feat: click on agent in sidebar to switch to it

pkg/tui/components/sidebar/sidebar.go

@@ -57,8 +57,9 @@ type Model interface {
 	LoadFromSession(sess *session.Session)
 	// HandleClick checks if click is on the star or title and returns true if handled
 	HandleClick(x, y int) bool
-	// HandleClickType returns the type of click (star, title, or none)
-	HandleClickType(x, y int) ClickResult
+	// HandleClickType returns the type of click (star, title, agent, or none).
+	// For ClickAgent, the second return value is the agent name.
+	HandleClickType(x, y int) (ClickResult, string)
 	// IsCollapsed returns whether the sidebar is collapsed
 	IsCollapsed() bool
 	// ToggleCollapsed toggles the collapsed state
@@ -147,6 +148,9 @@ type model struct {
 	cachedWidth          int      // Width used for cached render
 	cachedNeedsScrollbar bool     // Whether scrollbar is needed for cached render
 	cacheDirty           bool     // True when cache needs rebuild
+
+	// Agent click zones: maps content line index to agent name for click detection
+	agentClickZones map[int]string // content line -> agent name
 }
 
 // Option is a functional option for configuring the sidebar.
@@ -343,21 +347,24 @@ const (
 	ClickStar
 	ClickTitle      // Click on the title area (use double-click to edit)
 	ClickWorkingDir // Click on the working directory line
+	ClickAgent      // Click on an agent name in the sidebar
 )
 
 // HandleClick checks if click is on the star or title and returns true if it was
 // x and y are coordinates relative to the sidebar's top-left corner
 // This does NOT toggle the state - caller should handle that
 func (m *model) HandleClick(x, y int) bool {
-	return m.HandleClickType(x, y) != ClickNone
+	result, _ := m.HandleClickType(x, y)
+	return result != ClickNone
 }
 
-// HandleClickType returns what was clicked (star, title, working dir, or nothing)
-func (m *model) HandleClickType(x, y int) ClickResult {
+// HandleClickType returns what was clicked (star, title, working dir, agent, or nothing).
+// For ClickAgent, the second return value is the agent name.
+func (m *model) HandleClickType(x, y int) (ClickResult, string) {
 	// Account for left padding
 	adjustedX := x - m.layoutCfg.PaddingLeft
 	if adjustedX < 0 {
-		return ClickNone
+		return ClickNone, ""
 	}
 
 	if m.mode == ModeCollapsed {
@@ -368,11 +375,11 @@ func (m *model) HandleClickType(x, y int) ClickResult {
 		if y >= 0 && y < titleLines {
 			// Check if click is on the star (first line only, first few chars)
 			if y == 0 && m.sessionHasContent && adjustedX <= starClickWidth {
-				return ClickStar
+				return ClickStar, ""
 			}
 			// Click is on title area (for double-click to edit)
 			if m.titleGenerated && !m.editingTitle {
-				return ClickTitle
+				return ClickTitle, ""
 			}
 		}
 
@@ -381,10 +388,10 @@ func (m *model) HandleClickType(x, y int) ClickResult {
 		wdStartY := vm.titleSectionLines()
 		wdLines := linesNeeded(lipgloss.Width(vm.WorkingDir), vm.ContentWidth)
 		if m.workingDirectory != "" && y >= wdStartY && y < wdStartY+wdLines {
-			return ClickWorkingDir
+			return ClickWorkingDir, ""
 		}
 
-		return ClickNone
+		return ClickNone, ""
 	}
 
 	// In vertical mode, the title starts at verticalStarY
@@ -396,20 +403,25 @@ func (m *model) HandleClickType(x, y int) ClickResult {
 	if contentY >= verticalStarY && contentY < verticalStarY+titleLines {
 		// Check if click is on the star (first line only, first few chars)
 		if contentY == verticalStarY && m.sessionHasContent && adjustedX <= starClickWidth {
-			return ClickStar
+			return ClickStar, ""
 		}
 		// Click is on title area (for double-click to edit)
 		if m.titleGenerated && !m.editingTitle {
-			return ClickTitle
+			return ClickTitle, ""
 		}
 	}
 
