feat(website): align the docs index with the control plane

apps/website/e2e/website.spec.ts

@@ -182,10 +182,20 @@ test('docs page renders sidebar and content', async ({ page }) => {
 
 test('docs landing page shows library cards', async ({ page }) => {
   await page.goto('/docs');
-  await expect(page.getByText('LangGraph').first()).toBeVisible();
-  await expect(page.getByText('Render').first()).toBeVisible();
-  await expect(page.getByText('Chat').first()).toBeVisible();
-  await expect(page.getByText('AG-UI').first()).toBeVisible();
+  // Assert on card titles, not page text. A bare getByText('Render') passed on
+  // a substring of "json-render"; hasText on the card would match the Chat
+  // card too, whose blurb mentions json-render. Only the title is the card.
+  const titles = page.locator('.docs-index-card-title');
+  await expect(titles.filter({ hasText: /^LangGraph$/ })).toBeVisible();
+  await expect(titles.filter({ hasText: /^json-render$/ })).toBeVisible();
+  await expect(titles.filter({ hasText: /^AG-UI$/ })).toBeVisible();
+  await expect(titles.filter({ hasText: /^Chat$/ })).toBeVisible();
+});
+
+test('docs landing page carries the control plane', async ({ page }) => {
+  await page.goto('/docs');
+  await expect(page.getByRole('navigation', { name: 'Docs modes' })).toBeVisible();
+  await expect(page.getByRole('button', { name: 'Choose a library' })).toBeVisible();
 });
 
 test('api reference renders in docs', async ({ page }) => {

apps/website/src/app/docs/docs-index-shell.spec.tsx

@@ -0,0 +1,56 @@
+// @vitest-environment jsdom
+import React from 'react';
+import { fireEvent, render, screen, within } from '@testing-library/react';
+import { beforeEach, describe, expect, it, vi } from 'vitest';
+import DocsLandingPage from './page';
+
+vi.mock('next/navigation', () => ({
+  usePathname: () => '/docs',
+  useRouter: () => ({ push: vi.fn() }),
+}));
+
+beforeEach(() => {
+  window.localStorage.clear();
+});
+
+describe('docs index', () => {
+  it('wears the same control plane as every other docs route', () => {
+    render(<DocsLandingPage />);
+
+    const scope = screen.getByRole('heading', { name: 'Scope' }).closest('section');
+    if (!scope) throw new Error('Expected a Scope section');
+    // Library-neutral: the index is where you pick one, so it claims none.
+    expect(within(scope).getByText('Docs')).toBeTruthy();
+    expect(within(scope).getByText('Overview')).toBeTruthy();
+    expect(screen.getByRole('button', { name: 'Choose a library' })).toBeTruthy();
+  });
+
+  it('keeps the landing content out of the prose measure', () => {
+    const { container } = render(<DocsLandingPage />);
+
+    // The card grids need their own width; the [slug] route's md:max-w-3xl
+    // article measure would flatten them into a single column.
+    const body = container.querySelector('.docs-index-body');
+    expect(body).toBeTruthy();
+    expect(body?.className).not.toContain('max-w-3xl');
+  });
+
+  it('calls the render library what the docs call it', () => {
+    render(<DocsLandingPage />);
+
+    // The picker menu is closed on mount, so its labels are not in the DOM
+    // until it is opened. Asserting without this click passes even when
+    // docsConfig still says "Render" — it only ever sees the index card.
+    fireEvent.click(screen.getByRole('button', { name: 'Choose a library' }));
+    const menu = screen.getByRole('menu');
+    const pickerNames = within(menu)
+      .getAllByRole('menuitemradio')
+      .map((item) => item.querySelector('.docs-sidebar-lib-item-title')?.textContent);
+
+    // 85 occurrences of "json-render" across docs content vs one "Render" in
+    // docsConfig. With the control plane on this page both labels are on
+    // screen at once, so they have to agree.
+    expect(pickerNames).toContain('json-render');
+    expect(pickerNames).not.toContain('Render');
+  });
+});

