fix(tui): render the ? help as an overlay, not a full-screen replace

Pressing ? replaced the entire TUI with the shortcut block: View() short-
circuited to renderKeybindingHelpOverlay, which centers the block on a blank
canvas, so the transcript, title bar, and composer all vanished. Every other
popup (model picker, suggestions, wizards) composites over the chat instead.

Route the help overlay through the SAME viewport-overlay path the pickers use:
add keybindingHelpOverlay(width) (returns "" when closed, else the centered
block) as the highest-priority case in transcriptView's overlay switch and in
twoColumnTranscriptView, and drop the content-replacement branch in View(). The
overlay now draws on top of the chat via the existing overlayViewportLines
compositing, keeping the transcript/title bar/composer visible behind it. Input
handling is unchanged — the modal key-swallow + ?/Esc/q/Enter dismiss run before
render — so only the presentation changes.

Tests: the help overlay composites over the chat chrome (title bar + composer
survive) and over a populated transcript row (red-green: with the old
full-replace both the chrome and the body are gone); existing
open/close/swallow/content tests unchanged.

Fixes #419

README.md

@@ -51,6 +51,27 @@ The npm package installs a small wrapper plus the matching Zero binary for your
 platform from GitHub Releases. It supports Linux, macOS, and Windows on x64 and
 arm64.
 
+### Bun
+
+Bun does not run dependency lifecycle scripts by default, so the `postinstall`
+that fetches the Zero binary is skipped and the first run fails with
+`No native binary found next to the npm wrapper`.
+
+Install with Bun, then fetch the binary in one of two ways:
+
+```bash
+# Option A: run the installer manually
+bun add @gitlawb/zero
+node node_modules/@gitlawb/zero/scripts/postinstall.mjs
+
+# Option B: allow the postinstall to run on install
+# add to your package.json:  "trustedDependencies": ["@gitlawb/zero"]
+bun add @gitlawb/zero
+```
+
+For global installs (`bun add -g @gitlawb/zero`), use Option A against the
+global install path, or prefer the install scripts below.
+
 ### Install scripts
 
 Linux/macOS:

bin/zero.js

@@ -54,8 +54,26 @@ const nativePath = join(packageRoot, zeroBinaryName());
 const localControlHelpers = localControlHelperManifest(packageRoot);
 
 if (!existsSync(nativePath)) {
+  const postinstallScript = join(packageRoot, 'scripts', 'postinstall.mjs');
+  const ranByBun = process.execPath.includes('bun') || !!process.versions?.bun;
   console.error(
-    '[zero] No native binary found next to the npm wrapper. Reinstall the zero package or run `go run ./cmd/zero-release build` from the repository.'
+    '[zero] No native binary found next to the npm wrapper.\n' +
+      'The platform binary is fetched at install time by a postinstall script,\n' +
+      'which did not run (or was skipped) for this install.\n' +
+      '\n' +
+      'Fix it now by running the installer manually:\n' +
+      `  node "${postinstallScript}"\n` +
+      '\n' +
+      (ranByBun
+        ? 'You installed with Bun, which does not run dependency lifecycle scripts\n' +
+          'by default. To let it run on future installs, add zero to your\n' +
+          'project\'s trustedDependencies:\n' +
+          '  "trustedDependencies": ["@gitlawb/zero"]\n' +
+          'then reinstall.\n' +
+          '\n'
+        : '') +
+      'If that fails, build from source: https://github.com/Gitlawb/zero\n' +
+      '(go run ./cmd/zero, requires Go 1.25+).',
   );
   process.exit(1);
 }

docs/INSTALL.md

@@ -24,6 +24,38 @@ Requirements:
 - Node.js 18+
 - network access to npm and GitHub Releases
 
+## Bun
+
+Bun is "default-secure" and does not run lifecycle scripts of installed
+dependencies (only the installing project's own scripts), so the `postinstall`
+that fetches the Zero binary is silently skipped. The first run then fails with
+`No native binary found next to the npm wrapper`.
+
+To install with Bun, either run the installer manually after installing:
+
+```bash
+bun add @gitlawb/zero
+node node_modules/@gitlawb/zero/scripts/postinstall.mjs
+```
+
+Or allow the postinstall to run by adding the package to your project's
+`trustedDependencies` before installing:
+
+```json
+{
+  "trustedDependencies": ["@gitlawb/zero"]
+}
+```
+
+```bash
+bun add @gitlawb/zero
+```
+
+For global installs (`bun add -g @gitlawb/zero`), run the installer manually
+against the global install path, or use the install scripts below.
+
+Reference: <https://bun.sh/docs/pm/lifecycle>
+
 ## Linux And macOS Script
 
 Install the latest release:

internal/agent/loop.go

@@ -2159,6 +2159,18 @@ func buildPermissionEvent(call ToolCall, tool tools.Tool, args map[string]any, p
 		}
 	}
 
