feat: redesign Sidebar with hierarchical trees, starring, and collapsible sections

Replace flat app/route/agent lists with expandable tree navigation. Apps contain their routes and agents hierarchically. Add localStorage- backed starring with composite keys for uniqueness. Persist expand state to sessionStorage across page navigations. Add collapsible section headers, remove button on starred items, and parent app context labels. Create stub pages for /apps/:id, /agents/:id, /admin, /api-docs. Consolidate duplicated sidebar data into shared mock. Widen sidebar from 220px to 260px. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-18 17:50:41 +01:00
parent 4aeb5be6ab
commit e69e5ab5fe
23 changed files with 1809 additions and 484 deletions
--- a/.claude/settings.local.json
+++ b/.claude/settings.local.json
@@ -0,0 +1,21 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(bash \"C:/Users/Hendrik/.claude/plugins/cache/claude-plugins-official/superpowers/5.0.4/skills/brainstorming/scripts/start-server.sh\" --project-dir \"C:/Users/Hendrik/Documents/projects/design-system\")",
+      "Bash(npm create:*)",
+      "Bash(node:*)",
+      "Bash(npm show:*)",
+      "Bash(npm install:*)",
+      "Bash(npm audit:*)",
+      "Bash(timeout 10 npm run dev)",
+      "Bash(npx vitest:*)",
+      "Bash(npx tsc:*)",
+      "Bash(npm run:*)",
+      "Bash(find C:/Users/Hendrik/Documents/projects/design-system/.worktrees/gap-fill -name *.test.tsx)",
+      "Bash(echo \"EXIT:$?\")",
+      "Bash(bash \"C:\\\\Users\\\\Hendrik\\\\.claude\\\\plugins\\\\cache\\\\claude-plugins-official\\\\superpowers\\\\5.0.4\\\\scripts\\\\start-server.sh\" --project-dir \"C:\\\\Users\\\\Hendrik\\\\Documents\\\\projects\\\\design-system\")",
+      "Bash(echo \"EXIT_CODE=$?\")",
+      "Bash(echo \"EXIT=$?\")"
+    ]
+  }
+}
--- a/COMPONENT_GUIDE.md
+++ b/COMPONENT_GUIDE.md
@@ -34,10 +34,10 @@
 - Removable label → **Tag**

 ### "I need navigation"
- App-level sidebar nav → **Sidebar** (via AppShell)
+- App-level sidebar nav → **Sidebar** (via AppShell) — hierarchical trees with starring
 - Breadcrumb trail → **Breadcrumb**
 - Paginated data → **Pagination** (standalone) or **DataTable** (built-in pagination)
- Hierarchical tree navigation → **TreeView**
+- Hierarchical tree navigation → **TreeView** (generic) or **SidebarTree** (sidebar-specific, internal)

 ### "I need floating content"
 - Tooltip on hover → **Tooltip**
@@ -186,7 +186,7 @@ TreeView for hierarchical data (Application → Routes → Processors)
 | Component | Purpose |
 |-----------|---------|
 | AppShell | Page shell: sidebar + topbar + main + optional detail panel |
-| Sidebar | App navigation with apps, routes, agents sections |
+| Sidebar | Hierarchical navigation with Applications/Agents trees, starring, search filter, bottom links. Props: `apps: SidebarApp[]` (hierarchical — apps contain routes and agents) |
 | TopBar | Header bar with breadcrumb, environment, user info |

 ## Import Paths
--- a/docs/superpowers/specs/2026-03-18-sidebar-redesign.md
+++ b/docs/superpowers/specs/2026-03-18-sidebar-redesign.md
@@ -0,0 +1,307 @@
+# Sidebar Redesign — Hierarchical Navigation with Starring
+
+## Context
+
+The Cameleer3 Sidebar currently renders flat lists of applications, routes, and agents as separate sections. This doesn't reflect the hierarchical relationship in Apache Camel where routes and agents belong to applications. The redesign restructures navigation into expandable trees, adds a starring/favorites system, and adds bottom navigation links (Admin, API Docs).
+
+This project is primarily a design system with a mock application showcasing how all pieces come together. Stub pages will be created for new routes to demonstrate the full navigation flow.