 	// Working dir is at: verticalStarY + titleLines (title) + 1 (empty separator)
 	if m.workingDirectory != "" && contentY == verticalStarY+titleLines+1 {
-		return ClickWorkingDir
+		return ClickWorkingDir, ""
+	}
+
+	// Check if click is on an agent name
+	if agentName, ok := m.agentClickZones[contentY]; ok {
+		return ClickAgent, agentName
 	}
 
-	return ClickNone
+	return ClickNone, ""
 }
 
 // titleLineCount returns the number of lines the title occupies when rendered.
@@ -903,7 +915,12 @@ func (m *model) renderSections(contentWidth int) []string {
 	appendSection(m.sessionInfo(contentWidth))
 	appendSection(m.tokenUsage(contentWidth))
 	appendSection(m.queueSection(contentWidth))
+
+	// Track where agent entries start so we can detect clicks on agent names
+	agentSectionStart := len(lines)
 	appendSection(m.agentInfo(contentWidth))
+	m.buildAgentClickZones(agentSectionStart, lines)
+
 	appendSection(m.toolsetInfo(contentWidth))
 
 	m.todoComp.SetSize(contentWidth)
@@ -1197,6 +1214,35 @@ func (m *model) renderAgentEntry(content *strings.Builder, agent runtime.AgentDe
 	content.WriteString(toolcommon.TruncateText("Model: "+agent.Model, maxWidth))
 }
 
+// buildAgentClickZones populates agentClickZones by scanning the rendered lines
+// to find which lines belong to which agent. It relies on the structure produced
+// by renderTab + agentInfo: a 2-line tab header, then agent blocks separated by
+// visually blank lines. Each consecutive run of non-blank lines maps to the next
+// agent in order. This avoids duplicating line-count logic from renderAgentEntry.
+func (m *model) buildAgentClickZones(agentSectionStart int, lines []string) {
+	m.agentClickZones = make(map[int]string)
+	if len(m.availableAgents) == 0 {
+		return
+	}
+
+	const tabHeaderLines = 2 // tab title + TabStyle top padding
+	agentIdx := 0
+	inBlock := false
+
+	for i := agentSectionStart + tabHeaderLines; i < len(lines) && agentIdx < len(m.availableAgents); i++ {
+		if lipgloss.Width(lines[i]) == 0 {
+			// Blank line: if we were inside a block, advance to the next agent
+			if inBlock {
+				agentIdx++
+				inBlock = false
+			}
+			continue
+		}
+		inBlock = true
+		m.agentClickZones[i] = m.availableAgents[agentIdx].Name
+	}
+}
+
 // toolsetInfo renders the current toolset status information
 func (m *model) toolsetInfo(contentWidth int) string {
 	var lines []string

pkg/tui/components/sidebar/title_edit_test.go

@@ -97,7 +97,7 @@ func TestSidebar_HandleClickType(t *testing.T) {
 
 	// In vertical mode, the title line is at verticalStarY
 	// Click on the star area (adjusted x = 0-2, so raw x = 1-3)
-	result := sb.HandleClickType(paddingLeft+1, verticalStarY)
+	result, _ := sb.HandleClickType(paddingLeft+1, verticalStarY)
 	assert.Equal(t, ClickStar, result, "click on star area should return ClickStar")
 
 	// Set up a title with titleGenerated=true so ClickTitle can be returned
@@ -107,16 +107,16 @@ func TestSidebar_HandleClickType(t *testing.T) {
 	// Click anywhere on the title area (after star) should return ClickTitle
 	// Star "☆ " = 2 chars, so title area starts at position 2
 	titleX := paddingLeft + 3 // middle of title
-	result = sb.HandleClickType(titleX, verticalStarY)
+	result, _ = sb.HandleClickType(titleX, verticalStarY)
 	assert.Equal(t, ClickTitle, result, "click on title area should return ClickTitle")
 
 	// Click at the end (where pencil icon is) should also return ClickTitle
 	pencilX := paddingLeft + 4
-	result = sb.HandleClickType(pencilX, verticalStarY)
+	result, _ = sb.HandleClickType(pencilX, verticalStarY)
 	assert.Equal(t, ClickTitle, result, "click on pencil icon area should return ClickTitle")
 