+	// A command that explicitly requests additional sandbox permissions
+	// (sandbox_permissions: with_additional_permissions) is an ELEVATION the user
+	// must consent to, even when the base command's sandbox decision was Allow.
+	// shouldRequestPermission blocks on OnPermissionRequest for exactly this case,
+	// so the event MUST be a prompt — otherwise it carried Action=allow while the
+	// loop waited on a decision, and a UI that renders only prompts (the TUI)
+	// dropped it, deadlocking the run. Keep this consistent with
+	// shouldRequestPermission's own condition.
+	if action == PermissionActionAllow && !permissionGranted && shellCommandAdditionalPermissionsRequested(args) {
+		action = PermissionActionPrompt
+	}
+
 	if safety.Permission == tools.PermissionAllow && action == PermissionActionAllow && !grantMatched && block == nil {
 		return PermissionEvent{}, false
 	}

internal/agent/permission_additional_perms_test.go

@@ -0,0 +1,70 @@
+package agent
+
+import (
+	"context"
+	"testing"
+
+	"github.com/Gitlawb/zero/internal/sandbox"
+	"github.com/Gitlawb/zero/internal/tools"
+)
+
+// promptShellTool is a minimal shell-style tool whose Safety requires a prompt,
+// standing in for bash so buildPermissionEvent can be exercised directly.
+type promptShellTool struct{}
+
+func (promptShellTool) Name() string        { return "bash" }
+func (promptShellTool) Description() string { return "run a shell command" }
+func (promptShellTool) Parameters() tools.Schema {
+	return tools.Schema{Type: "object", AdditionalProperties: false}
+}
+func (promptShellTool) Safety() tools.Safety {
+	return tools.Safety{SideEffect: tools.SideEffectShell, Permission: tools.PermissionPrompt, Reason: "runs a shell command"}
+}
+func (promptShellTool) Run(context.Context, map[string]any) tools.Result {
+	return tools.Result{Status: tools.StatusOK}
+}
+
+// A command whose sandbox decision is Allow but that explicitly requests
+// additional sandbox permissions is an ELEVATION: it must be surfaced as a
+// prompt, never Action=allow. Previously it carried allow while the loop still
+// blocked on OnPermissionRequest, and the TUI (which renders only prompts)
+// dropped it → the run deadlocked forever. This is the exact gpt-5.5
+// folder-creation shape captured in the reported hang.
+func TestBuildPermissionEventPromptsForAdditionalPermissions(t *testing.T) {
+	call := ToolCall{ID: "call_1", Name: "bash", Arguments: `{}`}
+	args := map[string]any{
+		"command":             "mkdir foo && cd foo && go mod init foo",
+		"sandbox_permissions": string(tools.SandboxPermissionsWithAdditionalPermissions),
+	}
+	// Base command allowed by the sandbox…
+	decision := &sandbox.Decision{Action: sandbox.ActionAllow}
+
+	event, ok := buildPermissionEvent(call, promptShellTool{}, args, false, PermissionModeAsk, Options{}, decision)
+	if !ok {
+		t.Fatal("buildPermissionEvent returned ok=false; the elevation request must produce an event")
+	}
+	if event.Action != PermissionActionPrompt {
+		t.Fatalf("Action = %q, want prompt — an additional-permissions elevation must ask the user, not auto-allow", event.Action)
+	}
+	// Sanity: shouldRequestPermission agrees the loop blocks on this.
+	if !shouldRequestPermission(promptShellTool{}, args, false, decision) {
+		t.Fatal("shouldRequestPermission must be true for an additional-permissions request")
+	}
+}
+
+// Without the additional-permissions flag, a sandbox-allowed command is NOT a
+// prompt (shouldRequestPermission is false; it just runs) — the override must
+// not over-reach and prompt for ordinary allowed commands.
+func TestBuildPermissionEventKeepsAllowForOrdinaryAllowedCommand(t *testing.T) {
+	call := ToolCall{ID: "call_2", Name: "bash", Arguments: `{}`}
+	args := map[string]any{"command": "ls"}
+	decision := &sandbox.Decision{Action: sandbox.ActionAllow}
+
+	event, _ := buildPermissionEvent(call, promptShellTool{}, args, false, PermissionModeAsk, Options{}, decision)
+	if event.Action == PermissionActionPrompt {
+		t.Fatalf("Action = prompt for an ordinary allowed command; want allow (no spurious prompt)")
+	}
+	if shouldRequestPermission(promptShellTool{}, args, false, decision) {
+		t.Fatal("shouldRequestPermission must be false for an ordinary sandbox-allowed command")
+	}
+}

internal/mcp/client_test.go

@@ -11,6 +11,7 @@ import (
 	"os"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"testing"
 	"time"
 
@@ -211,6 +212,85 @@ func TestHTTPClientListsAndCallsTools(t *testing.T) {
 	}
 }
 
