How I Built a C# AI Agent That Debugs .NET Exceptions

        ChatCompletionAgent agent = new()
        {
            Name = "DotNetErrorAgent",
            Instructions =
            """
            You are a senior .NET troubleshooting expert specializing in:

                        - C#
                        - ASP.NET Core
                        - Entity Framework
                        - Azure
                        - Semantic Kernel
                        - Dependency Injection
                        - NuGet package compatibility
                        - Modern .NET applications

                        CRITICAL RULES:

                        - Always call SearchErrorSolutions before responding.
                        - Never answer only from internal knowledge.
                        - Research first using external sources.
                        - Search GitHub issues, StackOverflow, Microsoft docs and community discussions.
                        - Use search findings as evidence.

                        ANALYSIS PROCESS:

                        1. Understand the exception type
                        2. Analyze stack trace details
                        3. Identify framework and package clues
                        4. Research external findings
                        5. Determine likely causes
                        6. Rank causes by probability
                        7. Identify version compatibility issues
                        8. Suggest practical fixes
                        9. Provide corrected code
                        10. Explain why the fix works

                        WHEN INFORMATION IS INCOMPLETE:

                        - Clearly state assumptions
                        - Mention missing information
                        - Request additional context if required

                        WHEN MULTIPLE ROOT CAUSES EXIST:

                        - Rank them:
                           High probability
                           Medium probability
                           Low probability

                        RESPONSE FORMAT:

                        Exception Summary:
                        ...

                        Root Cause Analysis:
                        ...

                        Possible Causes:
                        1.
                        2.
                        3.

                        Why It Happens:
                        ...

                        Recommended Fix:
                        ...

                        Corrected Code:
                        ```

csharp
                        ...

            """,
            Kernel = kernel,
            Arguments = new KernelArguments(settings)
        };

public class WebSearchPlugin
{
    private readonly HttpClient _httpClient;
    private readonly string _apiKey;

    public WebSearchPlugin(HttpClient httpClient, IConfiguration configuration)
    {
        _httpClient = httpClient;
        _apiKey = configuration["Tavily:ApiKey"]!;
    }

    [KernelFunction]
    [Description("Searches the web for software errors, fixes, GitHub issues and troubleshooting discussions")]
    public async Task<string> SearchErrorSolutions([Description("Full exception message including stack trace")] string error)
    {
        var body = new
        {
            query =
                    $"""
                        Find solutions for:

                        {error}

                        Include:GitHub issues,StackOverflow,official docs, root causes
                        """,
            max_results = 5,
            include_answer = "advanced",
            search_depth = "advanced"
        };

        var request = new HttpRequestMessage(HttpMethod.Post, "https://api.tavily.com/search");

        request.Content = new StringContent(JsonSerializer.Serialize(body), Encoding.UTF8, "application/json");

        request.Headers.Add("Authorization", $"Bearer {_apiKey}");

        var response = await _httpClient.SendAsync(request);

        return await response.Content.ReadAsStringAsync();
    }
}

Paste your .NET exception:
System.InvalidOperationException: Unable to resolve service for type IUserService while activating UserController