 	// Click elsewhere (wrong y)
-	result = sb.HandleClickType(10, 0)
+	result, _ = sb.HandleClickType(10, 0)
 	assert.Equal(t, ClickNone, result, "click elsewhere should return ClickNone")
 }
 
@@ -173,15 +173,15 @@ func TestSidebar_HandleClickType_WrappedTitle_Collapsed(t *testing.T) {
 	assert.Greater(t, titleLines, 1, "title should wrap to multiple lines")
 
 	// Click on line 0 (first title line) after star should return ClickTitle
-	result := sb.HandleClickType(paddingLeft+3, 0)
+	result, _ := sb.HandleClickType(paddingLeft+3, 0)
 	assert.Equal(t, ClickTitle, result, "click on first title line should return ClickTitle")
 
 	// Click on line 1 (wrapped title line) should also return ClickTitle
-	result = sb.HandleClickType(paddingLeft+1, 1)
+	result, _ = sb.HandleClickType(paddingLeft+1, 1)
 	assert.Equal(t, ClickTitle, result, "click on wrapped title line should return ClickTitle")
 
 	// Star should still be clickable on line 0
-	result = sb.HandleClickType(paddingLeft+1, 0)
+	result, _ = sb.HandleClickType(paddingLeft+1, 0)
 	assert.Equal(t, ClickStar, result, "star should still be clickable on line 0")
 }
 
@@ -211,15 +211,15 @@ func TestSidebar_HandleClickType_WrappedTitle_Vertical(t *testing.T) {
 
 	// In vertical mode, title starts at verticalStarY
 	// Click on verticalStarY (first title line) after star should return ClickTitle
-	result := sb.HandleClickType(paddingLeft+3, verticalStarY)
+	result, _ := sb.HandleClickType(paddingLeft+3, verticalStarY)
 	assert.Equal(t, ClickTitle, result, "click on first title line should return ClickTitle")
 
 	// Click on verticalStarY+1 (wrapped title line) should also return ClickTitle
-	result = sb.HandleClickType(paddingLeft+1, verticalStarY+1)
+	result, _ = sb.HandleClickType(paddingLeft+1, verticalStarY+1)
 	assert.Equal(t, ClickTitle, result, "click on wrapped title line should return ClickTitle")
 
 	// Star should still be clickable on verticalStarY
-	result = sb.HandleClickType(paddingLeft+1, verticalStarY)
+	result, _ = sb.HandleClickType(paddingLeft+1, verticalStarY)
 	assert.Equal(t, ClickStar, result, "star should still be clickable on verticalStarY")
 }
 
@@ -248,11 +248,11 @@ func TestSidebar_HandleClickType_NoWrap(t *testing.T) {
 	assert.Equal(t, 1, titleLines, "title should be on single line when it doesn't wrap")
 
 	// Click on the title area should return ClickTitle
-	result := sb.HandleClickType(paddingLeft+3, verticalStarY)
+	result, _ := sb.HandleClickType(paddingLeft+3, verticalStarY)
 	assert.Equal(t, ClickTitle, result, "click on title should return ClickTitle")
 
 	// Star should still be clickable
-	result = sb.HandleClickType(paddingLeft+1, verticalStarY)
+	result, _ = sb.HandleClickType(paddingLeft+1, verticalStarY)
 	assert.Equal(t, ClickStar, result, "star should still be clickable")
 }
 
@@ -278,15 +278,15 @@ func TestSidebar_HandleClickType_WorkingDir_Vertical(t *testing.T) {
 	wdY := verticalStarY + titleLines + 1
 
 	// Click on the working directory line
-	result := sb.HandleClickType(paddingLeft+3, wdY)
+	result, _ := sb.HandleClickType(paddingLeft+3, wdY)
 	assert.Equal(t, ClickWorkingDir, result, "click on working dir line should return ClickWorkingDir")
 
 	// Click on the title line should still return ClickTitle
-	result = sb.HandleClickType(paddingLeft+3, verticalStarY)
+	result, _ = sb.HandleClickType(paddingLeft+3, verticalStarY)
 	assert.Equal(t, ClickTitle, result, "click on title should still return ClickTitle")
 