apps/website/src/app/docs/page.tsx

@@ -6,6 +6,9 @@ import { Eyebrow } from '../../components/ui/Eyebrow';
 import { Card } from '../../components/ui/Card';
 import { Pill } from '../../components/ui/Pill';
 import { CopyButton } from '../../components/docs/CopyButton';
+import { DocsControlPlane } from '../../components/docs/DocsControlPlane';
+import { DocsSearch } from '../../components/docs/DocsSearch';
+import { DOCS_INDEX_TITLE } from '../../lib/docs-config';
 import { createPageMetadata } from '../../lib/site-metadata';
 
 export const metadata = createPageMetadata({
@@ -152,7 +155,19 @@ function GlyphChip({ size, children }: { size: number; children: ReactNode }) {
 
 export default function DocsLandingPage() {
   return (
-    <>
+    <div className="flex min-h-screen docs-shell-page">
+      <DocsSearch />
+      {/* The index is library-neutral: it is where you pick one. */}
+      <DocsControlPlane
+        activeLibrary={null}
+        activeSection=""
+        activeSlug=""
+        pageTitle={DOCS_INDEX_TITLE}
+      />
+      {/* Deliberately outside the article measure the [slug] route uses — the
+       * card grids need their own width, and the prose column would flatten
+       * them. The shell supplies the chrome, not the content width. */}
+      <div className="flex-1 min-w-0 docs-shell-body docs-index-body">
 
       {/* Hero */}
       <Section surface="canvas" ariaLabelledBy="docs-heading">
@@ -309,6 +324,7 @@ export default function DocsLandingPage() {
           </div>
         </Container>
       </Section>
-    </>
+      </div>
+    </div>
   );
 }

apps/website/src/components/shared/Nav.spec.tsx

@@ -26,6 +26,21 @@ describe('Docs mobile navigation', () => {
     pathnameRef.current = '/docs/langgraph/guides/streaming';
   });
 
+  it('names the docs index the same way the page does', () => {
+    pathnameRef.current = '/docs';
+    render(<Nav />);
+    fireEvent.click(screen.getByRole('button', { name: 'Open menu' }));
+    const dialog = screen.getByRole('dialog', { name: 'Mobile navigation' });
+
+    // The page passes pageTitle="Overview"; Nav derives its own title. When
+    // they drift, the same page is called two different things depending on
+    // viewport width.
+    const scope = within(dialog).getByRole('heading', { name: 'Scope' }).closest('section');
+    if (!scope) throw new Error('Expected a Scope section');
+    expect(within(scope).getByText('Overview')).toBeTruthy();
+    expect(within(scope).queryByText('Documentation')).toBeNull();
+  });
+
   it('does not invent a library on a library-neutral docs page', () => {
     pathnameRef.current = '/docs/choosing-an-adapter';
     render(<Nav />);

apps/website/src/components/shared/Nav.tsx

@@ -3,6 +3,7 @@ import { useState, useEffect, useRef, useCallback } from 'react';
 import Link from 'next/link';
 import { usePathname } from 'next/navigation';
 import {
+  DOCS_INDEX_TITLE,
   findDocsPage,
   getLibraryConfig,
   specialDocsPages,
@@ -108,7 +109,7 @@ export function Nav() {
   const docsPageTitle =
     findDocsPage(activeLibrary, activeSection, activeSlug)?.title ??
     specialDocsPage?.title ??
-    'Documentation';
+    (pathname === '/docs' ? DOCS_INDEX_TITLE : 'Documentation');
   const navRef = useRef<HTMLElement>(null);
   const mobileTriggerRef = useRef<HTMLButtonElement>(null);
   const mobileDialogRef = useRef<HTMLDivElement>(null);