+func TestHTTPClientFollowsSameOriginRedirect(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	testServer := httptest.NewServer(http.HandlerFunc(func(response http.ResponseWriter, request *http.Request) {
+		if request.URL.Path == "/mcp" {
+			http.Redirect(response, request, "/redirected", http.StatusTemporaryRedirect)
+			return
+		}
+		if request.Method != http.MethodPost || request.URL.Path != "/redirected" {
+			t.Errorf("request = %s %s, want POST /redirected", request.Method, request.URL.Path)
+			http.Error(response, "bad request", http.StatusNotFound)
+			return
+		}
+		if got := request.Header.Get("X-Api-Key"); got != "secret" {
+			t.Errorf("X-Api-Key = %q, want secret", got)
+			http.Error(response, "missing auth", http.StatusUnauthorized)
+			return
+		}
+
+		message := readHTTPRPCMessage(t, request)
+		switch message.Method {
+		case "initialize":
+			writeHTTPRPCResponse(t, response, message.ID, map[string]any{"protocolVersion": "2024-11-05"})
+		case "notifications/initialized":
+			response.WriteHeader(http.StatusAccepted)
+		default:
+			writeHTTPRPCResponse(t, response, message.ID, map[string]any{})
+		}
+	}))
+	defer testServer.Close()
+
+	client, err := Connect(ctx, Server{
+		Name:    "docs",
+		Type:    ServerTypeHTTP,
+		URL:     testServer.URL + "/mcp",
+		Headers: map[string]string{"X-Api-Key": "secret"},
+	})
+	if err != nil {
+		t.Fatalf("Connect() error = %v", err)
+	}
+	if err := client.Close(); err != nil {
+		t.Fatalf("Close() error = %v", err)
+	}
+}
+
+func TestHTTPClientRejectsCrossOriginRedirectBeforeSendingHeaders(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	var targetHits int32
+	target := httptest.NewServer(http.HandlerFunc(func(response http.ResponseWriter, request *http.Request) {
+		atomic.AddInt32(&targetHits, 1)
+		if got := request.Header.Get("X-Api-Key"); got != "" {
+			t.Errorf("redirect target received X-Api-Key = %q", got)
+		}
+		response.WriteHeader(http.StatusOK)
+	}))
+	defer target.Close()
+
+	redirector := httptest.NewServer(http.HandlerFunc(func(response http.ResponseWriter, request *http.Request) {
+		http.Redirect(response, request, target.URL+"/mcp", http.StatusTemporaryRedirect)
+	}))
+	defer redirector.Close()
+
+	_, err := Connect(ctx, Server{
+		Name:    "docs",
+		Type:    ServerTypeHTTP,
+		URL:     redirector.URL + "/mcp",
+		Headers: map[string]string{"X-Api-Key": "secret"},
+	})
+	if err == nil || !strings.Contains(err.Error(), "cross-origin redirect") {
+		t.Fatalf("Connect() error = %v, want cross-origin redirect error", err)
+	}
+	if got := atomic.LoadInt32(&targetHits); got != 0 {
+		t.Fatalf("redirect target hits = %d, want 0", got)
+	}
+}
+
 func TestSSEClientListsAndCallsToolsFromRemoteStream(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()
@@ -340,6 +420,53 @@ func TestSSEClientListsAndCallsToolsFromRemoteStream(t *testing.T) {
 	}
 }
 
+func TestSSEClientRejectsCrossOriginEndpointBeforeSendingHeaders(t *testing.T) {
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	var targetHits int32
+	target := httptest.NewServer(http.HandlerFunc(func(response http.ResponseWriter, request *http.Request) {
+		atomic.AddInt32(&targetHits, 1)
+		if got := request.Header.Get("X-Api-Key"); got != "" {
+			t.Errorf("SSE endpoint target received X-Api-Key = %q", got)
+		}
+		response.WriteHeader(http.StatusAccepted)
+	}))
+	defer target.Close()
+
+	stream := httptest.NewServer(http.HandlerFunc(func(response http.ResponseWriter, request *http.Request) {
+		if got := request.Header.Get("X-Api-Key"); got != "secret" {
+			t.Errorf("X-Api-Key = %q, want secret on configured SSE server", got)
+			http.Error(response, "missing auth", http.StatusUnauthorized)
+			return
+		}
+		if request.Method != http.MethodGet || request.URL.Path != "/sse" {
+			t.Errorf("request = %s %s, want GET /sse", request.Method, request.URL.Path)
+			http.Error(response, "bad request", http.StatusNotFound)
+			return
+		}
+		response.Header().Set("Content-Type", "text/event-stream")
+		_, _ = fmt.Fprintf(response, "event: endpoint\ndata: %s/messages\n\n", target.URL)
+		if flusher, ok := response.(http.Flusher); ok {
+			flusher.Flush()
+		}
+	}))
+	defer stream.Close()
+
+	_, err := Connect(ctx, Server{
+		Name:    "docs",
+		Type:    ServerTypeSSE,
+		URL:     stream.URL + "/sse",
+		Headers: map[string]string{"X-Api-Key": "secret"},
+	})
+	if err == nil || !strings.Contains(err.Error(), "endpoint origin") {
+		t.Fatalf("Connect() error = %v, want cross-origin endpoint error", err)
+	}
+	if got := atomic.LoadInt32(&targetHits); got != 0 {
+		t.Fatalf("SSE endpoint target hits = %d, want 0", got)
+	}
+}
+
 func TestHTTPClientReportsNonOKStatus(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 	defer cancel()

internal/mcp/network_client.go

@@ -733,7 +733,11 @@ func resolveSSEEndpointURL(baseValue string, endpointValue string) (string, erro
 	if err != nil {
 		return "", fmt.Errorf("parse MCP SSE endpoint URL: %w", err)
 	}
-	return baseURL.ResolveReference(endpointURL).String(), nil
+	resolvedURL := baseURL.ResolveReference(endpointURL)
+	if !sameMCPOrigin(baseURL, resolvedURL) {
+		return "", fmt.Errorf("MCP SSE endpoint origin %s differs from configured server origin %s", mcpOrigin(resolvedURL), mcpOrigin(baseURL))
+	}
+	return resolvedURL.String(), nil
 }
 
 func rpcResponseKey(id any) string {
@@ -873,10 +877,10 @@ func (source *storeTokenSource) Refresh(ctx context.Context) (string, error) {
 