 	// Click on the empty separator line should return ClickNone
-	result = sb.HandleClickType(paddingLeft+3, verticalStarY+titleLines)
+	result, _ = sb.HandleClickType(paddingLeft+3, verticalStarY+titleLines)
 	assert.Equal(t, ClickNone, result, "click on separator line should return ClickNone")
 }
 
@@ -312,11 +312,11 @@ func TestSidebar_HandleClickType_WorkingDir_Collapsed(t *testing.T) {
 	assert.Equal(t, 1, titleLines, "title should be on single line")
 
 	// Click on the working directory line (right after title)
-	result := sb.HandleClickType(paddingLeft+3, titleLines)
+	result, _ := sb.HandleClickType(paddingLeft+3, titleLines)
 	assert.Equal(t, ClickWorkingDir, result, "click on working dir line should return ClickWorkingDir")
 
 	// Click on the title should still return ClickTitle
-	result = sb.HandleClickType(paddingLeft+3, 0)
+	result, _ = sb.HandleClickType(paddingLeft+3, 0)
 	assert.Equal(t, ClickTitle, result, "click on title should still return ClickTitle")
 }
 

pkg/tui/page/chat/chat.go

@@ -954,8 +954,8 @@ func (p *chatPage) SetSidebarSettings(settings SidebarSettings) {
 }
 
 // handleSidebarClickType checks what was clicked in the sidebar area.
-// Returns the type of click (star, title, working dir, or none).
-func (p *chatPage) handleSidebarClickType(x, y int) sidebar.ClickResult {
+// Returns the click type and, for ClickAgent, the agent name.
+func (p *chatPage) handleSidebarClickType(x, y int) (sidebar.ClickResult, string) {
 	adjustedX := x - styles.AppPadding
 	sl := p.computeSidebarLayout()
 
@@ -968,7 +968,7 @@ func (p *chatPage) handleSidebarClickType(x, y int) sidebar.ClickResult {
 		}
 	}
 
-	return sidebar.ClickNone
+	return sidebar.ClickNone, ""
 }
 
 // routeMouseEvent routes mouse events to the appropriate component based on coordinates.

pkg/tui/page/chat/hittest.go

@@ -17,6 +17,7 @@ const (
 	TargetSidebarStar
 	TargetSidebarTitle
 	TargetSidebarWorkingDir
+	TargetSidebarAgent
 	TargetSidebarContent
 	TargetMessages
 )
@@ -25,7 +26,8 @@ const (
 // This centralizes all hit-testing logic in one place, making it easier
 // to understand the clickable regions and their priorities.
 type HitTest struct {
-	page *chatPage
+	page      *chatPage
+	AgentName string // populated when At() returns TargetSidebarAgent
 }
 
 // NewHitTest creates a hit tester for the given chat page.
@@ -119,14 +121,17 @@ func ExtractCoords(msg tea.Msg) (x, y int, ok bool) {
 
 // sidebarClickTarget determines the specific target within the sidebar area.
 func (h *HitTest) sidebarClickTarget(x, y int) MouseTarget {
-	clickResult := h.page.handleSidebarClickType(x, y)
+	clickResult, agentName := h.page.handleSidebarClickType(x, y)
 	switch clickResult {
 	case sidebar.ClickStar:
 		return TargetSidebarStar
 	case sidebar.ClickTitle:
 		return TargetSidebarTitle
 	case sidebar.ClickWorkingDir:
 		return TargetSidebarWorkingDir
+	case sidebar.ClickAgent:
+		h.AgentName = agentName
+		return TargetSidebarAgent
 	default:
 		return TargetSidebarContent
 	}

pkg/tui/page/chat/input_handlers.go

@@ -148,6 +148,14 @@ func (p *chatPage) handleMouseClick(msg tea.MouseClickMsg) (layout.Model, tea.Cm
 			return p, copyWorkingDirToClipboard(p.sidebar.WorkingDirectory())
 		}
 
+	case TargetSidebarAgent:
+		if msg.Button == tea.MouseLeft {
+			if hit.AgentName != "" {
+				return p, core.CmdHandler(msgtypes.SwitchAgentMsg{AgentName: hit.AgentName})
+			}
+			return p, nil
+		}
+
 	case TargetMessages:
 		if !p.messages.IsMouseOnScrollbar(msg.X, msg.Y) {
 			cmd := p.routeMouseEvent(msg, msg.Y)