fix(tui): plan mode reachable (/plan, PLAN badge, --plan-mode), @bare-name completion, matching question-box borders, bubble width/tabs (#1407)

cmd/harnesscli/main.go

@@ -176,7 +176,7 @@ func run(args []string) int {
 	workspacePath := resolveWorkspacePath(*workspace)
 
 	if *enableTUI {
-		if err := runTUI(*baseURL, workspacePath, *resume); err != nil {
+		if err := runTUI(*baseURL, workspacePath, *resume, *planMode); err != nil {
 			fmt.Fprintf(stderr, "harnesscli: tui: %v\n", err)
 			return exitClientError
 		}
@@ -571,11 +571,12 @@ func newTUIConfig(baseURL, workspace, resumeConversationID string) tui.TUIConfig
 	}
 }
 
-func runTUI(baseURL, workspace, resumeConversationID string) error {
+func runTUI(baseURL, workspace, resumeConversationID string, planMode bool) error {
 	if !term.IsTerminal(int(os.Stdout.Fd())) {
 		return fmt.Errorf("--tui requires a terminal; pipe output or use without --tui for streaming mode")
 	}
 	tuiCfg := newTUIConfig(baseURL, workspace, resumeConversationID)
+	tuiCfg.PlanMode = planMode
 	// Resolve and apply the color profile to the renderer before building the
 	// model, and store the effective profile back for accurate display.
 	tuiCfg.ColorProfile = tui.ApplyColorProfile(tuiCfg.ColorProfile)

cmd/harnesscli/main_tui_test.go

@@ -13,7 +13,7 @@ func TestRunTUIRequiresTerminal(t *testing.T) {
 		t.Skip("stdout is a terminal in this environment")
 	}
 
-	err := runTUI("http://localhost:8080", "/tmp/project", "")
+	err := runTUI("http://localhost:8080", "/tmp/project", "", false)
 	if err == nil {
 		t.Fatal("expected non-terminal runTUI call to fail")
 	}

cmd/harnesscli/tui/askuser.go

@@ -8,6 +8,7 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"github.com/charmbracelet/lipgloss"
 	"net/http"
 	"net/url"
 	"strings"
@@ -232,7 +233,7 @@ func (m Model) renderAskUserOverlay() []string {
 	q := m.askUser.questions[m.askUser.qIdx]
 	lines := []string{
 		"",
-		"┌─ " + q.Header + " ─────────────────────────────────",
+		"┌─ " + q.Header + " ",
 		"│  " + q.Question,
 		"│",
 	}
@@ -257,7 +258,22 @@ func (m Model) renderAskUserOverlay() []string {
 			lines = append(lines, "│  Deadline: expired")
 		}
 	}
-	lines = append(lines, "└────────────────────────────────────────")
+	// Size the top and bottom borders to the widest line so the box reads as
+	// one shape instead of two mismatched rules (#1407).
+	width := 0
+	for _, l := range lines {
+		if w := lipgloss.Width(l); w > width {
+			width = w
+		}
+	}
+	width += 2
+	for i, l := range lines {
+		if strings.HasPrefix(l, "┌") {
+			lines[i] = l + strings.Repeat("─", width-lipgloss.Width(l))
+			break
+		}
+	}
+	lines = append(lines, "└"+strings.Repeat("─", width-1))
 	lines = append(lines, "")
 	return lines
 }

cmd/harnesscli/tui/askuser_test.go

@@ -8,6 +8,7 @@ package tui_test
 import (
 	"encoding/json"
 	"fmt"
+	"github.com/charmbracelet/lipgloss"
 	"net/http"
 	"net/http/httptest"
 	"strings"
@@ -712,3 +713,35 @@ func activateAskUserPending(
 	next, _ = model.Update(pending)
 	return next.(tui.Model)
 }
+
+// Issue #1407: the question box's top and bottom borders must be the same
+// width so it reads as one box.
+func TestAskUser_Overlay_BordersMatch(t *testing.T) {
+	m := initModel(t, 80, 24)
+	m = m.WithCancelRun(func() {})
+	m2, _ := m.Update(tui.RunStartedMsg{RunID: "run-border-1"})
+	model := m2.(tui.Model)
+	pending := tui.AskUserPendingMsg{
+		RunID: "run-border-1", CallID: "call-b1",
+		Questions: []tui.AskUserQuestion{{Question: "Which framework should I use?", Header: "Framework",
+			Options: []tui.AskUserOption{{Label: "net/http", Description: "standard library"}, {Label: "gin", Description: "gin-gonic router"}}}},
+		DeadlineAt: time.Now().Add(5 * time.Minute),
+	}
+	model = activateAskUserPending(t, model, pending, 1)
+	var top, bottom string
+	for _, line := range strings.Split(model.View(), "\n") {
+		trimmed := strings.TrimRight(line, " ")
+		if strings.HasPrefix(trimmed, "┌") {
+			top = trimmed
+		}
+		if strings.HasPrefix(trimmed, "└") {
+			bottom = trimmed
+		}
+	}
+	if top == "" || bottom == "" {
+		t.Fatalf("question box borders not found:\n%s", model.View())
+	}
+	if lipgloss.Width(top) != lipgloss.Width(bottom) {
+		t.Fatalf("border widths differ: top %d vs bottom %d\n%s\n%s", lipgloss.Width(top), lipgloss.Width(bottom), top, bottom)
+	}
+}