 // oauthHTTPClient returns an HTTP client whose transport attaches OAuth bearer
 // tokens and refreshes them on 401 for OAuth-configured servers. Servers that do
-// not declare OAuth get the default client unchanged.
+// not declare OAuth use the default transport with the same MCP redirect guard.
 func oauthHTTPClient(server Server) (*http.Client, error) {
 	if !strings.EqualFold(strings.TrimSpace(server.Auth), ServerAuthOAuth) {
-		return http.DefaultClient, nil
+		return mcpHTTPClient(server, nil), nil
 	}
 	store, err := NewTokenStore(TokenStoreOptions{})
 	if err != nil {
@@ -888,5 +892,5 @@ func oauthHTTPClient(server Server) (*http.Client, error) {
 		httpClient: http.DefaultClient,
 		now:        time.Now,
 	}
-	return &http.Client{Transport: newOAuthRoundTripper(http.DefaultTransport, source, server.Name)}, nil
+	return mcpHTTPClient(server, newOAuthRoundTripper(http.DefaultTransport, source, server.Name)), nil
 }

internal/mcp/network_client_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"strings"
 	"sync/atomic"
 	"testing"
@@ -149,6 +150,141 @@ func TestOAuthRoundTripperDoesNotRetryAfterSuccessfulNon401(t *testing.T) {
 	}
 }
 
+func TestOAuthRoundTripperRejectsCrossOriginRedirectBeforeBearerLeak(t *testing.T) {
+	source := &fakeTokenSource{}
+	source.access.Store("access-secret")
+	source.refreshFunc = func() (string, error) { return "access-fresh", nil }
+
+	var targetHits int32
+	target := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		atomic.AddInt32(&targetHits, 1)
+		if got := r.Header.Get("Authorization"); got != "" {
+			t.Errorf("redirect target received Authorization = %q", got)
+		}
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer target.Close()
+
+	redirector := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Redirect(w, r, target.URL+"/mcp", http.StatusTemporaryRedirect)
+	}))
+	defer redirector.Close()
+
+	client := mcpHTTPClient(
+		Server{Name: "oauth-docs", Type: ServerTypeHTTP},
+		newOAuthRoundTripper(http.DefaultTransport, source, "oauth-docs"),
+	)
+	resp, err := client.Get(redirector.URL + "/mcp")
+	if resp != nil {
+		_ = resp.Body.Close()
+	}
+	if err == nil || !strings.Contains(err.Error(), "cross-origin redirect") {
+		t.Fatalf("Get() error = %v, want cross-origin redirect error", err)
+	}
+	if got := atomic.LoadInt32(&targetHits); got != 0 {
+		t.Fatalf("redirect target hits = %d, want 0", got)
+	}
+}
+
+func TestSameMCPOriginNormalizesDefaultPorts(t *testing.T) {
+	for _, tc := range []struct {
+		name  string
+		left  string
+		right string
+		want  bool
+	}{
+		{
+			name:  "https default port",
+			left:  "https://example.test/mcp",
+			right: "https://EXAMPLE.test:443/other",
+			want:  true,
+		},
+		{
+			name:  "http default port",
+			left:  "http://example.test/mcp",
+			right: "http://example.test:80/other",
+			want:  true,
+		},
+		{
+			name:  "different scheme",
+			left:  "https://example.test/mcp",
+			right: "http://example.test:443/other",
+			want:  false,
+		},
+		{
+			name:  "different port",
+			left:  "https://example.test/mcp",
+			right: "https://example.test:8443/other",
+			want:  false,
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			left, err := url.Parse(tc.left)
+			if err != nil {
+				t.Fatal(err)
+			}
+			right, err := url.Parse(tc.right)
+			if err != nil {
+				t.Fatal(err)
+			}
+			if got := sameMCPOrigin(left, right); got != tc.want {
+				t.Fatalf("sameMCPOrigin(%q, %q) = %v, want %v", tc.left, tc.right, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestResolveSSEEndpointURLRestrictsOrigin(t *testing.T) {
+	for _, tc := range []struct {
+		name     string
+		base     string
+		endpoint string
+		want     string
+		wantErr  string
+	}{
+		{
+			name:     "relative endpoint",
+			base:     "https://example.test/sse",
+			endpoint: "/messages",
+			want:     "https://example.test/messages",
+		},
+		{
+			name:     "absolute same origin",
+			base:     "https://example.test/sse",
+			endpoint: "https://example.test/messages",
+			want:     "https://example.test/messages",
+		},
+		{
+			name:     "default port equivalent",
+			base:     "https://example.test/sse",
+			endpoint: "https://example.test:443/messages",
+			want:     "https://example.test:443/messages",
+		},
+		{
+			name:     "cross origin",
+			base:     "https://example.test/sse",
+			endpoint: "https://evil.test/messages",
+			wantErr:  "differs from configured server origin",
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			got, err := resolveSSEEndpointURL(tc.base, tc.endpoint)
+			if tc.wantErr != "" {
+				if err == nil || !strings.Contains(err.Error(), tc.wantErr) {
+					t.Fatalf("resolveSSEEndpointURL() error = %v, want %q", err, tc.wantErr)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("resolveSSEEndpointURL() error = %v", err)
+			}
+			if got != tc.want {
+				t.Fatalf("resolveSSEEndpointURL() = %q, want %q", got, tc.want)
+			}
+		})
+	}
+}
+
 func TestNonOAuthServerIsUnaffected(t *testing.T) {
 	// Regression: a server without auth must not get a bearer header or any
 	// OAuth round tripper, and must connect normally.

