feat: add startup banner to normal TUI

pkg/leantui/banner.go

@@ -1,24 +1,10 @@
 package leantui
 
+import tuibanner "github.com/docker/docker-agent/pkg/tui/banner"
+
 const (
 	bannerTopPadding  = 1
 	bannerLeftPadding = 2
 )
 
-// bannerLines is a pre-rendered ASCII-art banner for the lean TUI welcome
-// screen. Each unpadded line fits within 56 columns.
-var bannerLines = []string{
-	`██████╗  ██████╗  ██████╗██╗  ██╗███████╗██████╗ `,
-	`██╔══██╗██╔═══██╗██╔════╝██║ ██╔╝██╔════╝██╔══██╗`,
-	`██║  ██║██║   ██║██║     █████╔╝ █████╗  ██████╔╝`,
-	`██║  ██║██║   ██║██║     ██╔═██╗ ██╔══╝  ██╔══██╗`,
-	`██████╔╝╚██████╔╝╚██████╗██║  ██╗███████╗██║  ██║`,
-	`╚═════╝  ╚═════╝  ╚═════╝╚═╝  ╚═╝╚══════╝╚═╝  ╚═╝`,
-	``,
-	`     █████╗  ██████╗ ███████╗███╗   ██╗████████╗`,
-	`    ██╔══██╗██╔════╝ ██╔════╝████╗  ██║╚══██╔══╝`,
-	`    ███████║██║  ███╗█████╗  ██╔██╗ ██║   ██║   `,
-	`    ██╔══██║██║   ██║██╔══╝  ██║╚██╗██║   ██║   `,
-	`    ██║  ██║╚██████╔╝███████╗██║ ╚████║   ██║   `,
-	`    ╚═╝  ╚═╝ ╚═════╝ ╚══════╝╚═╝  ╚═══╝   ╚═╝   `,
-}
+var bannerLines = tuibanner.Lines

pkg/tui/banner/banner.go

@@ -0,0 +1,23 @@
+package banner
+
+const (
+	Width  = 56
+	Height = 13
+)
+
+// Lines is the Docker Agent ASCII-art startup banner.
+var Lines = []string{
+	`██████╗  ██████╗  ██████╗██╗  ██╗███████╗██████╗ `,
+	`██╔══██╗██╔═══██╗██╔════╝██║ ██╔╝██╔════╝██╔══██╗`,
+	`██║  ██║██║   ██║██║     █████╔╝ █████╗  ██████╔╝`,
+	`██║  ██║██║   ██║██║     ██╔═██╗ ██╔══╝  ██╔══██╗`,
+	`██████╔╝╚██████╔╝╚██████╗██║  ██╗███████╗██║  ██║`,
+	`╚═════╝  ╚═════╝  ╚═════╝╚═╝  ╚═╝╚══════╝╚═╝  ╚═╝`,
+	``,
+	`     █████╗  ██████╗ ███████╗███╗   ██╗████████╗`,
+	`    ██╔══██╗██╔════╝ ██╔════╝████╗  ██║╚══██╔══╝`,
+	`    ███████║██║  ███╗█████╗  ██╔██╗ ██║   ██║   `,
+	`    ██╔══██║██║   ██║██╔══╝  ██║╚██╗██║   ██║   `,
+	`    ██║  ██║╚██████╔╝███████╗██║ ╚████║   ██║   `,
+	`    ╚═╝  ╚═╝ ╚═════╝ ╚══════╝╚═╝  ╚═══╝   ╚═╝   `,
+}

pkg/tui/page/chat/chat.go

@@ -15,6 +15,7 @@ import (
 	"github.com/docker/docker-agent/pkg/app"
 	"github.com/docker/docker-agent/pkg/chat"
 	"github.com/docker/docker-agent/pkg/tui/animation"
+	tuibanner "github.com/docker/docker-agent/pkg/tui/banner"
 	"github.com/docker/docker-agent/pkg/tui/commands"
 	"github.com/docker/docker-agent/pkg/tui/components/messages"
 	"github.com/docker/docker-agent/pkg/tui/components/notification"
@@ -230,6 +231,7 @@ type chatPage struct {
 	// Track whether we've received content from an assistant response
 	// Used by --exit-after-response to ensure we don't exit before receiving content
 	hasReceivedAssistantContent bool
+	showStartupBanner           bool
 
