MAF1/MAF1.Core/Agents/Weather/WeatherAgent.cs

using MAF1.Core.Agents;
using MAF1.Tools;
using MAF1.Utils;
using Microsoft.Agents.AI;
using Microsoft.Extensions.AI;

namespace MAF1.Agents.Weather;

/// <summary>
/// 「按城市查天气」Agent。真正的 HTTP 查询在 WeatherTools.GetWeather，模型只负责决定调几次工具并写成中文摘要。
/// </summary>
public static class WeatherAgent
{
    public const string DefaultDescription = "按城市列表查询天气并汇总。";

    /// <summary>创建带 GetWeather 工具的 Agent。instructions 要求每个城市都调工具，禁止编造气温。</summary>
    public static AIAgent Create(
        AgentFactory factory,
        WeatherTools weatherTools,
        string name = "WeatherAgent",
        string? description = null,
        string? extraInstructions = null)
    {
        string instructions =
            """
            你负责查询天气。用户给出的每个城市都必须调用一次 GetWeather，不要编造天气。
            用中文汇总所有城市的天气。
            """;
        if (!string.IsNullOrWhiteSpace(extraInstructions))
        {
            instructions = instructions + "\n" + extraInstructions;
        }

        return factory.CreateAgent(
            name: name,
            instructions: instructions,
            description: string.IsNullOrWhiteSpace(description) ? DefaultDescription : description,
            tools: [AIFunctionFactory.Create(weatherTools.GetWeather)]);
    }

    /// <summary>需要上游把 cities 连到本节点。空列表直接抛错，避免无意义地打 LLM。</summary>
    public static async Task<AgentStepResult> RunAsync(
        AIAgent agent,
        IReadOnlyDictionary<string, object?> inputs,
        CancellationToken cancellationToken = default)
    {
        List<string> cities = AgentInputs.ReadStringList(inputs, "cities");
        if (cities.Count == 0)
        {
            throw new InvalidOperationException("输入 cities 为空。请把上一节点的 cities 连到本节点的 cities。");
        }

        AgentResponse response = await agent.RunAsync(
            $"请查询这些城市的天气：{string.Join("、", cities)}",
            cancellationToken: cancellationToken);
        return new AgentStepResult
        {
            Message = response.Text,
            Inputs = new Dictionary<string, object?> { ["cities"] = cities },
            Outputs = new Dictionary<string, object?> { ["summary"] = response.Text },
        };
    }
}