internal/mcp/network_redirect.go

@@ -0,0 +1,74 @@
+package mcp
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+const maxMCPRedirects = 10
+
+func mcpHTTPClient(server Server, transport http.RoundTripper) *http.Client {
+	return &http.Client{
+		Transport:     transport,
+		CheckRedirect: checkMCPRedirect(server),
+	}
+}
+
+func checkMCPRedirect(server Server) func(*http.Request, []*http.Request) error {
+	return func(request *http.Request, via []*http.Request) error {
+		if len(via) >= maxMCPRedirects {
+			return fmt.Errorf("MCP %s server %s stopped after %d redirects", server.Type, server.Name, maxMCPRedirects)
+		}
+		if len(via) == 0 {
+			return nil
+		}
+		if !sameMCPOrigin(via[0].URL, request.URL) {
+			return fmt.Errorf("MCP %s server %s refused cross-origin redirect to %s", server.Type, server.Name, mcpOrigin(request.URL))
+		}
+		return nil
+	}
+}
+
+func sameMCPOrigin(left *url.URL, right *url.URL) bool {
+	if left == nil || right == nil {
+		return false
+	}
+	return strings.EqualFold(left.Scheme, right.Scheme) &&
+		strings.EqualFold(left.Hostname(), right.Hostname()) &&
+		effectiveMCPPort(left) == effectiveMCPPort(right)
+}
+
+func effectiveMCPPort(value *url.URL) string {
+	if value == nil {
+		return ""
+	}
+	if port := value.Port(); port != "" {
+		return port
+	}
+	switch strings.ToLower(value.Scheme) {
+	case "http":
+		return "80"
+	case "https":
+		return "443"
+	default:
+		return ""
+	}
+}
+
+func mcpOrigin(value *url.URL) string {
+	if value == nil {
+		return "<nil>"
+	}
+	host := value.Hostname()
+	port := effectiveMCPPort(value)
+	if port != "" {
+		host = net.JoinHostPort(host, port)
+	}
+	if value.Scheme == "" {
+		return host
+	}
+	return strings.ToLower(value.Scheme) + "://" + host
+}

internal/tui/keybinding_help.go

@@ -133,6 +133,18 @@ func (m model) renderKeybindingHelpOverlay(width int, height int) string {
 	return centerRenderedBlock(block, width)
 }
 
+// keybindingHelpOverlay returns the `?` shortcut overlay as a centered block to
+// COMPOSITE over the transcript — the same viewport-overlay path the model
+// picker and suggestions use — or "" when it is not open. Rendering it this way
+// (rather than replacing the whole View) keeps the chat visible behind it, so
+// `?` behaves like every other popup instead of blanking the screen (#419).
+func (m model) keybindingHelpOverlay(width int) string {
+	if !m.helpOverlay {
+		return ""
+	}
+	return m.renderKeybindingHelpOverlay(width, m.height)
+}
+
 // keybindingHelpOverlayWidth picks the overlay width: wide enough that the
 // descriptions don't truncate next to the key column, capped, and never wider
 // than the terminal.