cmd/harnesscli/tui/cmd_parser.go

@@ -81,6 +81,14 @@ func newEmptyCommandRegistry() *CommandRegistry {
 func builtinCommandEntries() []CommandEntry {
 	entries := []CommandEntry{
 		{Name: "plugins", Description: "Browse installed plugin bundles", Handler: func(Command) CommandResult { return CommandResult{Status: CmdOK} }, Execute: executePluginsCommand},
+		{
+			Name:        "plan",
+			Description: "Toggle plan mode: the agent plans in .harness/plan.md and waits for your approval before editing",
+			Handler: func(cmd Command) CommandResult {
+				return CommandResult{Status: CmdOK}
+			},
+			Execute: executePlanCommand,
+		},
 		{
 			Name:        "clear",
 			Description: "Clear conversation history",

cmd/harnesscli/tui/cmd_parser_test.go

@@ -396,6 +396,7 @@ func TestTUI041_BuiltinCommandsRegistered(t *testing.T) {
 func TestTUI364_RegistryCompleteness(t *testing.T) {
 	// These are the exact built-in slash commands the TUI exposes.
 	knownCommands := []string{
+		"plan",
 		"add-dir", "attach", "cancel", "clear", "compact", "config", "context", "cost", "dashboard", "doctor", "export", "feedback", "fork", "help", "history", "hooks", "init", "keys",
 		"model", "new", "permissions", "plugins", "profiles", "quit", "replay", "resume", "runs", "search",
 		"sessions", "stats", "subagents", "tasks", "rewind", "theme", "title", "undo", "workflow",

cmd/harnesscli/tui/components/messagebubble/assistant.go

@@ -1,6 +1,7 @@
 package messagebubble
 
 import (
+	"github.com/charmbracelet/lipgloss"
 	"strings"
 
 	"go-agent-harness/cmd/harnesscli/tui/components/streamrenderer"
@@ -70,12 +71,19 @@ func (b AssistantBubble) View() string {
 
 	if b.Content != "" {
 		if looksLikeMarkdown(b.Content) {
-			// Render via glamour; strip trailing newlines so we control spacing.
-			rendered := RenderMarkdown(b.Content, width)
+			// Render via glamour at the width left after the indent, and strip
+			// trailing newlines so we control spacing. Glamour pads every line
+			// to its wrap width; rendering at the full width and then indenting
+			// pushed rows past the terminal edge, where the terminal wrapped
+			// them and the renderer's row bookkeeping cut and merged lines
+			// (#1407). Tabs are expanded for the same reason: a terminal skips
+			// cells over a tab without clearing them.
+			rendered := RenderMarkdown(b.Content, contentWidth)
 			rendered = strings.TrimRight(rendered, "\n")
 			// Split rendered output into lines for prefix/indent handling.
 			mdLines := strings.Split(rendered, "\n")
 			for i, line := range mdLines {
+				line = fitLine(line, contentWidth)
 				if b.Title == "" && i == 0 {
 					sb.WriteString(dotRendered)
 					sb.WriteString(" ")
@@ -115,3 +123,18 @@ func (b AssistantBubble) View() string {
 
 	return sb.String()
 }
+
+// fitLine expands tabs, drops trailing padding, and guarantees the line is at
+// most width columns wide so the terminal never has to wrap it (#1407).
+func fitLine(line string, width int) string {
+	line = strings.ReplaceAll(line, "\t", "    ")
+	line = strings.TrimRight(line, " ")
+	if width > 0 && lipgloss.Width(line) > width {
+		runes := []rune(line)
+		for len(runes) > 0 && lipgloss.Width(string(runes)) > width {
+			runes = runes[:len(runes)-1]
+		}
+		line = string(runes)
+	}
+	return line
+}

