CopilotSidebar

Drop-in collapsible sidebar chat that wraps your main content.


using System.ClientModel;using System.Net.Http;using System.Text.Json.Serialization;using Microsoft.Agents.AI.Hosting.AGUI.AspNetCore;using Microsoft.AspNetCore.Http.Json;using Microsoft.Extensions.Options;using OpenAI;var builder = WebApplication.CreateBuilder(args);builder.Services.ConfigureHttpJsonOptions(options =>{    // Beautiful-chat types (shipped) + the full-column Sales/Flight/parity types    // ported by the family slots. Both source-generated contexts are chained so    // every feature agent's tool I/O serializes through the fast path.    options.SerializerOptions.TypeInfoResolverChain.Add(BeautifulChatSerializerContext.Default);    options.SerializerOptions.TypeInfoResolverChain.Add(SalesAgentSerializerContext.Default);    // Serialize enum types as their member-name strings rather than numeric    // ordinals (matches the Framework column's wire format).    options.SerializerOptions.Converters.Add(new JsonStringEnumConverter());});builder.Services.AddAGUI();// STOPGAP: IHttpContextAccessor lets AimockHeaderPolicy read the current// request's forwarded x-* headers (stashed on HttpContext.Items by// AimockHeaderMiddleware) at outbound-LLM-call time. HttpContext flows across// the AG-UI SSE-pump ExecutionContext boundary, unlike a middleware-set// AsyncLocal. TODO(copilotkit-sdk-dotnet): migrate to SDK-level header propagation.builder.Services.AddHttpContextAccessor();var app = builder.Build();// STOPGAP: seed the static accessor the outbound header-forwarding policy reads// (the policy is created without DI, mirroring CvDiag.Logger).AimockHeaderPolicy.HttpContextAccessor = app.Services.GetRequiredService<IHttpContextAccessor>();// Forward D5/aimock x-* headers from incoming AG-UI requests to outgoing// OpenAI calls until the .NET SDK owns this propagation centrally.app.UseMiddleware<AimockHeaderMiddleware>();// CVDIAG: backend flap-observability emitter (plan unit L1-F; spec §3). OFF by// default (CVDIAG_BACKEND_EMITTER=on to arm). Seed the static singleton the// outbound LLM policy reads (created without DI), then register the// request-pipeline instrumentation AFTER AimockHeaderMiddleware so the forwarded// x-* correlation headers are already captured for this request.CvdiagBackend.Instance = new CvdiagBackend();app.UseMiddleware<CvdiagInstrumentationMiddleware>();var loggerFactory = app.Services.GetRequiredService<ILoggerFactory>();// CVDIAG: seed the static logger used by AimockHeaderPolicy (created without DI)// to emit the outbound-LLM header-forwarding breadcrumb.CvDiag.Logger = loggerFactory.CreateLogger("CvDiag");var jsonOptions = app.Services.GetRequiredService<IOptions<JsonOptions>>().Value.SerializerOptions;// Single shared OpenAIClient for the whole column. Built once via the harness// ApiKeyResolver (env OPENAI_API_KEY -> config OPENAI_API_KEY -> GitHubToken,// fail-fast for non-mock endpoints) so EVERY feature agent hits the same// upstream with the same credential resolution — no per-feature GitHubToken// dance. Threaded into each feature factory's ctor. See the W0 contract §1.var openAiClient = CreateOpenAiClient(builder.Configuration, loggerFactory.CreateLogger("Program"));// ── Root agentic-chat agent (the Sales pipeline agent) ──────────────────────// agentic-chat, chat-slots, chat-customization-css, prebuilt-{sidebar,popup},// frontend-tools{,-async}, headless-simple, shared-state-read, and the two// tool-rendering catch-all demos all proxy to this root agent via the shared// Next.js `copilotkit/` runtime route.var salesFactory = new SalesAgentFactory(builder.Configuration, openAiClient, jsonOptions, loggerFactory);app.MapAGUI("/", salesFactory.CreateSalesAgent());// ── D5 parity agents (one factory hosts the parity-feature surface) ─────────var d5ParityFactory = new D5ParityAgentFactory(openAiClient, loggerFactory, jsonOptions);app.MapAGUI("/headless-complete", d5ParityFactory.CreateHeadlessCompleteAgent());app.MapAGUI("/voice", d5ParityFactory.CreateVoiceAgent());app.MapAGUI("/gen-ui-agent", d5ParityFactory.CreateGenUiAgent());app.MapAGUI("/gen-ui-tool-based", d5ParityFactory.CreateGenUiToolBasedAgent());app.MapAGUI("/shared-state-streaming", d5ParityFactory.CreateSharedStateStreamingAgent());app.MapAGUI("/readonly-state-agent-context", d5ParityFactory.CreateReadonlyStateAgentContext());app.MapAGUI("/tool-rendering", d5ParityFactory.CreateToolRenderingAgent(reasoning: false));app.MapAGUI("/tool-rendering-reasoning-chain", d5ParityFactory.CreateToolRenderingAgent(reasoning: true));// ── Interrupt agent (NOT-SUPPORTED, wired for parity) ───────────────────────// gen-ui-interrupt and interrupt-headless share this single backend; the// differentiation is on the frontend (in-chat picker vs. headless button grid).