internal/tui/keybinding_help_test.go

@@ -105,3 +105,56 @@ func TestKeybindingGroupsAreWellFormed(t *testing.T) {
 		}
 	}
 }
+
+// #419: the `?` help overlay must render ON TOP of the chat (like the model
+// picker), not REPLACE the whole screen. The old full-screen replace produced
+// only the centered shortcut block on a blank canvas — no title bar, no
+// composer. So with the overlay open, the surrounding chat chrome that is NOT
+// covered by the centered box (the model title bar at top, the composer at
+// bottom) must still be present alongside "Keyboard Shortcuts".
+func TestHelpOverlayCompositesOverChatNotReplacingIt(t *testing.T) {
+	m := newModel(context.Background(), Options{ModelName: "gpt-4o"})
+	m.width = 100
+	m.height = 40
+	m.altScreen = true
+
+	base := plainRender(t, m.View()) // no overlay: baseline chrome
+	m.helpOverlay = true
+	over := plainRender(t, m.View())
+
+	if !strings.Contains(over, "Keyboard Shortcuts") {
+		t.Fatalf("help overlay not rendered:\n%s", over)
+	}
+	// Chrome that renders in the baseline (and sits outside the centered overlay
+	// box) must survive behind the overlay. The full-screen replace showed none
+	// of it.
+	for _, marker := range []string{"gpt-4o", "describe a task"} {
+		if !strings.Contains(base, marker) {
+			t.Fatalf("precondition: baseline chat should contain %q:\n%s", marker, base)
+		}
+		if !strings.Contains(over, marker) {
+			t.Fatalf("#419: help replaced the chat instead of overlaying it; %q is gone:\n%s", marker, over)
+		}
+	}
+}
+
+// A populated transcript row also survives behind the overlay (peeking out to
+// the left of the centered box), proving the chat body — not just the chrome —
+// is composited under the overlay rather than discarded.
+func TestHelpOverlayKeepsTranscriptBodyBehindIt(t *testing.T) {
+	m := newModel(context.Background(), Options{ModelName: "gpt-4o"})
+	m.width = 120
+	m.height = 40
+	m.altScreen = true
+	m.transcript = appendTranscriptRow(m.transcript, transcriptRow{kind: rowUser, text: "hello there this is a chat line"})
+	m.helpOverlay = true
+
+	view := plainRender(t, m.View())
+	if !strings.Contains(view, "Keyboard Shortcuts") {
+		t.Fatalf("help overlay not rendered:\n%s", view)
+	}
+	// The start of the transcript line peeks to the left of the centered box.
+	if !strings.Contains(view, "hello") {
+		t.Fatalf("#419: transcript body was replaced by the help overlay:\n%s", view)
+	}
+}

internal/tui/model.go

@@ -1068,7 +1068,7 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m = m.disarmCancelConfirmation()
 		}
 		// The `?` help overlay is modal: `?`, Esc, q, or Enter close it; every
-		// other key is swallowed so nothing types into the hidden composer.
+		// other key is swallowed so nothing types into the composer behind it.
 		if m.helpOverlay {
 			if keyText(msg) == "?" || keyText(msg) == "q" || keyIs(msg, tea.KeyEsc) || keyIs(msg, tea.KeyEnter) || keyCtrl(msg, 'c') {
 				m.helpOverlay = false
@@ -1669,17 +1669,38 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 		// when the loop is already running or there is nothing to animate.
 		return m, m.ensureSpinnerTick()
 	case permissionRequestMsg:
+		// The agent goroutine that raised this request is BLOCKED waiting on the
+		// decision callback, so every branch below must resolve it exactly once —
+		// or store it in pendingPermission, which resolves it on the user's reply.
+		// Dropping a request without resolving parks the run forever (the reported
+		// "stuck for 33 minutes" deadlock): the agent waits on a decision channel
+		// nothing will ever signal, with no visible prompt and no network activity.
 		if msg.runID != m.activeRunID {
+			// A superseded/stale run: unblock its parked goroutine now rather than
+			// relying on that run's context cancel to fire first.
+			if msg.decide != nil {
+				msg.decide(agent.PermissionDecision{Action: agent.PermissionDecisionCancel, Reason: "run superseded"})
+			}
+			return m, nil
+		}
+		if msg.request.Action != agent.PermissionActionPrompt {
+			// Not a user-facing prompt (e.g. a sandbox-allowed command that still
+			// blocked because it requested additional permissions). The UI has
+			// nothing to ask, so resolve immediately and FAIL CLOSED — never
+			// silently grant access that was never surfaced to the user. (The agent
+			// now marks such elevation requests as prompts, so in practice this is a
+			// defensive backstop; matches the ACP handler's fail-closed contract.)
+			if msg.decide != nil {
+				msg.decide(autoResolvedPermissionDecision(msg.request.Action))
+			}
 			return m, nil
 		}
 		promptRow := permissionTranscriptRow(permissionEventFromRequest(msg.request))
 		promptRow.runID = msg.runID
 		m.transcript = appendTranscriptRow(m.transcript, promptRow)
-		if msg.request.Action == agent.PermissionActionPrompt {
-			m.pendingPermission = &pendingPermissionPrompt{
-				request: msg.request,
-				decide:  msg.decide,
-			}
+		m.pendingPermission = &pendingPermissionPrompt{
+			request: msg.request,
+			decide:  msg.decide,
 		}
 		return m, nil
 	case askUserRequestMsg:
@@ -2097,8 +2118,6 @@ func (m model) View() tea.View {
 	var content string
 	if m.setup.visible {
 		content = m.setupView(chatWidth(m.width))
-	} else if m.helpOverlay {
-		content = m.renderKeybindingHelpOverlay(chatWidth(m.width), m.height)
 	} else if m.transcriptDetailed {
 		content = m.detailedTranscriptView()
 	} else {
@@ -2173,6 +2192,7 @@ func (m model) transcriptView() string {
 		return body + footer
 	}
 