+
+## Sidebar Structure
+
+```
+┌─────────────────────────┐
+│  cameleer  v3.2.1       │  Logo (fixed)
+├─────────────────────────┤
+│  Filter...              │  Search (fixed)
+├─────────────────────────┤
+│  NAVIGATION             │  Section header
+│                         │
+│  ▾ Applications         │  Tree (expandable)
+│    ● order-svc    1.2k  │    App (health dot + exchangeCount)
+│      ▶ ingest      540  │    Route (arrow + exchangeCount)
+│      ▶ notify      320  │
+│    ● payment-svc   800  │
+│      ▶ validate    800  │
+│                         │
+│  ▾ Agents               │  Tree (expandable)
+│    ● order-svc  2/3 live│    App (health dot + live count)
+│      agent-1    42 tps  │    Agent (name + tps)
+│      agent-2    38 tps  │
+│    ● payment-svc 1/1 ...│
+│      agent-3    12 tps  │
+│                         │
+│  ▦ Dashboards           │  Standalone nav link (not a tree node)
+│         ↕ scrollable    │
+├─────────────────────────┤
+│  ★ STARRED              │  Section header (hidden when empty)
+│  Applications           │  Group label
+│    ● order-svc          │
+│  Routes                 │  Group label
+│    ▶ ingest             │
+│  Agents                 │  Group label
+│    agent-prod-1         │
+│         ↕ scrollable    │
+├─────────────────────────┤
+│  ⚙ Admin                │  Bottom link → /admin (fixed)
+│  📄 API Docs            │  Bottom link → /api-docs (fixed)
+└─────────────────────────┘
+```
+
+**Width:** 220px (unchanged)
+
+**Scroll regions:**
+- Navigation: `flex: 1; overflow-y: auto; min-height: 0`
+- Starred: `max-height: 30vh; overflow-y: auto` (entire section hidden when no items are starred)
+- Logo, Search, Bottom: fixed (`flex-shrink: 0`)
+
+## Data Model
+
+### New interfaces (replace current flat App/Route/Agent)
+
+```ts
+interface SidebarApp {
+  id: string
+  name: string
+  health: 'live' | 'stale' | 'dead'
+  exchangeCount: number
+  routes: SidebarRoute[]
+  agents: SidebarAgent[]
+}
+
+interface SidebarRoute {
+  id: string
+  name: string
+  exchangeCount: number
+}
+
+interface SidebarAgent {
+  id: string
+  name: string
+  status: 'live' | 'stale' | 'dead'
+  tps: string
+}
+
+interface SidebarProps {
+  apps: SidebarApp[]
+  activeItemId?: string   // highlighted item; derived from URL if omitted
+  className?: string
+}
+```
+
+**Key changes from current:**
+- Routes and agents nested inside apps (was: three flat arrays)
+- `onItemClick` removed — Sidebar navigates internally via `useNavigate()`
+- Active item derived from `useLocation().pathname` if `activeItemId` not provided
+- Route health is out of scope — routes show a static arrow icon (no StatusDot)
+
+### Agent type migration
+
+The current `src/mocks/agents.ts` has `AgentHealth extends Agent` where `Agent` is imported from Sidebar. Since `SidebarAgent` is now a minimal type (just id, name, status, tps), `AgentHealth` must become self-contained:
+
+```ts
+// src/mocks/agents.ts — no longer extends Sidebar's Agent type
+export interface AgentHealth {
+  id: string
+  name: string
+  service: string
+  version: string
+  tps: string
+  lastSeen: string
+  status: 'live' | 'stale' | 'dead'
+  errorRate?: string
+  uptime: string
+  memoryUsagePct: number
+  cpuUsagePct: number
+  activeRoutes: number
+  totalRoutes: number
+}
+```
+
+## Components
+
+### SidebarTree (`src/design-system/layout/Sidebar/SidebarTree.tsx`)
+
+A sidebar-specific tree component. NOT the generic TreeView — optimized for sidebar rendering with health dots, count badges, and star buttons.
+
+**Props:**
+```ts
+interface SidebarTreeNode {
+  id: string
+  label: string
+  icon?: ReactNode         // StatusDot, arrow icon, etc.
+  badge?: string           // right-aligned text ("1.2k", "42 tps", "2/3 live")
+  path?: string            // navigation path on click
+  starrable?: boolean      // whether star toggle appears (default false)
+  children?: SidebarTreeNode[]
+}
+
+interface SidebarTreeProps {
+  nodes: SidebarTreeNode[]
+  selectedId?: string
+  isStarred: (id: string) => boolean
+  onToggleStar: (id: string) => void
+  onNavigate?: (path: string) => void
+  className?: string
+  filterQuery?: string     // when set, auto-expands matching parents
+}
+```
+
+**Styling:** All SidebarTree styles go in `Sidebar.module.css` (SidebarTree is a private component of Sidebar, not independently used).
