@@ -0,0 +1,14 @@
+---
+'@object-ui/app-shell': patch
+'@object-ui/i18n': patch
+---
+
+fix(app-shell,i18n): on a deployment with no AI agent, Home's build chip opens Studio's new-package flow as "New in Studio", and `/ai` says no assistant is enabled instead of redirecting home
+
+Clause-②: yes
+Metadata-protocol: none
+
+- **Home's build chip reads the agent catalog.** On a deployment whose catalog (`GET /api/v1/ai/agents`) is empty or absent, the greeting row's "Build an app" (「构建应用」) promised a build nothing there could start. There it now reads "New in Studio" (「在 Studio 中新建」) and opens Studio's new-package flow; a session that may not author gets no build chip at all, while "Start with a template" keeps the reason. The chip waits for the catalog's answer, so neither form flashes first. With an agent in the catalog nothing changes.
+- **`/ai` with no agent.** `RequireAiSurface` used to redirect a visit to `/ai` home with no word of why. It now shows the AI-unavailable screen in place (「AI 助手不可用」 · 「当前部署未启用 AI 助手。其他功能一切正常。」), with the way home and, for an admin who may author on a runtime that offers authoring, the same "New in Studio" link. The screen is the one `AiChatPage` already showed for an empty catalog, now its own module (`console/ai/AiUnavailable.tsx`) shared by both. `RequireAiSurface`'s `redirectTo` prop keeps its name and now sets where that screen's way home leads.
+- **Studio deep link.** `/studio?new=package` opens the Studio landing with the create-package dialog open, and drops the param from the address. `STUDIO_NEW_PACKAGE_PATH` (`views/studio-design/studioNewPackage.ts`) is its one spelling.
+- **i18n.** New key `home.build.inStudio` in all ten packs.
@@ -396,10 +396,10 @@ export function App() {
 
               `RequireAiSurface` keeps these from dead-ending on a runtime that
               serves no AI (Community Edition): with AI unavailable a stale
-              bookmark / external link redirects to home instead of mounting a
-              chat with no agent to talk to. Cloud installs pass straight
-              through. Purely additive runtime gating — same server signal the
-              floating-chat FAB has always used.
+              bookmark / external link gets a screen saying so, with the way
+              home, instead of a chat with no agent to talk to. Cloud installs
+              pass straight through. Purely additive runtime gating — same
+              server signal the floating-chat FAB has always used.
             */}
             <Route path="/ai" element={
               <ProtectedRoute>
 
@@ -128,10 +128,10 @@ export function RequireStudioAccess({
    * DECLARED landing (objectui#7373), which is the environment launcher
    * wherever no app declares one; an explicit value still wins.
    *
-   * It was `redirectTo` while a non-holder was redirected there, the posture of
-   * `RequireAiSurface`, which still redirects: a runtime that serves no agent
-   * has nothing to refuse, and what reaches it is a stale link. A non-holder
-   * here is refused a capability, and is now told so (objectui#12035).
+   * It was `redirectTo` while a non-holder was redirected there. A non-holder
+   * here is refused a capability, and is now told so (objectui#12035);
+   * `RequireAiSurface` later took the same posture for a runtime that serves
+   * no agent (objectstack#26614).
    */
   homeTo?: string;
 }) {
 
@@ -1218,8 +1218,8 @@ export function AppContent({ extraRoutes, extraRoutesNoApp }: AppContentProps =
   // that leave the router — see `organizations/resolveHomeUrl.ts`). Both the
   // declared landing and the launcher fallback are
   // part of the outer skeleton every host that mounts this component provides
-  // (see this file's header), and `RequireAiSurface` in `ConsoleShell.tsx`
-  // already bounces the same way for a surface this runtime cannot serve.
+  // (see this file's header), and the no-assistant screen `RequireAiSurface`
+  // in `ConsoleShell.tsx` shows leads home the same way.
   //
   // Telling "you may not enter THIS app" apart from "this app is not published"
   // is the other half of #4473 and stays gated on the backend permission-denied
 