+	helpOverlay := m.keybindingHelpOverlay(width)
 	suggestionOverlay := m.suggestionOverlay(width)
 	providerOverlay := m.providerWizardOverlay(width)
 	mcpAddOverlay := m.mcpAddWizardOverlay(width)
@@ -2180,6 +2200,8 @@ func (m model) transcriptView() string {
 	pickerOverlay := m.pickerOverlay(width)
 	viewportOverlay := ""
 	switch {
+	case helpOverlay != "":
+		viewportOverlay = helpOverlay
 	case providerOverlay != "":
 		viewportOverlay = providerOverlay
 	case mcpAddOverlay != "":
@@ -2241,6 +2263,11 @@ func (m model) twoColumnTranscriptView() string {
 	if m.transcriptEmpty() && !m.pending {
 		overlayForViewport = ""
 	}
+	// The `?` help overlay composites over the chat like the pickers — set it
+	// after the empty-transcript clear so a user-toggled overlay always shows.
+	if helpOverlay := m.keybindingHelpOverlay(width); helpOverlay != "" {
+		overlayForViewport = helpOverlay
+	}
 
 	header := m.pinnedTitleBar(width)
 	chatBlock := viewLines(m.scrollableTranscriptItemsView(header, bodyItems, footer, width, overlayForViewport))
@@ -4525,6 +4552,21 @@ func (m model) sendPermissionRequest(runID int, request agent.PermissionRequest,
 	m.runtimeMessageSink(permissionRequestMsg{runID: runID, request: request, decide: decide})
 }
 
+// autoResolvedPermissionDecision resolves a permission request the TUI cannot
+// turn into a user prompt (Action != prompt). The agent is blocked awaiting a
+// decision, so one must ALWAYS be produced. Only an explicit Cancel is honored
+// as such; every other non-prompt action — including allow — is DENIED, so the
+// UI never silently grants access it did not surface for approval.
+func autoResolvedPermissionDecision(action agent.PermissionAction) agent.PermissionDecision {
+	if action == agent.PermissionActionCancel {
+		return agent.PermissionDecision{Action: agent.PermissionDecisionCancel, Reason: "run cancelled"}
+	}
+	return agent.PermissionDecision{
+		Action: agent.PermissionDecisionDeny,
+		Reason: "permission request could not be surfaced for approval",
+	}
+}
+
 func (m model) sendAskUserRequest(runID int, request agent.AskUserRequest, answer func([]string)) {
 	if m.runtimeMessageSink == nil {
 		return

internal/tui/model_picker_display_test.go

@@ -0,0 +1,57 @@
+package tui
+
+import "testing"
+
+// The model picker must title each row with the model NAME, not the models.dev
+// marketing description. Regression: Ollama Cloud models resolved full-sentence
+// descriptions from the remote catalog, so rows showed sentences and several
+// models sharing one description looked like exact duplicates (issue: /model
+// list rendered descriptions as titles).
+func TestModelPickerDisplayNamePrefersModelName(t *testing.T) {
+	sentence := "DeepSeek chat model for instruction following, coding, and analysis"
+	cases := []struct {
+		id          string
+		description string
+		want        string
+	}{
+		{"deepseek-v3.2", sentence, "Deepseek V3.2"},
+		{"deepseek-v3.2-thinking", sentence, "Deepseek V3.2 Thinking"},
+		{"glm-5.2", "GLM flagship model", "GLM 5.2"},
+		{"qwen3-coder:480b", "Qwen coding agent model for repository tasks", "Qwen3 Coder 480b"},
+		{"anthropic/claude-sonnet-4.6", "some blurb", "Claude Sonnet 4.6"},
+	}
+	for _, tc := range cases {
+		if got := modelPickerDisplayName(tc.id, tc.description); got != tc.want {
+			t.Errorf("modelPickerDisplayName(%q, %q) = %q, want %q", tc.id, tc.description, got, tc.want)
+		}
+	}
+}
+
+// Two distinct model ids that share the same catalog description must render as
+// distinct rows (the "duplicate-looking rows" symptom), never as the shared
+// sentence.
+func TestModelPickerDisplayNameDistinctForSharedDescription(t *testing.T) {
+	shared := "Mistral coding agent model for repository tasks and software engineering"
+	a := modelPickerDisplayName("codestral-2", shared)
+	b := modelPickerDisplayName("devstral-2", shared)
+	if a == b {
+		t.Fatalf("shared description collapsed rows to the same title: %q", a)
+	}
+	if a == shared || b == shared {
+		t.Fatalf("row title used the description sentence: a=%q b=%q", a, b)
+	}
+}
+
+// With no id to name the row, a non-generic description is still an acceptable
+// fallback; a generic placeholder (or nothing) falls back to "model".
+func TestModelPickerDisplayNameFallsBackToDescriptionOnlyWithoutID(t *testing.T) {
+	if got := modelPickerDisplayName("", "Friendly Name"); got != "Friendly Name" {
+		t.Fatalf("empty id should fall back to the description, got %q", got)
+	}
+	if got := modelPickerDisplayName("", "catalog default"); got != "model" {
+		t.Fatalf("generic description with no id should yield %q, got %q", "model", got)
+	}
+	if got := modelPickerDisplayName("", ""); got != "model" {
+		t.Fatalf("empty id and description should yield %q, got %q", "model", got)
+	}
+}

