11、让LLM更懂FunctionCalling返回值

11、让LLM更懂FunctionCalling返回值

让LLM更懂函数返回类型

当前,在向AI模型提供函数返回类型元数据这一领域,尚未有清晰明确的行业标准。当出现返回类型属性的名称无法让大语言模型(LLM)准确推断其内容,或者需要关联其他上下文信息、处理指令到返回类型,以此来实现方案建模或增强方案效果的情况时,可考虑运用以下技术:

  1. 在对函数进行描述的过程中,清晰地给出函数返回类型的相关信息。
  2. 将函数返回类型的模式(schema)作为函数返回值的组成部分一并提供。

值得注意的是,在决定采用上述任何一种技术之前,最好先为返回类型属性拟定更具描述性的名称。这是因为这一举措是提升大语言模型(LLM)对返回类型理解程度的最直接途径,而且从令牌使用的角度来看,这种做法也能有效控制成本,具有较高的性价比。

准备工作

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using PolyglotKernel= Microsoft.DotNet.Interactive.Kernel;// 引入交互式的内核命名空间,以便用户输入
using Microsoft.SemanticKernel.Connectors.OpenAI;

var aiProviderCode = await PolyglotKernel.GetInputAsync("请输入AI服务提供商编码:");

var kernel = GetKernel(aiProviderCode);
var chatCompletionService = kernel.GetRequiredService<IChatCompletionService>();

一、在函数描述中提供函数返回类型信息

有两种方法,但都需要手动添加返回类型元数据信息,当返回类型变更时需要同步更改,适用于返回类型比较稳定的场景。

1. 在函数中提供返回类型描述

以下定义了一个空气插件用于获取天气信息,包含温度、湿度、露点温度和风速信息。通过直接在[KernelFunction]中定义[Desciption]用自然语言直接描述返回值的单位信息。
此种情况适用于:

  • 某些模型可能对函数描述的大小有限制
  • 如果类型信息不重要
  • 需要优先考虑最大限度地减少令牌消耗
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using System.ComponentModel;

/// <summary>
/// A plugin that provides the current weather data and describes the return type in the function <see cref="DescriptionAttribute"/>.
/// </summary>
private sealed class WeatherPlugin1
{
[KernelFunction]
[Description("Returns current weather: Data1 - Temperature (°C), Data2 - Humidity (%), Data3 - Dew Point (°C), Data4 - Wind Speed (km/h)")]
public WeatherData GetWeatherData()
{
return new WeatherData()
{
Data1 = 35.0, // Temperature in degrees Celsius
Data2 = 20.0, // Humidity in percentage
Data3 = 10.0, // Dew point in degrees Celsius
Data4 = 15.0 // Wind speed in kilometers per hour
};
}
public sealed class WeatherData
{
public double Data1 { get; set; }
public double Data2 { get; set; }
public double Data3 { get; set; }
public double Data4 { get; set; }
}
}
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kernel.Plugins.Clear();
kernel.ImportPluginFromType<WeatherPlugin1>();

OpenAIPromptExecutionSettings settings = new() { FunctionChoiceBehavior = FunctionChoiceBehavior.Auto() };
FunctionResult result = await kernel.InvokePromptAsync("What is the current weather?", new(settings));
Console.Write(result);
The current weather is as follows:
- Temperature: 35°C
- Humidity: 20%
- Dew Point: 10°C
- Wind Speed: 15 km/h

查看日志,可以看出发出的请求数据包如下:
第一次请求的数据:

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{
"tools": [
{
"function": {
"description": "Returns current weather: Data1 - Temperature (°C), Data2 - Humidity (%), Data3 - Dew Point (°C), Data4 - Wind Speed (km/h)",
"name": "WeatherPlugin1-GetWeatherData",
"strict": false,
"parameters": {
"type": "object",
"required": [],
"properties": {}
}
},
"type": "function"
}
],
"messages": [
{
"role": "user",
"content": "What is the current weather?"
},
],
"model": "gpt-4o",
"tool_choice": "auto"
}

第二次请求的数据:

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{
"tools": [
{
"function": {
"description": "Returns current weather: Data1 - Temperature (°C), Data2 - Humidity (%), Data3 - Dew Point (°C), Data4 - Wind Speed (km/h)",
"name": "WeatherPlugin1-GetWeatherData",
"strict": false,
"parameters": {
"type": "object",
"required": [],
"properties": {}
}
},
"type": "function"
}
],
"messages": [
{
"role": "user",
"content": "What is the current weather?"
},
{
"role": "assistant",
"content": "",
"tool_calls": [
{
"id": "call_M9mfYHD8nLiFTiF0HOiLT2r2",
"function": {
"name": "WeatherPlugin1-GetWeatherData",
"arguments": "{}"
},
"type": "function"
}
]
},
{
"role": "tool",
"tool_call_id": "call_M9mfYHD8nLiFTiF0HOiLT2r2",
"content": "{"Data1":35,"Data2":20,"Data3":10,"Data4":15}"
}
],
"model": "gpt-4o",
"tool_choice": "auto"
}

2. 在函数描述中添加返回类型元数据

以下定义了一个空气插件用于获取天气信息,包含温度、湿度、露点温度和风速信息。通过直接在[KernelFunction]中定义[Description]来描述返回值的单位信息,其中[Description]中包含返回值的元数据信息:

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{
"type": "object",
"properties": {
"Data1": {
"description": "Temperature (°C)",
"type": "number"
},
"Data2": {
"description": "Humidity(%)",
"type": "number"
},
"Data3": {
"description": "Dew point (°C)",
"type": "number"
},
"Data4": {
"description": "Wind speed (km/h)",
"type": "number"
}
}
}
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using System.ComponentModel;

/// <summary>
/// A plugin that provides the current weather data and specifies the return type schema in the function <see cref="DescriptionAttribute"/>.
/// </summary>
private sealed class WeatherPlugin2
{
[KernelFunction]
[Description("""Returns current weather: {"type":"object","properties":{"Data1":{"description":"Temperature (°C)","type":"number"},"Data2":{"description":"Humidity(%)","type":"number"}, "Data3":{"description":"Dew point (°C)","type":"number"},"Data4":{"description":"Wind speed (km/h)","type":"number"}}}""")]
public WeatherData GetWeatherData()
{
return new WeatherData()
{
Data1 = 35.0, // Temperature in degrees Celsius
Data2 = 20.0, // Humidity in percentage
Data3 = 10.0, // Dew point in degrees Celsius
Data4 = 15.0 // Wind speed in kilometers per hour
};
}
public sealed class WeatherData
{
public double Data1 { get; set; }
public double Data2 { get; set; }
public double Data3 { get; set; }
public double Data4 { get; set; }
}
}
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kernel.Plugins.Clear();
kernel.ImportPluginFromType<WeatherPlugin2>();

OpenAIPromptExecutionSettings settings = new() { FunctionChoiceBehavior = FunctionChoiceBehavior.Auto() };
FunctionResult result = await kernel.InvokePromptAsync("What is the current weather?", new(settings));
Console.WriteLine(result);
The current weather is as follows:
- Temperature: 35°C
- Humidity: 20%
- Dew point: 10°C
- Wind speed: 15 km/h

查看日志,可以看出发出的请求数据包如下:

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{
"tools": [
{
"function": {
"description": "Returns current weather: {"type":"object","properties":{"Data1":{"description":"Temperature (°C)","type":"number"},"Data2":{"description":"Humidity(%)","type":"number"}, "Data3":{"description":"Dew point (°C)","type":"number"},"Data4":{"description":"Wind speed (km/h)","type":"number"}}}",
"name": "WeatherPlugin2-GetWeatherData",
"strict": false,
"parameters": {
"type": "object",
"required": [],
"properties": {}
}
},
"type": "function"
}
],
"messages": [
{
"role": "user",
"content": "What is the current weather?"
},
{
"role": "assistant",
"content": "",
"tool_calls": [
{
"id": "call_HjCyu9atNmesxuOc0cAyeafP",
"function": {
"name": "WeatherPlugin2-GetWeatherData",
"arguments": "{}"
},
"type": "function"
}
]
},
{
"role": "tool",
"tool_call_id": "call_HjCyu9atNmesxuOc0cAyeafP",
"content": "{"Data1":35,"Data2":20,"Data3":10,"Data4":15}"
}
],
"model": "gpt-4o",
"tool_choice": "auto"
}

二、实现函数返回值重写过滤器

之前介绍了可以通过实现自定义IAutoFunctionInvocationFilter接口来实现请求重写。
以下定义了一个空气插件用于获取天气信息,包含温度、湿度、露点温度和风速信息。并没有在[KernelFucntion]中添加返回值描述,而是在返回类型中定义[Description]来描述各个属性,然后通过过滤器来重写返回值,将返回类型的元数据包含在其中。

