diff --git a/Luna.Clients.Cli/ChatClientService.cs b/Luna.Clients.Cli/ChatClientService.cs
new file mode 100644
index 0000000..6bb9ebe
--- /dev/null
+++ b/Luna.Clients.Cli/ChatClientService.cs
@@ -0,0 +1,213 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using System.Threading.Channels;
+using Luna.Shared;
+using Microsoft.AspNetCore.SignalR.Client;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+
+namespace Luna.Cli;
+
+public class ChatClientService(IHostApplicationLifetime lifetime) : IHostedService
+{
+    private HubConnection? connection;
+    private readonly Guid conversationId = Guid.NewGuid();
+    private Channel<ChatStreamUpdate>? responseChannel;
+
+    public async Task StartAsync(CancellationToken cancellationToken)
+    {
+        var serverUrl = Environment.GetEnvironmentVariable("LUNA_SERVER_URL") ?? "http://localhost:5000";
+        var hubUrl = $"{serverUrl.TrimEnd('/')}/chat";
+
+        connection = new HubConnectionBuilder()
+            .WithUrl(hubUrl)
+            .WithAutomaticReconnect()
+            .AddJsonProtocol(options =>
+            {
+                options.PayloadSerializerOptions.Converters.Add(
+                    new System.Text.Json.Serialization.JsonStringEnumConverter(System.Text.Json.JsonNamingPolicy.CamelCase));
+            })
+            .Build();
+
+        connection.On<ChatStreamUpdate>("OnMessageStreamReceived", update =>
+        {
+            responseChannel?.Writer.TryWrite(update);
+
+            if (update.IsComplete)
+                responseChannel?.Writer.TryComplete();
+        });
+
+        connection.Closed += error =>
+        {
+            Console.WriteLine(error != null
+                ? $"[connection closed: {error.Message}]"
+                : "[connection closed]");
+            responseChannel?.Writer.TryComplete(error);
+            return Task.CompletedTask;
+        };
+
+        connection.Reconnecting += error =>
+        {
+            Console.WriteLine($"[reconnecting... {error?.Message}]");
+            responseChannel?.Writer.TryComplete(error);
+            return Task.CompletedTask;
+        };
+
+        connection.Reconnected += connectionId =>
+        {
+            Console.WriteLine($"[reconnected: {connectionId}]");
+            return Task.CompletedTask;
+        };
+
+        try
+        {
+            await connection.StartAsync(cancellationToken);
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"[failed to connect to {hubUrl}: {ex.Message}]");
+            lifetime.StopApplication();
+            return;
+        }
+
+        // Print startup banner
+        Console.WriteLine("=== Luna CLI ===");
+        Console.WriteLine($"Connected to {hubUrl}");
+        Console.WriteLine("Type messages and press Enter to send.");
+        Console.WriteLine("Commands: /exit (quit), /clear (clear screen)");
+        Console.WriteLine();
+
+        // Start input loop in background
+        _ = Task.Run(() => InputLoopAsync(lifetime.ApplicationStopping), lifetime.ApplicationStopping);
+    }
+
+    private async Task InputLoopAsync(CancellationToken cancellationToken)
+    {
+        while (!cancellationToken.IsCancellationRequested)
+        {
+            try
+            {
+                Console.ForegroundColor = ConsoleColor.Green;
+                Console.Write("you> ");
+                Console.ResetColor();
+
+                var input = await Task.Run(() => Console.ReadLine(), cancellationToken);
+
+                if (input is null || string.Equals(input.Trim(), "/exit", StringComparison.OrdinalIgnoreCase))
+                {
+                    lifetime.StopApplication();
+                    break;
+                }
+
+                if (string.Equals(input.Trim(), "/clear", StringComparison.OrdinalIgnoreCase))
+                {
+                    Console.Clear();
+                    continue;
+                }
+
+                if (string.IsNullOrWhiteSpace(input))
+                {
+                    continue;
+                }
+
+                var message = new ChannelMessage(
+                    MessageId: Guid.NewGuid().ToString(),
+                    ConversationId: conversationId.ToString(),
+                    SenderId: "cli-user",
+                    SenderName: "User",
+                    Content: input.Trim(),
+                    Timestamp: DateTimeOffset.UtcNow
+                );
+
+                await StreamResponseAsync(message, cancellationToken);