// Marked not_supported in manifest.yaml (skipped-incapable) pending a// @copilotkit/react-core resume-path fix — wired here so the column is 1:1.var interruptFactory = new InterruptAgentFactory(builder.Configuration, openAiClient, loggerFactory, jsonOptions);app.MapAGUI("/interrupt-adapted", interruptFactory.CreateInterruptAgent());// ── Multimodal (raw MapPost — the AG-UI adapter rejects content arrays) ─────// Parses the request body directly and emits the small AG-UI SSE event subset// the chat UI needs for text streaming over a vision-capable chat client.app.MapPost("/multimodal", (HttpContext context) => MultimodalEndpoint.HandleAsync(    context,    salesFactory.CreateMultimodalChatClient(),    loggerFactory.CreateLogger("MultimodalEndpoint")));// ── Beautiful Chat flagship demo (shipped) ──────────────────────────────────var beautifulChatFactory = new BeautifulChatAgentFactory(    builder.Configuration,    openAiClient,    jsonOptions,    loggerFactory.CreateLogger<BeautifulChatAgentFactory>());app.MapAGUI("/beautiful-chat", beautifulChatFactory.Create());// ── Agent Config (wraps a neutral inner agent in AgentConfigAgent) ──────────app.MapAGUI("/agent-config", salesFactory.CreateAgentConfigAgent());// ── Reasoning (reasoning-default + reasoning-custom share this backend) ─────app.MapAGUI("/reasoning", salesFactory.CreateReasoningAgent());// ── Declarative Gen UI (A2UI canonical BYOC) ────────────────────────────────var declarativeGenUiAgent = new DeclarativeGenUiAgent(builder.Configuration, openAiClient, loggerFactory, jsonOptions);app.MapAGUI("/declarative-gen-ui", declarativeGenUiAgent.Create());// ── A2UI fixed-schema demo ──────────────────────────────────────────────────var a2uiFixedSchemaAgent = new A2uiFixedSchemaAgent(builder.Configuration, openAiClient, loggerFactory, jsonOptions);app.MapAGUI("/a2ui-fixed-schema", a2uiFixedSchemaAgent.Create());// ── Open Generative UI — basic + advanced ───────────────────────────────────var openGenUiFactory = new OpenGenUiAgentFactory(openAiClient);app.MapAGUI("/open-gen-ui", openGenUiFactory.CreateAgent());var openGenUiAdvancedFactory = new OpenGenUiAdvancedAgentFactory(openAiClient);app.MapAGUI("/open-gen-ui-advanced", openGenUiAdvancedFactory.CreateAgent());// ── BYOC demos (hashbrown + json-render) ────────────────────────────────────var byocHashbrownFactory = new ByocHashbrownAgentFactory(openAiClient, loggerFactory);app.MapAGUI("/byoc-hashbrown", byocHashbrownFactory.CreateAgent());var byocJsonRenderFactory = new ByocJsonRenderAgentFactory(openAiClient, loggerFactory);app.MapAGUI("/byoc-json-render", byocJsonRenderFactory.CreateAgent());// ── MCP Apps demo ───────────────────────────────────────────────────────────var mcpAppsFactory = new McpAppsAgentFactory(openAiClient, loggerFactory);app.MapAGUI("/mcp-apps", mcpAppsFactory.CreateMcpAppsAgent());// ── In-app HITL demo (frontend tools + async HITL) ──────────────────────────var hitlInAppFactory = new HitlInAppAgentFactory(openAiClient, loggerFactory);app.MapAGUI("/hitl-in-app", hitlInAppFactory.CreateHitlInAppAgent());// ── In-chat HITL demo (useHumanInTheLoop) ───────────────────────────────────var hitlInChatFactory = new HitlInChatAgentFactory(openAiClient, loggerFactory);app.MapAGUI("/hitl-in-chat", hitlInChatFactory.CreateHitlInChatAgent());// ── Shared State (Read + Write) demo ────────────────────────────────────────var sharedStateReadWriteFactory = new SharedStateReadWriteAgentFactory(openAiClient, loggerFactory, jsonOptions);app.MapAGUI("/shared-state-read-write", sharedStateReadWriteFactory.CreateAgent());// ── Sub-Agents demo (supervisor delegates to research/writing/critique) ─────var subagentsFactory = new SubagentsAgentFactory(openAiClient, loggerFactory, jsonOptions);app.MapAGUI("/subagents", subagentsFactory.CreateAgent());app.MapGet("/health", () => Results.Ok(new { status = "ok" }));await app.RunAsync();static OpenAIClient CreateOpenAiClient(IConfiguration configuration, ILogger logger){    // Use the shared resolver so the primary OpenAI client and the secondary    // tool-calling HTTP client (A2uiSecondaryToolCaller) agree on which upstream    // endpoint to hit (see ApiKeyResolver for the env/config precedence and the    // non-mock fail-fast).    var endpoint = ApiKeyResolver.ResolveEndpoint(configuration);    var endpointEnv = Environment.GetEnvironmentVariable("OPENAI_BASE_URL");    var endpointConfig = configuration["OPENAI_BASE_URL"];    if (!string.IsNullOrEmpty(endpointEnv))    {        logger.LogInformation("Using OpenAI endpoint from OPENAI_BASE_URL env: {Endpoint}", endpoint);    }    else if (!string.IsNullOrEmpty(endpointConfig))    {        logger.LogInformation("Using OpenAI endpoint from configuration OPENAI_BASE_URL: {Endpoint}", endpoint);    }    else    {        logger.LogInformation("OPENAI_BASE_URL not set; using default OpenAI endpoint: {Endpoint}", endpoint);    }    var apiKey = ApiKeyResolver.ResolveApiKey(configuration, logger);    return new OpenAIClient(        new ApiKeyCredential(apiKey),        AimockHeaderPolicy.CreateOpenAIClientOptions(endpoint));}public class WeatherInfo{    [JsonPropertyName("temperature")]    public int Temperature { get; init; }    [JsonPropertyName("conditions")]    public string Conditions { get; init; } = string.Empty;    [JsonPropertyName("humidity")]    public int Humidity { get; init; }    [JsonPropertyName("wind_speed")]    public int WindSpeed { get; init; }    [JsonPropertyName("feels_like")]    public int FeelsLike { get; init; }    [JsonPropertyName("city")]    public string City { get; init; } = string.Empty;}public partial class Program { }[JsonSerializable(typeof(WeatherInfo))][JsonSerializable(typeof(BeautifulChatTodo))][JsonSerializable(typeof(List<BeautifulChatTodo>))][JsonSerializable(typeof(BeautifulChatFlight))][JsonSerializable(typeof(List<BeautifulChatFlight>))]internal partial class BeautifulChatSerializerContext : JsonSerializerContext{}