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/// <summary>
/// A plugin that provides the current weather data and provides descriptions for the return type properties.
/// </summary>
private sealed class WeatherPlugin3
{
[KernelFunction]
public WeatherData GetWeatherData()
{
return new WeatherData()
{
Data1 = 35.0, // Temperature in degrees Celsius
Data2 = 20.0, // Humidity in percentage
Data3 = 10.0, // Dew point in degrees Celsius
Data4 = 15.0 // Wind speed in kilometers per hour
};
}

public sealed class WeatherData
{
[Description("Temp (°C)")]
public double Data1 { get; set; }

[Description("Humidity (%)")]
public double Data2 { get; set; }

[Description("Dew point (°C)")]
public double Data3 { get; set; }

[Description("Wind speed (km/h)")]
public double Data4 { get; set; }
}
}
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/// <summary>
/// A auto function invocation filter that replaces the original function's result with a new result that includes both the original result and its schema.
/// </summary>
private sealed class AddReturnTypeSchemaFilter : IAutoFunctionInvocationFilter
{
public async Task OnAutoFunctionInvocationAsync(AutoFunctionInvocationContext context, Func<AutoFunctionInvocationContext, Task> next)
{
// Invoke the function
await next(context);
// Crete the result with the schema
FunctionResultWithSchema resultWithSchema = new()
{
Value = context.Result.GetValue<object>(), // Get the original result
Schema = context.Function.Metadata.ReturnParameter?.Schema // Get the function return type schema
};
// Return the result with the schema instead of the original one
context.Result = new FunctionResult(context.Result, resultWithSchema);
}
private sealed class FunctionResultWithSchema
{
public object? Value { get; set; }
public KernelJsonSchema? Schema { get; set; }
}
}
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kernel.AutoFunctionInvocationFilters.Add(new AddReturnTypeSchemaFilter());
// Import the plugin that provides descriptions for the return type properties.
// This additional information is used when extracting the schema from the return type.
kernel.Plugins.Clear();
kernel.ImportPluginFromType<WeatherPlugin3>();
OpenAIPromptExecutionSettings settings = new() { FunctionChoiceBehavior = FunctionChoiceBehavior.Auto() };
FunctionResult result = await kernel.InvokePromptAsync("What is the current weather?", new(settings));
Console.WriteLine(result);
The current weather is as follows:
- Temperature: 35°C
- Humidity: 20%
- Dew Point: 10°C
- Wind Speed: 15 km/h

查看日志,可以看出发出的请求如下:
第一次请求:

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{
"tools": [
{
"function": {
"description": "",
"name": "WeatherPlugin3-GetWeatherData",
"strict": false,
"parameters": {
"type": "object",
"required": [],
"properties": {}
}
},
"type": "function"
}
],
"messages": [
{
"role": "user",
"content": "What is the current weather?"
}
],
"model": "gpt-4o",
"tool_choice": "auto"
}

第二次请求:

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{
"tools": [
{
"function": {
"description": "",
"name": "WeatherPlugin3-GetWeatherData",
"strict": false,
"parameters": {
"type": "object",
"required": [],
"properties": {}
}
},
"type": "function"
}
],
"messages": [
{
"role": "user",
"content": "What is the current weather?"
},
{
"role": "assistant",
"content": "",
"tool_calls": [
{
"id": "call_wb7JgQOZ8e4jXgkclXmR7pik",
"function": {
"name": "WeatherPlugin3-GetWeatherData",
"arguments": "{}"
},
"type": "function"
}
]
},
{
"role": "tool",
"tool_call_id": "call_wb7JgQOZ8e4jXgkclXmR7pik",
"content": "{"Value":{"Data1":35,"Data2":20,"Data3":10,"Data4":15},"Schema":{"type":"object","properties":{"Data1":{"description":"Temp (°C)","type":"number"},"Data2":{"description":"Humidity (%)","type":"number"},"Data3":{"description":"Dew point (°C)","type":"number"},"Data4":{"description":"Wind speed (km/h)","type":"number"}}}}"
}
],
"model": "gpt-4o",
"tool_choice": "auto"
}
作者

步步为营

发布于

2025-04-11

更新于

2025-04-11

许可协议