+            }
+            catch (OperationCanceledException)
+            {
+                break;
+            }
+            catch (Exception ex)
+            {
+                Console.WriteLine($"[error] {ex.Message}");
+            }
+        }
+    }
+
+    private async Task StreamResponseAsync(ChannelMessage message, CancellationToken cancellationToken)
+    {
+        if (connection is null) return;
+
+        responseChannel = Channel.CreateUnbounded<ChatStreamUpdate>();
+
+        var assistantLabelPrinted = false;
+        var thinkingLabelPrinted = false;
+
+        try
+        {
+            await connection.InvokeAsync("OnMessageReceived", message, cancellationToken);
+
+            await foreach (var update in responseChannel.Reader.ReadAllAsync(cancellationToken))
+            {
+                if (update.IsComplete)
+                {
+                    if (assistantLabelPrinted || thinkingLabelPrinted)
+                        Console.WriteLine();
+                    break;
+                }
+
+                switch (update.Type)
+                {
+                    case ChatStreamUpdateType.Thinking:
+                        if (!thinkingLabelPrinted)
+                        {
+                            Console.ForegroundColor = ConsoleColor.DarkGray;
+                            Console.Write("thinking> ");
+                            Console.ResetColor();
+                            thinkingLabelPrinted = true;
+                        }
+                        if (update.Content != null)
+                        {
+                            Console.ForegroundColor = ConsoleColor.DarkGray;
+                            Console.Write(update.Content);
+                            Console.ResetColor();
+                        }
+                        break;
+
+                    case ChatStreamUpdateType.Text:
+                        if (!assistantLabelPrinted)
+                        {
+                            Console.ForegroundColor = ConsoleColor.Magenta;
+                            Console.Write("assistant> ");
+                            Console.ResetColor();
+                            assistantLabelPrinted = true;
+                        }
+                        Console.Write(update.Content);
+                        break;
+                    case ChatStreamUpdateType.Usage:
+                        Console.WriteLine($"\n[{update.Type.ToString().ToLower()}: {update.Content}]");
+                        break;
+                }
+            }
+
+            // Ensure newline if stream ended without IsComplete flag
+            if (assistantLabelPrinted || thinkingLabelPrinted)
+                Console.WriteLine();
+        }
+        catch (OperationCanceledException)
+        {
+            Console.WriteLine();
+        }
+        catch (Exception ex)
+        {
+            Console.WriteLine($"\n[stream error] {ex.Message}");
+        }
+    }
+
+    public async Task StopAsync(CancellationToken cancellationToken)
+    {
+        if (connection != null)
+        {
+            await connection.DisposeAsync();
+            connection = null;
+        }
+    }
+}
diff --git a/Luna.Clients.Cli/Luna.Clients.Cli.csproj b/Luna.Clients.Cli/Luna.Clients.Cli.csproj
new file mode 100644
index 0000000..ee0b870
--- /dev/null
+++ b/Luna.Clients.Cli/Luna.Clients.Cli.csproj
@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <RootNamespace>Luna.Cli</RootNamespace>
+  </PropertyGroup>
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.SignalR.Client" Version="10.0.4" />
+    <PackageReference Include="Microsoft.AspNetCore.SignalR.Protocols.Json" Version="10.0.5" />
+    <PackageReference Include="Microsoft.Extensions.Hosting" Version="10.0.5" />
+    <PackageReference Include="Microsoft.Extensions.Logging" Version="10.0.5" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\Luna.Shared\Luna.Shared.csproj" />
+  </ItemGroup>
+</Project>
diff --git a/Luna.Clients.Cli/Program.cs b/Luna.Clients.Cli/Program.cs
new file mode 100644
index 0000000..350fb38
--- /dev/null
+++ b/Luna.Clients.Cli/Program.cs
@@ -0,0 +1,9 @@
+using Luna.Cli;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
+using Microsoft.Extensions.Logging;
+
+var builder = Host.CreateApplicationBuilder(args);
+builder.Logging.ClearProviders();
+builder.Services.AddHostedService<ChatClientService>();
+await builder.Build().RunAsync();