cmd/harnesscli/tui/components/messagebubble/width_1407_test.go

@@ -0,0 +1,35 @@
+package messagebubble_test
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/charmbracelet/lipgloss"
+
+	"go-agent-harness/cmd/harnesscli/tui/components/messagebubble"
+)
+
+// Issue #1407: a rendered assistant bubble must never be wider than the
+// terminal and must not contain tab characters. Glamour pads lines to its
+// wrap width, and the bubble then adds a 4-column indent; the overflowing
+// rows wrapped in the terminal and the renderer's bookkeeping cut and merged
+// lines ("• Created  calc.go  w", "ok  PASS: calcAdd/0.123s").
+func TestAssistantBubble_FitsWidthAndHasNoTabs(t *testing.T) {
+	md := "Done. Summary:\n\n- Created `calc.go` with an `Add` function that returns the sum of two integers.\n- Created `calc_test.go` with table-driven tests covering positive, negative, mixed signs, and zeros.\n\n```\nPASS\nok  \tcalc\t0.123s\n```\n"
+	for _, width := range []int{120, 80, 60} {
+		out := messagebubble.AssistantBubble{Content: md, Width: width}.View()
+		for i, line := range strings.Split(out, "\n") {
+			if strings.Contains(line, "\t") {
+				t.Errorf("width %d line %d contains a tab: %q", width, i, line)
+			}
+			if w := lipgloss.Width(line); w > width {
+				t.Errorf("width %d line %d is %d columns wide: %q", width, i, w, line)
+			}
+		}
+		// Narrow widths wrap mid-phrase; compare with whitespace collapsed.
+		flat := strings.Join(strings.Fields(out), " ")
+		if !strings.Contains(flat, "sum of two integers") || !strings.Contains(flat, "mixed signs, and zeros") {
+			t.Errorf("width %d: content lost:\n%s", width, out)
+		}
+	}
+}

cmd/harnesscli/tui/config.go

@@ -26,6 +26,8 @@ type TUIConfig struct {
 	// startup so the run history is loaded and new prompts continue the
 	// existing conversation instead of starting a new one.
 	ResumeConversationID string
+	// PlanMode starts the TUI in enforced plan mode (harnesscli --tui --plan-mode).
+	PlanMode bool
 	// SpinnerSeed seeds the thinking-spinner's verb selection. Zero (the default)
 	// uses a time-based seed for whimsical variety in real use; tests set a fixed
 	// non-zero seed so rendered snapshots are deterministic.

cmd/harnesscli/tui/filecomplete.go

@@ -53,7 +53,9 @@ func FilePathCompleter(input string) []string {
 			break
 		}
 	}
-	if !isPathLike {
+	// A bare name such as "@cal" is a path relative to the working directory:
+	// that is what a first-time user types (#1407).
+	if !isPathLike && strings.ContainsAny(partial, " \t") {
 		return nil
 	}
 

cmd/harnesscli/tui/filecomplete_bare_1407_test.go

@@ -0,0 +1,33 @@
+package tui_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"go-agent-harness/cmd/harnesscli/tui"
+)
+
+// Issue #1407: "@cal" + Tab must complete bare relative names, not only
+// paths that start with ./, / or ~. A first-time user types the file name.
+func TestFilePathCompleter_BareRelativeName(t *testing.T) {
+	dir := t.TempDir()
+	for _, f := range []string{"calc.go", "calc_test.go", "go.mod"} {
+		if err := os.WriteFile(filepath.Join(dir, f), []byte("x"), 0o644); err != nil {
+			t.Fatal(err)
+		}
+	}
+	t.Chdir(dir)
+	got := tui.FilePathCompleter("Explain what @cal")
+	if len(got) != 2 {
+		t.Fatalf("want the two calc files, got %v", got)
+	}
+	for _, c := range got {
+		if c != "Explain what @calc.go" && c != "Explain what @calc_test.go" {
+			t.Errorf("unexpected completion %q", c)
+		}
+	}
+	if got := tui.FilePathCompleter("say @go.m"); len(got) != 1 || got[0] != "say @go.mod" {
+		t.Errorf("single bare match must complete fully, got %v", got)
+	}
+}

cmd/harnesscli/tui/model.go

@@ -588,6 +588,7 @@ func New(cfg TUIConfig) Model {
 	m = m.WithAutocompleteProvider(buildCombinedProvider(m.commandRegistry))
 	// Wire slash-complete dropdown.
 	m.slashComplete = buildSlashComplete(m.commandRegistry, m.skillRegistry)
+	m.planMode = cfg.PlanMode
 	if cfg.ResumeConversationID != "" {
 		m.conversationID = cfg.ResumeConversationID
 	}
@@ -799,6 +800,9 @@ func (m Model) ConversationID() string {
 }
 
 // SelectedModel returns the currently active model ID (for testing).
+// StatusBarModelLabel exposes the status bar's model segment (for testing).
+func (m Model) StatusBarModelLabel() string { return m.statusBarModelLabel() }
+
 // EffectiveModelAndProvider exposes the model id and provider the next run
 // will be sent with (for testing).
 func (m Model) EffectiveModelAndProvider() (string, string) { return m.effectiveModelAndProvider() }
@@ -1971,6 +1975,21 @@ func (m *Model) resetTranscriptView() {
 	m.clearCompactionBlocks()
 }
 