@@ -11,7 +11,7 @@
  */
 
 import { Suspense, useEffect, useRef, useState, type ReactNode } from 'react';
-import { Navigate, useLocation } from 'react-router-dom';
+import { Navigate, useLocation, useNavigate } from 'react-router-dom';
 import { AuthGuard, useAuth, createAuthenticatedFetch } from '@object-ui/auth';
 import { useObjectTranslation } from '@object-ui/i18n';
 import { SchemaRendererProvider, ActionProvider, NotificationProvider, HostMapStyleProvider } from '@object-ui/react';
@@ -31,6 +31,7 @@ import { appRouteSegment } from '../utils/appRoute.js';
 import { SETUP_APP_PACKAGE_ID, SETUP_APP_NAME } from './setupApp.js';
 import { useAiSurfaceEnabled } from '../hooks/useAiSurface.js';
 import { useHomePath } from '../hooks/useHomePath.js';
+import { AiUnavailable } from './ai/AiUnavailable.js';
 import { PreviewModeProvider } from '../preview/PreviewModeContext.js';
 import { NavigationProvider } from '../context/NavigationContext.js';
 import { FavoritesProvider } from '../context/FavoritesProvider.js';
@@ -457,38 +458,50 @@ export function RequireOrganization({ children }: { children: ReactNode }) {
  * RequireAiSurface — gate for the `/ai*` routes. The console is edition-agnostic
  * (MIT, runtime-gated): a Community Edition runtime serves no AI agent, so a
  * stale `/ai` bookmark or external link must not land on a broken/empty chat.
- * When the server serves no agent it redirects to `redirectTo` (home) instead.
+ * When the server serves no agent it shows `AiUnavailable` in place of the
+ * chat: one line saying this deployment has no AI assistant enabled, the way
+ * home, and Studio's new-package flow for a session that may author.
+ *
+ * It used to redirect home there (objectstack#26614), which read exactly like
+ * a broken link: the visitor arrived on Home with no word of why. Saying so in
+ * place is the posture `RequireStudioAccess` took for the same reason
+ * (objectui#12035), and the URL stays.
  *
  * Availability is the live agent catalog (see {@link useAiSurfaceEnabled}) — the
  * same signal every other AI entry point now gates on, so the route is reachable
- * from exactly the entry points that are visible (no shown CTA that bounces back
- * to home, no hidden FAB to a working route). Waits for the catalog to resolve
- * before deciding so the redirect never flashes on first paint.
+ * from exactly the entry points that are visible (no hidden FAB to a working
+ * route). Waits for the catalog to resolve before deciding, so the screen never
+ * flashes on first paint.
  *
- * WHICH home it bounces to is the DECLARED landing (objectui#7373), resolved by
- * `useHomePath()` — the default is no longer the launcher literal. A caller that
- * passes `redirectTo` still wins, and on a deployment that declares no landing
- * the hook answers the launcher, so every ordinary environment is unchanged.
+ * WHERE the screen's way home leads is the DECLARED landing (objectui#7373),
+ * resolved by `useHomePath()`; a caller that passes `redirectTo` still wins.
+ * The prop keeps the name it had while this gate redirected there, because
+ * renaming a published prop breaks every host that passes it.
  */
 export function RequireAiSurface({
   children,
   redirectTo,
 }: {
   children: ReactNode;
-  /** Overrides the declared-home default. */
+  /** Where the no-assistant screen's way home leads; overrides the declared home. */
   redirectTo?: string;
 }) {
   const homePath = useHomePath();
+  const navigate = useNavigate();
+  const { t } = useObjectTranslation();
   const { enabled, isLoading } = useAiSurfaceEnabled();
   if (isLoading) return <LoadingFallback />;
-  // Splash-preserving handoff (objectui#6507). This is a BOOT-path redirect
-  // even though `/ai` is reachable from inside the console: every in-app entry
-  // point gates on this same `useAiSurfaceEnabled` signal (`AppHeader`'s
-  // assistant button, `ConsoleLayout`'s dock, `HomeLayout`/`HomePage`), so on a
-  // runtime where this branch fires none of them is rendered. What reaches it
-  // is a stale bookmark or an external link — a first navigation, with the
-  // splash still up and no layout underneath.
-  if (!enabled) return <RedirectWithSplash to={redirectTo ?? homePath} replace />;
+  // The full-viewport frame the boot splash hands off to: what reaches this
+  // branch is a first navigation (every in-app entry point gates on this same
+  // signal, so none is rendered on such a runtime), with no layout underneath
+  // (objectui#6507).
+  if (!enabled) {
+    return (
+      <div className="flex h-screen flex-col bg-background" data-testid="ai-surface-unavailable">
+        <AiUnavailable hasError={false} onHome={() => navigate(redirectTo ?? homePath)} t={t} />
+      </div>
+    );
+  }
   return <>{children}</>;
 }
 