 	// Message queue for enqueuing messages while agent is working
 	messageQueue []queuedMessage
@@ -374,14 +376,15 @@ func defaultKeyMap() KeyMap {
 // New creates a new chat page
 func New(ar *animation.Runtime, ctx context.Context, a *app.App, sessionState *service.SessionState, opts ...PageOption) Page {
 	p := &chatPage{
-		ar:            ar,
-		ctx:           func() context.Context { return context.WithoutCancel(ctx) },
-		sidebar:       sidebar.New(ar, ctx, sessionState),
-		messages:      messages.New(ar, sessionState),
-		app:           a,
-		keyMap:        defaultKeyMap(),
-		commandParser: commands.NewParser(),
-		sessionState:  sessionState,
+		ar:                ar,
+		ctx:               func() context.Context { return context.WithoutCancel(ctx) },
+		sidebar:           sidebar.New(ar, ctx, sessionState),
+		messages:          messages.New(ar, sessionState),
+		app:               a,
+		keyMap:            defaultKeyMap(),
+		commandParser:     commands.NewParser(),
+		sessionState:      sessionState,
+		showStartupBanner: true,
 	}
 
 	for _, opt := range opts {
@@ -723,11 +726,30 @@ func (p *chatPage) renderCollapsedSidebar(sl sidebarLayout) string {
 		Render(sidebarWithDivider)
 }
 
+func (p *chatPage) messagesView(sl sidebarLayout) string {
+	messagesView := p.messages.View()
+	if messagesView != "" || !p.showStartupBanner {
+		return messagesView
+	}
+	if sl.chatWidth < tuibanner.Width || sl.chatHeight < tuibanner.Height {
+		return ""
+	}
+
+	banner := styles.BaseStyle.Foreground(styles.Accent).Render(strings.Join(tuibanner.Lines, "\n"))
+	return lipgloss.Place(
+		sl.chatWidth,
+		sl.chatHeight,
+		lipgloss.Center,
+		lipgloss.Center,
+		banner,
+	)
+}
+
 // View renders the chat page (messages + sidebar only, no editor or resize handle)
 func (p *chatPage) View() string {
 	sl := p.computeSidebarLayout()
 
-	messagesView := p.messages.View()
+	messagesView := p.messagesView(sl)
 
 	var bodyContent string
 

pkg/tui/page/chat/layout_position_test.go

@@ -11,6 +11,7 @@ import (
 
 	"github.com/docker/docker-agent/pkg/runtime"
 	"github.com/docker/docker-agent/pkg/tui/animation"
+	tuibanner "github.com/docker/docker-agent/pkg/tui/banner"
 	"github.com/docker/docker-agent/pkg/tui/components/messages"
 	"github.com/docker/docker-agent/pkg/tui/components/sidebar"
 	msgtypes "github.com/docker/docker-agent/pkg/tui/messages"
@@ -23,16 +24,119 @@ func newLayoutTestPage(t *testing.T, position msgtypes.SidebarPosition) *chatPag
 	t.Helper()
 	sessionState := &service.SessionState{}
 	p := &chatPage{
-		sidebar:      sidebar.New(animation.NewRuntime(), t.Context(), sessionState),
-		messages:     messages.New(animation.NewRuntime(), sessionState),
-		sessionState: sessionState,
-		width:        160,
-		height:       40,
+		sidebar:           sidebar.New(animation.NewRuntime(), t.Context(), sessionState),
+		messages:          messages.New(animation.NewRuntime(), sessionState),
+		sessionState:      sessionState,
+		width:             160,
+		height:            40,
+		showStartupBanner: true,
 	}
 	p.layoutSettings = msgtypes.LayoutSettings{SidebarPosition: position}
 	return p
 }
 