+// executePlanCommand toggles enforced plan mode explicitly. ctrl+o only
+// reaches plan mode when no tool call has ever run in the session, so a
+// first-time user needs a discoverable command (#1407).
+func executePlanCommand(m *Model, _ Command) ([]tea.Cmd, bool) {
+	if m.runActive {
+		return []tea.Cmd{m.setStatusMsg("Plan mode can't change while a run is active — wait for it to finish or press Esc to cancel")}, false
+	}
+	m.planMode = !m.planMode
+	m.statusBar.SetModel(m.statusBarModelLabel())
+	if m.planMode {
+		return []tea.Cmd{m.setStatusMsg("Plan mode: ON — the agent only edits .harness/plan.md until you approve its plan (/plan to turn off)")}, false
+	}
+	return []tea.Cmd{m.setStatusMsg("Plan mode: OFF")}, false
+}
+
 func executeClearCommand(m *Model, _ Command) ([]tea.Cmd, bool) {
 	m.resetTranscriptView()
 	return []tea.Cmd{m.setStatusMsg("Conversation cleared")}, false
@@ -3150,8 +3169,9 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			} else if !m.runActive {
 				// Idle (no run active, no active tool): toggle plan mode.
 				m.planMode = !m.planMode
+				m.statusBar.SetModel(m.statusBarModelLabel())
 				if m.planMode {
-					cmds = append(cmds, m.setStatusMsg("Plan mode: ON"))
+					cmds = append(cmds, m.setStatusMsg("Plan mode: ON — the agent only edits .harness/plan.md until you approve its plan (/plan to turn off)"))
 				} else {
 					cmds = append(cmds, m.setStatusMsg("Plan mode: OFF"))
 				}
@@ -5858,6 +5878,14 @@ func (m Model) effectiveModelAndProvider() (model, provider string) {
 // including reasoning effort suffix and gateway indicator if applicable.
 func (m Model) statusBarModelLabel() string {
 	label := displayModelName(m.selectedModel)
+	if m.planMode {
+		// Make the mode visible; ctrl+o is overloaded and /plan toggles it (#1407).
+		if label == "" {
+			label = "PLAN"
+		} else {
+			label = "PLAN · " + label
+		}
+	}
 	if m.selectedReasoningEffort != "" {
 		label += " (" + m.selectedReasoningEffort + ")"
 	}

cmd/harnesscli/tui/plan_command_1407_test.go

@@ -0,0 +1,50 @@
+package tui_test
+
+import (
+	"strings"
+	"testing"
+
+	"go-agent-harness/cmd/harnesscli/tui"
+)
+
+// Issue #1407: plan mode must be reachable and visible. ctrl+o is overloaded
+// (it expands tool calls whenever any tool has run), so a /plan command
+// toggles it explicitly and the status bar shows the mode.
+func TestPlanCommand_TogglesAndShowsInStatusBar(t *testing.T) {
+	m := initModel(t, 120, 40)
+	if m.PlanMode() {
+		t.Fatal("plan mode must start off")
+	}
+	m = sendSlashCommand(m, "/plan")
+	if !m.PlanMode() {
+		t.Fatal("/plan must turn plan mode on")
+	}
+	if !strings.Contains(m.StatusBarModelLabel(), "PLAN") {
+		t.Fatalf("status bar must show the PLAN badge while plan mode is on, got %q", m.StatusBarModelLabel())
+	}
+	if !strings.Contains(m.StatusMsg(), "Plan mode") {
+		t.Fatalf("status must confirm the toggle, got %q", m.StatusMsg())
+	}
+	m = sendSlashCommand(m, "/plan")
+	if m.PlanMode() || strings.Contains(m.StatusBarModelLabel(), "PLAN") {
+		t.Fatal("/plan again must turn plan mode off and drop the badge")
+	}
+}
+
+func TestPlanCommand_InSlashMenu(t *testing.T) {
+	m := initModel(t, 120, 40)
+	m = typeIntoModel(m, "/pla")
+	if !strings.Contains(m.View(), "/plan ") && !strings.Contains(m.View(), "/plan\t") && !strings.Contains(m.View(), "/plan  ") {
+		t.Fatalf("/plan must appear in the slash menu:\n%s", m.View())
+	}
+}
+
+// harnesscli --tui --plan-mode must start the TUI in plan mode.
+func TestTUIConfig_PlanModeFlag(t *testing.T) {
+	cfg := tui.DefaultTUIConfig()
+	cfg.PlanMode = true
+	m := tui.New(cfg)
+	if !m.PlanMode() {
+		t.Fatal("TUIConfig.PlanMode must start the TUI in plan mode")
+	}
+}