 
@@ -1,6 +1,7 @@
 import { describe, it, expect, vi, beforeEach } from 'vitest';
 import React from 'react';
 import { render, screen } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
 import { MemoryRouter, Routes, Route } from 'react-router-dom';
 import { MetadataCtx, type MetadataContextValue } from '@object-ui/react';
 import { RequireAiSurface } from '../ConsoleShell';
@@ -13,6 +14,29 @@ vi.mock('../../hooks/useAiSurface', () => ({
 }));
 const mockSurface = vi.mocked(useAiSurfaceEnabled);
 
+/**
+ * Who is looking, and whether this runtime offers authoring: the three terms
+ * the no-assistant screen offers Studio's new-package flow on.
+ */
+const viewer = vi.hoisted(() => ({ isAdmin: true, canAuthorMetadata: true, aiStudio: true }));
+vi.mock('@object-ui/auth', async (importOriginal) => ({
+  ...(await importOriginal<Record<string, unknown>>()),
+  useWorkspaceAdminStatus: () => ({ isAdmin: viewer.isAdmin, isResolved: true }),
+}));
+vi.mock('../../hooks/useCanAuthorMetadata', async (importOriginal) => ({
+  ...(await importOriginal<Record<string, unknown>>()),
+  useCanAuthorMetadata: () => viewer.canAuthorMetadata,
+}));
+vi.mock('../../runtime-config', async (importOriginal) => ({
+  ...(await importOriginal<Record<string, unknown>>()),
+  isAiStudioEnabled: () => viewer.aiStudio,
+}));
+// `t` echoes the key, so a hardcoded string fails here.
+vi.mock('@object-ui/i18n', async (importOriginal) => ({
+  ...(await importOriginal<Record<string, unknown>>()),
+  useObjectTranslation: () => ({ t: (key: string) => `«${key}»`, language: 'en' }),
+}));
+
 /**
  * The app list this guard's home target is resolved from (objectui#7373).
  * `undefined` renders the guard with no metadata context at all — the shape
@@ -59,6 +83,9 @@ function renderGuardedAi(apps?: MetadataContextValue['apps']) {
 describe('RequireAiSurface', () => {
   beforeEach(() => {
     mockSurface.mockReturnValue({ enabled: true, isLoading: false });
+    viewer.isAdmin = true;
+    viewer.canAuthorMetadata = true;
+    viewer.aiStudio = true;
   });
 
   it('renders the AI surface when the server serves agents (cloud install)', () => {
@@ -67,41 +94,73 @@ describe('RequireAiSurface', () => {
     expect(screen.queryByText('HOME')).not.toBeInTheDocument();
   });
 