+func TestNewChatPageShowsBannerBeforeAgentInfo(t *testing.T) {
+	t.Parallel()
+
+	sessionState := &service.SessionState{}
+	p := New(animation.NewRuntime(), t.Context(), nil, sessionState).(*chatPage)
+	p.SetSize(160, 40)
+
+	assert.True(t, p.showStartupBanner)
+	assert.Contains(t, ansi.Strip(p.messagesView(p.computeSidebarLayout())), tuibanner.Lines[0])
+}
+
+func TestStartupBannerIsCenteredInEmptyChat(t *testing.T) {
+	t.Parallel()
+
+	p := newLayoutTestPage(t, msgtypes.SidebarRight)
+	p.showStartupBanner = true
+	p.SetSize(p.width, p.height)
+	sl := p.computeSidebarLayout()
+
+	lines := strings.Split(p.messagesView(sl), "\n")
+	require.Len(t, lines, sl.chatHeight)
+
+	firstBannerLine := -1
+	for i, line := range lines {
+		if strings.Contains(ansi.Strip(line), tuibanner.Lines[0]) {
+			firstBannerLine = i
+			break
+		}
+	}
+	require.NotEqual(t, -1, firstBannerLine)
+	assert.Equal(t, (sl.chatHeight-len(tuibanner.Lines))/2, firstBannerLine)
+	assert.Equal(t, (sl.chatWidth-ansi.StringWidth(tuibanner.Lines[0]))/2,
+		strings.Index(ansi.Strip(lines[firstBannerLine]), "█"))
+}
+
+func TestStartupBannerHiddenWhenChatIsTooSmall(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name   string
+		width  int
+		height int
+	}{
+		{name: "too narrow", width: tuibanner.Width - 1, height: tuibanner.Height},
+		{name: "too short", width: tuibanner.Width, height: tuibanner.Height - 1},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			p := newLayoutTestPage(t, msgtypes.SidebarRight)
+			p.showStartupBanner = true
+
+			assert.Empty(t, p.messagesView(sidebarLayout{
+				chatWidth:  tt.width,
+				chatHeight: tt.height,
+			}))
+		})
+	}
+}
+
+func TestEmptyAgentInfoDoesNotReactivateStartupBanner(t *testing.T) {
+	t.Parallel()
+
+	p := newLayoutTestPage(t, msgtypes.SidebarRight)
+	p.showStartupBanner = false
+	handled, _ := p.handleRuntimeEvent(runtime.AgentInfo("root", "model", "", ""))
+
+	require.True(t, handled)
+	assert.False(t, p.showStartupBanner)
+}
+
+func TestAgentWelcomeMessageControlsStartupBanner(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name           string
+		welcomeMessage string
+		wantBanner     bool
+	}{
+		{name: "empty welcome", wantBanner: true},
+		{name: "configured welcome", welcomeMessage: "Welcome to the agent"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			p := newLayoutTestPage(t, msgtypes.SidebarRight)
+			event := runtime.AgentInfo("root", "model", "", tt.welcomeMessage)
+			handled, _ := p.handleRuntimeEvent(event)
+
+			require.True(t, handled)
+			assert.Equal(t, tt.wantBanner, p.showStartupBanner)
+			out := ansi.Strip(p.messagesView(p.computeSidebarLayout()))
+			if tt.wantBanner {
+				assert.Contains(t, out, tuibanner.Lines[0])
+			} else {
+				assert.Contains(t, out, tt.welcomeMessage)
+				assert.NotContains(t, out, tuibanner.Lines[0])
+			}
+		})
+	}
+}
+
 func TestComputeSidebarLayout_RightDefault(t *testing.T) {
 	t.Parallel()
 

pkg/tui/page/chat/runtime_events.go

@@ -83,6 +83,7 @@ func (p *chatPage) handleRuntimeEvent(msg tea.Msg) (bool, tea.Cmd) {
 
 	// ===== Content Events =====
 	case *runtime.UserMessageEvent:
+		p.showStartupBanner = false
 		return true, p.messages.ReplaceLoadingWithUser(msg.Message, msg.SessionPosition)
 
 	case *runtime.AgentChoiceEvent:
@@ -117,6 +118,9 @@ func (p *chatPage) handleRuntimeEvent(msg tea.Msg) (bool, tea.Cmd) {
 
 	case *runtime.AgentInfoEvent:
 		sidebarCmd := p.sidebar.SetAgentInfo(msg.AgentName, msg.Model, msg.Description, msg.ContextLimit, msg.CompactionModel, msg.PrimaryContextLimit)
+		if msg.WelcomeMessage != "" {
+			p.showStartupBanner = false
+		}
 		p.messages.AddWelcomeMessage(msg.WelcomeMessage)
 		return true, sidebarCmd