return json.dumps({"location": location, "temperature": "unknown"})

def run_conversation():
    # Step 1: send the conversation and available functions to the model
    messages = [{"role": "user", "content": "What's the weather like in San Francisco, Tokyo, and Paris?"}]
    tools = [
        {
            "type": "function",
            "function": {
                "name": "get_current_weather",
                "description": "Get the current weather in a given location",
                "parameters": {
                    "type": "object",
                    "properties": {
                        "location": {
                            "type": "string",
                            "description": "The city and state, e.g. San Francisco, CA",
                        },
                        "unit": {"type": "string", "enum": ["celsius", "fahrenheit"]},
                    },
                    "required": ["location"],
                },
            },
        }
    ]
    response = client.chat.completions.create(
        model="gpt-3.5-turbo-0125",
        messages=messages,
        tools=tools,
        tool_choice="auto",  # auto is default, but we'll be explicit
    )
    response_message = response.choices[0].message
    tool_calls = response_message.tool_calls
    # Step 2: check if the model wanted to call a function
    if tool_calls:
        # Step 3: call the function
        # Note: the JSON response may not always be valid; be sure to handle errors
        available_functions = {
            "get_current_weather": get_current_weather,
        }  # only one function in this example, but you can have multiple
        messages.append(response_message)  # extend conversation with assistant's reply
        # Step 4: send the info for each function call and function response to the model
        for tool_call in tool_calls:
            function_name = tool_call.function.name
            function_to_call = available_functions[function_name]
            function_args = json.loads(tool_call.function.arguments)
            function_response = function_to_call(
                location=function_args.get("location"),
                unit=function_args.get("unit"),
            )
            messages.append(
                {
                    "tool_call_id": tool_call.id,
                    "role": "tool",
                    "name": function_name,
                    "content": function_response,
                }
            )  # extend conversation with function response
        second_response = client.chat.completions.create(
            model="gpt-3.5-turbo-0125",
            messages=messages,
        )  # get a new response from the model where it can see the function response
        return second_response
print(run_conversation())

可以看到返回

ChatCompletion(id='chatcmpl-**', choices=[Choice(finish_reason='stop', index=0, logprobs=None, message=ChatCompletionMessage(content='Currently in San Francisco, the temperature is 72°C. In Tokyo, the temperature is 10°C. And in Paris, the temperature is 22°C.', role='assistant', function_call=None, tool_calls=None))], created=1711365951, model='gpt-35-turbo', object='chat.completion', system_fingerprint='fp_2f57f81c11', usage=CompletionUsage(completion_tokens=33, prompt_tokens=169, total_tokens=202))

你的openai的apikey可以在：https://platform.openai.com/api-keys获取