internal/tui/permission_deadlock_test.go

@@ -0,0 +1,109 @@
+package tui
+
+import (
+	"context"
+	"testing"
+
+	"github.com/Gitlawb/zero/internal/agent"
+)
+
+func permissionModel(t *testing.T) model {
+	t.Helper()
+	m := newModel(context.Background(), Options{})
+	m.pending = true
+	m.activeRunID = 7
+	m.width = 96
+	return m
+}
+
+// The deadlock: a permission request whose Action is NOT prompt (e.g. a
+// sandbox-allowed command that still blocked to request additional permissions)
+// must be resolved immediately — the agent goroutine is parked awaiting a
+// decision. Before the fix the handler dropped it, and the run hung forever
+// (the reported "stuck for 33 minutes"). Fail closed: a non-prompt allow denies.
+func TestPermissionRequestNonPromptResolvesFailClosed(t *testing.T) {
+	m := permissionModel(t)
+	var got *agent.PermissionDecision
+	decide := func(d agent.PermissionDecision) { got = &d }
+
+	updated, _ := m.Update(permissionRequestMsg{
+		runID:   7,
+		request: agent.PermissionRequest{ToolCallID: "c1", ToolName: "bash", Action: agent.PermissionActionAllow},
+		decide:  decide,
+	})
+	next := updated.(model)
+
+	if got == nil {
+		t.Fatal("DEADLOCK: decide was never called for a non-prompt request — the agent goroutine would park forever")
+	}
+	if got.Action != agent.PermissionDecisionDeny {
+		t.Fatalf("decision = %q, want deny (fail closed — never silently grant an unsurfaced permission)", got.Action)
+	}
+	if next.pendingPermission != nil {
+		t.Fatal("a non-prompt request must not open a pending prompt")
+	}
+}
+
+// A superseded/stale run's request (runID mismatch) must also be resolved
+// (cancelled) so its parked goroutine unblocks instead of depending on
+// context-cancel ordering.
+func TestPermissionRequestStaleRunResolvesCancel(t *testing.T) {
+	m := permissionModel(t) // activeRunID = 7
+	var got *agent.PermissionDecision
+	decide := func(d agent.PermissionDecision) { got = &d }
+
+	m.Update(permissionRequestMsg{
+		runID:   3, // != activeRunID
+		request: agent.PermissionRequest{ToolCallID: "c1", ToolName: "bash", Action: agent.PermissionActionPrompt},
+		decide:  decide,
+	})
+
+	if got == nil {
+		t.Fatal("stale-run request was dropped without resolving — its agent goroutine would park")
+	}
+	if got.Action != agent.PermissionDecisionCancel {
+		t.Fatalf("decision = %q, want cancel for a superseded run", got.Action)
+	}
+}
+
+// An explicit-cancel action is honored as a cancel (not denied).
+func TestPermissionRequestCancelActionResolvesCancel(t *testing.T) {
+	m := permissionModel(t)
+	var got *agent.PermissionDecision
+	decide := func(d agent.PermissionDecision) { got = &d }
+
+	m.Update(permissionRequestMsg{
+		runID:   7,
+		request: agent.PermissionRequest{ToolCallID: "c1", ToolName: "bash", Action: agent.PermissionActionCancel},
+		decide:  decide,
+	})
+	if got == nil || got.Action != agent.PermissionDecisionCancel {
+		t.Fatalf("cancel action must resolve as cancel, got %#v", got)
+	}
+}
+
+// A genuine prompt request stores the pending prompt and does NOT resolve yet —
+// the decision comes from the user's reply. (Regression guard: the fix must not
+// accidentally auto-resolve real prompts.)
+func TestPermissionRequestPromptDefersToUser(t *testing.T) {
+	m := permissionModel(t)
+	resolved := false
+	decide := func(agent.PermissionDecision) { resolved = true }
+
+	updated, _ := m.Update(permissionRequestMsg{
+		runID: 7,
+		request: agent.PermissionRequest{
+			ToolCallID: "c1", ToolName: "bash", Action: agent.PermissionActionPrompt,
+			Reason: "runs a shell command", AvailableDecisions: []agent.PermissionDecisionAction{agent.PermissionDecisionAllow},
+		},
+		decide: decide,
+	})
+	next := updated.(model)
+
+	if resolved {
+		t.Fatal("a real prompt must not be auto-resolved; it awaits the user")
+	}
+	if next.pendingPermission == nil {
+		t.Fatal("a prompt request must open a pending permission prompt")
+	}
+}

internal/tui/picker.go

@@ -452,11 +452,17 @@ func registryModelPickerMeta(entry modelregistry.ModelEntry) string {
 }
 
 func modelPickerDisplayName(id string, description string) string {
-	if description = strings.TrimSpace(description); description != "" && !providerWizardGenericModelDescription(description) {
-		return description
-	}
+	// The row title is the model NAME, not its marketing blurb. Catalog/discovery
+	// descriptions (from models.dev) are full sentences, and several models share
+	// the same one — using them as titles showed sentence-long rows that looked like
+	// exact duplicates and hid the actual id (which only survived in the meta line).
+	// Prefer the (prettified) id; fall back to a non-generic description only when
+	// there is no id to name the row.
 	id = strings.TrimSpace(id)
 	if id == "" {
+		if description = strings.TrimSpace(description); description != "" && !providerWizardGenericModelDescription(description) {
+			return description
+		}
 		return "model"
 	}
 	name := id