-  it('redirects to home when no agents are served (Community Edition) — no dead-end chat', () => {
+  it('says in place that no assistant is enabled when no agents are served (objectstack#26614)', () => {
+    // Community Edition. It used to redirect home, which read like a broken
+    // link; now the URL stays and the screen says why, with the way home.
     mockSurface.mockReturnValue({ enabled: false, isLoading: false });
     renderGuardedAi();
     expect(screen.queryByText('AI CHAT')).not.toBeInTheDocument();
-    expect(screen.getByText('HOME')).toBeInTheDocument();
+    expect(screen.queryByText('HOME')).not.toBeInTheDocument();
+    const page = screen.getByTestId('ai-unavailable');
+    expect(page).toHaveTextContent('«console.ai.unavailableDescription»');
+    expect(screen.getByTestId('ai-unavailable-home')).toHaveTextContent('«console.ai.unavailableHome»');
+    // Nothing failed, so nothing is offered again.
+    expect(screen.queryByTestId('ai-unavailable-retry')).toBeNull();
+  });
+
+  it('offers Studio\'s new-package flow to a session that may author (objectstack#26614)', () => {
+    mockSurface.mockReturnValue({ enabled: false, isLoading: false });
+    renderGuardedAi();
+    const studio = screen.getByTestId('ai-unavailable-studio');
+    expect(studio).toHaveTextContent('«home.build.inStudio»');
+    expect(studio).toHaveAttribute('href', '/studio?new=package');
+  });
+
+  it.each([
+    ['a non-admin', () => { viewer.isAdmin = false; }],
+    ['a session without the authoring capability', () => { viewer.canAuthorMetadata = false; }],
+    ['a runtime that offers no authoring', () => { viewer.aiStudio = false; }],
+  ])('offers no Studio link to %s (objectstack#26614)', (_who, arrange) => {
+    arrange();
+    mockSurface.mockReturnValue({ enabled: false, isLoading: false });
+    renderGuardedAi();
+    expect(screen.getByTestId('ai-unavailable')).toBeInTheDocument();
+    expect(screen.queryByTestId('ai-unavailable-studio')).toBeNull();
   });
 
-  it('waits (neither chat nor redirect) while the agent catalog is still resolving', () => {
+  it('waits (neither chat nor the no-assistant screen) while the agent catalog is still resolving', () => {
     mockSurface.mockReturnValue({ enabled: false, isLoading: true });
     renderGuardedAi();
     expect(screen.queryByText('AI CHAT')).not.toBeInTheDocument();
+    expect(screen.queryByTestId('ai-unavailable')).not.toBeInTheDocument();
     expect(screen.queryByText('HOME')).not.toBeInTheDocument();
   });
 
-  it('bounces to the DECLARED landing, not the launcher, where one is declared (objectui#7373)', () => {
+  it('leads home to the DECLARED landing, not the launcher, where one is declared (objectui#7373)', async () => {
     // The card's case, on this guard: a stale `/ai` bookmark opened against a
     // control plane that serves no agent. Pre-#7373 the default was the `/home`
     // literal, so the customer landed among environment cards that cannot act
     // on anything their deployment has. This pin fails on that implementation.
+    const user = userEvent.setup();
     mockSurface.mockReturnValue({ enabled: false, isLoading: false });
     renderGuardedAi([
       { name: 'cloud_control', label: 'Cloud', isDefault: true },
       { name: 'account', label: 'Account' },
     ]);
+    await user.click(screen.getByTestId('ai-unavailable-home'));
     expect(screen.getByText('DECLARED LANDING')).toBeInTheDocument();
     expect(screen.queryByText('HOME')).not.toBeInTheDocument();
   });
 
-  it('keeps the launcher for an ordinary environment that declares nothing', () => {
+  it('keeps the launcher for an ordinary environment that declares nothing', async () => {
     // The status quo, stated as its own case so the two answers cannot be
     // confused for one: an app list WITHOUT a declaration still resolves to the
     // launcher, and so does a guard mounted outside a metadata provider (every
     // other case in this file).
+    const user = userEvent.setup();
     mockSurface.mockReturnValue({ enabled: false, isLoading: false });
     renderGuardedAi([{ name: 'crm', label: 'CRM' }, { name: 'setup', label: 'Setup' }]);
+    await user.click(screen.getByTestId('ai-unavailable-home'));
     expect(screen.getByText('HOME')).toBeInTheDocument();
     expect(screen.queryByText('DECLARED LANDING')).not.toBeInTheDocument();
   });
 
@@ -192,7 +192,11 @@ describe('boot-gate coverage — ConsoleShell (objectui#6507)', () => {
     expectCovered(reading, 'RequireOrganization (no org, multi-org on)');
   });
 