apps/website/src/lib/docs-config.ts

@@ -62,6 +62,13 @@ export interface SpecialDocsPage {
   description: string;
 }
 
+/**
+ * What the docs root calls itself in the control plane's Scope card. Shared so
+ * the page and the mobile drawer, which resolve the title independently,
+ * cannot drift into naming the same page two different things.
+ */
+export const DOCS_INDEX_TITLE = 'Overview';
+
 export const specialDocsPages: SpecialDocsPage[] = [
   {
     path: '/docs/choosing-an-adapter',
@@ -133,7 +140,9 @@ export const docsConfig: DocsLibrary[] = [
   },
   {
     id: 'render',
-    title: 'Render',
+    // Display label only. The package is @threadplane/render and the docs URL
+    // stays /docs/render/ — but every page of prose calls it json-render.
+    title: 'json-render',
     description: 'Declarative UI rendering from JSON specifications',
     group: 'library',
     sections: [

docs/superpowers/specs/2026-09-01-docs-index-control-plane-design.md

@@ -0,0 +1,85 @@
+# Aligning the docs index with the control plane
+
+**Date:** 2026-09-01
+**Scope:** `/docs`, and the `Render` / `json-render` naming split
+**Status:** approved, ready to implement
+
+## Context
+
+After #920, `/docs` is the only `/docs/*` route without the control plane. That
+was a deliberate call at the time — it is a designed landing page, and forcing
+its 2-up card grids into the prose column would flatten it. In review the
+inconsistency was judged worse than that risk, so the page adopts the shell.
+
+## Design
+
+### The shell, without the prose measure
+
+`/docs` renders `docs-shell-page` with `<DocsControlPlane activeLibrary={null}>`,
+reusing the library-neutral state added in #920.
+
+The landing content goes inside `docs-shell-body` but **not** inside the
+`md:max-w-3xl` article measure the `[slug]` route uses. Its `Section`/`Container`
+structure keeps its own width. The chrome becomes consistent; the layout does
+not get squeezed.
+
+Scope reads `Docs / Overview`. Passing the page title verbatim would render
+`Docs / Documentation`, which is redundant.
+
+`Nav` resolves the drawer's title independently of the page, so setting this on
+the page alone made the desktop say `Docs / Overview` while the mobile drawer
+said `Docs / Documentation` — the same page named two ways by viewport width.
+Both now read a shared `DOCS_INDEX_TITLE` constant so they cannot drift.
+
+### The picker stays, deliberately
+
+The page's main content *is* a backend picker, so the sidebar picker is
+arguably duplicative — the same class of problem removed in #911, where the
+library was stated twice.
+
+Kept anyway, because the two do different jobs: the cards are a decision aid
+(compare, copy the install line, follow the quickstart), the picker is a
+shortcut for a returning reader who already knows where they are going. The
+#911 duplication was two *statements of the same fact*; this is a statement and
+a shortcut.
+
+### `Render` → `json-render`
+
+The library is called `json-render` 85 times across docs content and on the
+marketing page, and on the `/docs` card. It is called `Render` in exactly one
+place: `docsConfig[].title`, which feeds the picker, breadcrumbs, structured
+data and search.
+
+Once the index has the control plane, both names appear on screen at once — the
+sidebar saying `Render`, the card saying `json-render`.
+
+`docsConfig` title becomes `json-render`. The package stays
+`@threadplane/render` and the URL stays `/docs/render/`; only the display label
+changes. Marketing surfaces (`/render`, the footer, `solutions-data`) keep
+`Render` — those describe the product page, a different context, and are not
+part of this alignment.
+
+### Test hygiene
+
+`e2e/website.spec.ts` → `'docs landing page shows library cards'` asserts
+`getByText('Render')`, which passes on a substring of `json-render` and would
+also pass on the new sidebar. It is tightened to assert the cards themselves.
+
+## Testing
+
+1. **The index renders the control plane** with a library-neutral Scope of
+   `Docs / Overview` and a `Choose a library` picker.
+2. **The picker reads `json-render`**, not `Render`.
+3. **The landing content keeps its width** — it is not inside the article
+   measure.
+4. **The drawer and the page agree on the index's name.**
+
+Each guard was mutation-tested. The naming test initially passed against a
+reverted `docsConfig` — `getAllByText` is exact-match and the picker menu is
+closed on mount, so it only ever saw the index card. It now opens the menu
+first.
+
+## Out of scope
+
+Marketing surfaces keep `Render`. Renaming those is a product-vocabulary
+decision about the `/render` page, not about docs consistency.