What is this?#

<CopilotSidebar> is a prebuilt chat surface that docks to the side of your app. It wraps your main content so the chat can slide out on demand, making it a good fit for in-app copilots that need to stay accessible without taking over the entire viewport.

When should I use this?#

Use the sidebar when you want:

  • A persistent, collapsible chat attached to your app shell
  • Chat to live alongside your main content rather than on top of it
  • A launcher the user can toggle without losing their place

For a floating bubble that overlays content, see CopilotPopup. For a fully embedded chat pane, use <CopilotChat> directly.

Basic setup#

Wrap your app in <CopilotKit> once (it wires the runtime, session, and agent registry) and drop <CopilotSidebar> alongside your main content. The sidebar renders as a sibling so it can slide out without reflowing your page:

page.tsx
    <CopilotKit runtimeUrl="/api/copilotkit" agent="prebuilt-sidebar">      <MainContent />      <CopilotSidebar agentId="prebuilt-sidebar" defaultOpen={true} />      <Suggestions />    </CopilotKit>

Configuring the sidebar#

<CopilotSidebar> accepts the same props as <CopilotChat> plus a few of its own. The example below opens the sidebar by default and targets a named agent:

page.tsx
      <CopilotSidebar agentId="prebuilt-sidebar" defaultOpen={true} />

Common sidebar-specific props:

PropDescription
defaultOpenWhether the sidebar starts open on first render.
agentIdAgent slug the sidebar should talk to (must match an agent configured on the runtime).
labelsUser-facing copy for the header, placeholder, and disclaimer.
headerSlot for the sidebar header bar — see the slot system.
toggleButtonSlot for the open/close launcher button.

Styling#

CopilotSidebar participates in the slot system, so every piece of its UI is customizable, from Tailwind classes on the message view to a full component swap for the header or toggle button. See custom look and feel for the full slot reference.