.NET: Refactor harness console to be more extensible and easy to understand with better UX

dotnet/Directory.Packages.props

@@ -136,6 +136,8 @@
     <PackageVersion Include="Microsoft.Azure.Functions.Worker.Sdk" Version="2.0.7" />
     <!-- Redis -->
     <PackageVersion Include="StackExchange.Redis" Version="2.10.1" />
+    <!-- Console UX -->
+    <PackageVersion Include="Spectre.Console" Version="0.49.1" />
     <!-- Test -->
     <PackageVersion Include="FluentAssertions" Version="8.8.0" />
     <PackageVersion Include="Microsoft.AspNetCore.TestHost" Condition="'$(TargetFramework)' == 'net8.0'" Version="8.0.22" />

dotnet/samples/02-agents/Harness/Harness_Shared_Console/Commands/ICommandHandler.cs

@@ -0,0 +1,28 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using Microsoft.Agents.AI;
+
+namespace Harness.Shared.Console.Commands;
+
+/// <summary>
+/// Handles a console command (e.g., /todos, /mode). Command handlers are checked
+/// in order before user input is sent to the agent. The first handler that
+/// accepts the input prevents further handlers from being checked.
+/// </summary>
+public interface ICommandHandler
+{
+    /// <summary>
+    /// Gets the help text for this command, displayed in the console header.
+    /// Returns <see langword="null"/> if the command is not currently available.
+    /// </summary>
+    /// <returns>Help text like <c>"/todos (show todo list)"</c>, or <see langword="null"/>.</returns>
+    string? GetHelpText();
+
+    /// <summary>
+    /// Attempts to handle the given user input.
+    /// </summary>
+    /// <param name="input">The raw user input string.</param>
+    /// <param name="session">The current agent session.</param>
+    /// <returns><see langword="true"/> if this handler handled the input; <see langword="false"/> otherwise.</returns>
+    bool TryHandle(string input, AgentSession session);
+}

dotnet/samples/02-agents/Harness/Harness_Shared_Console/Commands/ModeCommandHandler.cs

@@ -0,0 +1,69 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using Microsoft.Agents.AI;
+
+namespace Harness.Shared.Console.Commands;
+
+/// <summary>
+/// Handles the <c>/mode</c> command to display or switch the current agent mode.
+/// </summary>
+internal sealed class ModeCommandHandler : ICommandHandler
+{
+    private readonly AgentModeProvider? _modeProvider;
+    private readonly IReadOnlyDictionary<string, ConsoleColor>? _modeColors;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="ModeCommandHandler"/> class.
+    /// </summary>
+    /// <param name="modeProvider">The mode provider, or <see langword="null"/> if not available.</param>
+    /// <param name="modeColors">Optional mapping of mode names to console colors.</param>
+    public ModeCommandHandler(AgentModeProvider? modeProvider, IReadOnlyDictionary<string, ConsoleColor>? modeColors = null)
+    {
+        this._modeProvider = modeProvider;
+        this._modeColors = modeColors;
+    }
+
+    /// <inheritdoc/>
+    public string? GetHelpText() => this._modeProvider is not null ? "/mode [plan|execute] (show or switch mode)" : null;
+
+    /// <inheritdoc/>
+    public bool TryHandle(string input, AgentSession session)
+    {
+        if (!input.StartsWith("/mode ", StringComparison.OrdinalIgnoreCase) && !input.Equals("/mode", StringComparison.OrdinalIgnoreCase))
+        {
+            return false;
+        }
+
+        if (this._modeProvider is null)
+        {
+            System.Console.WriteLine("AgentModeProvider is not available.");
+            return true;
+        }
+
+        string[] parts = input.Split(' ', 2, StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries);
+        if (parts.Length < 2)
+        {
+            string current = this._modeProvider.GetMode(session);
+            System.Console.WriteLine($"\n  Current mode: {current}\n");
+            return true;
+        }
+
+        string newMode = parts[1];
+
+        try
+        {
+            this._modeProvider.SetMode(session, newMode);
+            System.Console.ForegroundColor = ConsoleWriter.GetModeColor(newMode, this._modeColors);
+            System.Console.WriteLine($"\n  Switched to {newMode} mode.\n");
+            System.Console.ResetColor();
+        }
+        catch (ArgumentException ex)
+        {
+            System.Console.ForegroundColor = ConsoleColor.Red;
+            System.Console.WriteLine($"\n  {ex}\n");
+            System.Console.ResetColor();
+        }
+
+        return true;
+    }
+}

dotnet/samples/02-agents/Harness/Harness_Shared_Console/Commands/TodoCommandHandler.cs

@@ -0,0 +1,66 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using Microsoft.Agents.AI;
+
+namespace Harness.Shared.Console.Commands;
+
+/// <summary>
+/// Handles the <c>/todos</c> command to display the current todo list.
+/// </summary>
+internal sealed class TodoCommandHandler : ICommandHandler
+{
+    private readonly TodoProvider? _todoProvider;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="TodoCommandHandler"/> class.
+    /// </summary>
+    /// <param name="todoProvider">The todo provider, or <see langword="null"/> if not available.</param>
+    public TodoCommandHandler(TodoProvider? todoProvider)
+    {
+        this._todoProvider = todoProvider;
+    }
+
+    /// <inheritdoc/>
+    public string? GetHelpText() => this._todoProvider is not null ? "/todos (show todo list)" : null;
+
+    /// <inheritdoc/>
+    public bool TryHandle(string input, AgentSession session)
+    {
+        if (!input.Equals("/todos", StringComparison.OrdinalIgnoreCase))
+        {
+            return false;
+        }
+
+        if (this._todoProvider is null)
+        {
+            System.Console.WriteLine("TodoProvider is not available.");
+            return true;
+        }
+
+        var todos = this._todoProvider.GetAllTodos(session);
+        if (todos.Count == 0)
+        {
+            System.Console.WriteLine("\n  No todos yet.\n");
+            return true;
+        }
+
+        System.Console.WriteLine();
+        System.Console.WriteLine("  ── Todo List ──");
+        foreach (var item in todos)
+        {
+            string status = item.IsComplete ? "✓" : "○";
+            System.Console.ForegroundColor = item.IsComplete ? ConsoleColor.DarkGray : ConsoleColor.White;
+            System.Console.Write($"  [{status}] #{item.Id} {item.Title}");
+            if (!string.IsNullOrWhiteSpace(item.Description))
+            {
+                System.Console.Write($" — {item.Description}");
+            }
+
+            System.Console.WriteLine();
+        }
+
+        System.Console.ResetColor();
+        System.Console.WriteLine();
+        return true;
+    }
+}