-  it('RequireAiSurface :382 — the runtime serves no agent', async () => {
+  it('RequireAiSurface — the runtime serves no agent', async () => {
+    // No redirect any more (objectstack#26614): the gate shows its
+    // no-assistant screen in place. The deciding commit must still hand the
+    // splash to something that covers the viewport, which that screen's
+    // full-height frame does.
     aiSurface = { enabled: false, isLoading: false };
     const reading = await coverageAt(
       '/ai',
 
@@ -44,9 +44,6 @@ import {
   SheetDescription,
   SheetHeader,
   SheetTitle,
-  Empty,
-  EmptyTitle,
-  EmptyDescription,
   DropdownMenu,
   DropdownMenuTrigger,
   DropdownMenuContent,
@@ -143,6 +140,7 @@ import { BuildDebugDrawer } from './BuildDebugDrawer.js';
 import { isConversationZh } from './conversationLanguage.js';
 import { resolveOutboundAgentText, type OutboundAgentTextKey } from './outboundAgentText.js';
 import { resolveApiBase } from './resolveApiBase.js';
+import { AiUnavailable } from './AiUnavailable.js';
 
 function partString(part: HydratedUIMessagePart, key: string): string | undefined {
   const value = part[key];
@@ -944,8 +942,8 @@ export function AiChatPage({ apiBase: apiBaseProp, defaultAgent: defaultAgentPro
     useAgents({ apiBase });
   const catalogNames = useMemo(() => agents.map((a) => a.name), [agents]);
   // Catalog resolved with no agent to talk to. The `/ai` route guard already
-  // redirects when discovery reports AI unavailable (Community Edition), so this
-  // is the secondary safety net: a deployment that reports AI enabled but serves
+  // shows `AiUnavailable` itself when the runtime serves no agent (Community
+  // Edition), so this is the secondary safety net: a deployment that reports AI enabled but serves
   // no agent (misconfig), a transient `/agents` failure, or a `VITE_AI_BASE_URL`
   // server that returns an empty list. Either way, degrade to a graceful state
   // instead of the agent-less echo chat (autoResponse) that ChatPane falls into.
@@ -1527,56 +1525,6 @@ export function AiChatPage({ apiBase: apiBaseProp, defaultAgent: defaultAgentPro
   );
 }
 
-/**
- * Graceful state for `/ai` when the agent catalog resolved empty — shown
- * instead of an agent-less echo chat. `hasError` distinguishes "AI not enabled
- * on this deployment" (Community Edition) from "couldn't reach the AI service"
- * (offline/misconfig), which also offers a retry. Either way there's a way out
- * (back to home), so the route never dead-ends.
- */
-function AiUnavailable({
-  hasError,
-  onRetry,
-  onHome,
-  t,
-}: {
-  hasError: boolean;
-  onRetry: () => void;
-  onHome: () => void;
-  t: (key: string, options?: Record<string, unknown>) => string;
-}) {
-  return (
-    <div className="flex flex-1 items-center justify-center p-6" data-testid="ai-unavailable">
-      <Empty>
-        <EmptyTitle>
-          {t('console.ai.unavailableTitle', { defaultValue: 'AI assistant unavailable' })}
-        </EmptyTitle>
-        <EmptyDescription>
-          {hasError
-            ? t('console.ai.unavailableError', {
-                defaultValue:
-                  "Couldn't reach the AI service. It may be temporarily offline — try again, or head back home.",
-              })
-            : t('console.ai.unavailableDescription', {
-                defaultValue:
-                  "This deployment doesn't have an AI assistant enabled. Everything else works as usual.",
-              })}
-        </EmptyDescription>
-        <div className="mt-6 flex flex-col items-center gap-3 sm:flex-row">
-          {hasError && (
-            <Button variant="outline" onClick={onRetry} data-testid="ai-unavailable-retry">
-              {t('console.ai.unavailableRetry', { defaultValue: 'Try again' })}
-            </Button>
-          )}
-          <Button onClick={onHome} data-testid="ai-unavailable-home">
-            {t('console.ai.unavailableHome', { defaultValue: 'Back to home' })}
-          </Button>
-        </div>
-      </Empty>
-    </div>
-  );
-}
-
 interface ChatPaneProps {
   /**
    * cloud#1610 — what the user is currently discussing, derived by the HOST