+
+**Behaviors:**
+- **Expand/collapse:** Chevron click only. Row click navigates (if `path` set).
+- **Parent nodes without `path`:** Click does nothing (only chevron toggles). The "Applications" and "Agents" root headers are not clickable or starrable — they're just section labels with a toggle chevron.
+- **Star toggle:** Star icon appears on hover (right side, after badge). Filled star always visible on starred items. Click stops propagation (doesn't navigate).
+- **Leaf nodes with no children:** Render without chevron. App nodes with empty `routes[]` or `agents[]` render as leaf nodes (no expand arrow).
+- **Search filter:** When `filterQuery` is set, only nodes matching the query (or with matching descendants) are shown. Matching parents auto-expand. When no matches, the tree is empty (the Sidebar shows a "No results" message).
+- **Keyboard nav:** ArrowUp/Down to move focus, ArrowRight to expand, ArrowLeft to collapse, Enter to navigate/select, Home/End to jump.
+- **ARIA:** `role="tree"`, `role="treeitem"`, `aria-expanded`, `aria-selected`.
+- **Styling:** Uses `--sidebar-*` CSS tokens. Active item gets amber highlight.
+
+### useStarred (`src/design-system/layout/Sidebar/useStarred.ts`)
+
+```ts
+function useStarred(): {
+  starredIds: Set<string>
+  isStarred: (id: string) => boolean
+  toggleStar: (id: string) => void
+}
+```
+
+- Reads/writes `localStorage` key `"cameleer:starred"` (JSON string array)
+- Returns a `Set<string>` for O(1) lookups
+- `toggleStar` updates both React state and localStorage
+- **Error handling:** Wraps `localStorage` read/write in try/catch — falls back to in-memory state if localStorage is unavailable (private browsing, quota exceeded)
+- Cross-tab sync is out of scope for now
+
+### Sidebar (rewritten)
+
+The Sidebar assembles the SidebarTree data from `SidebarApp[]` props:
+
+1. **Applications tree:** Maps each app to a parent node with route children. App nodes show `StatusDot` + name + exchangeCount badge. Route nodes show arrow icon + name + exchangeCount badge. Both apps and routes are `starrable: true`.
+
+2. **Agents tree:** Maps each app to a parent node with agent children. App nodes show `StatusDot` + name + "X/Y live" badge (computed: count agents where `status === 'live'` / total agents). Agent nodes show name + tps badge. Both apps and agents are `starrable: true`.
+
+3. **Dashboards:** A standalone nav link (not part of any tree), rendered as a simple clickable row below the trees. Uses `▦` icon. Note: the current top-level Metrics and Agents nav links are intentionally removed — Metrics will be displayed contextually within app/route/agent detail views, and Agents are accessible via the Agents tree.
+
+4. **Starred section:** Reads `starredIds` from `useStarred()`, looks up items in the apps data, groups by type (Applications, Routes, Agents in that order). Orphaned IDs (starred item no longer in data) are silently ignored. If a starred app appears in both the Applications and Agents trees, it shows only under "Applications" in the starred section. The entire section (header + content) is hidden when no items are starred.
+
+5. **Search:** Filters both trees. When query matches a route/agent name, its parent app stays visible and auto-expands. Placeholder text: "Filter...". On clear, restore previous expand/collapse state.
+
+## Star Icon
+
+Inline SVG (no icon library). Outline star for unstarred, filled star for starred. Amber color (`var(--amber)`).
+
+```html
+<!-- outline (unstarred) -->
+<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2">
+  <path d="M12 2l3.09 6.26L22 9.27l-5 4.87 1.18 6.88L12 17.77l-6.18 3.25L7 14.14 2 9.27l6.91-1.01L12 2z"/>
+</svg>
+
+<!-- filled (starred) -->
+<svg width="14" height="14" viewBox="0 0 24 24" fill="currentColor" stroke="currentColor" stroke-width="2">
+  <path d="M12 2l3.09 6.26L22 9.27l-5 4.87 1.18 6.88L12 17.77l-6.18 3.25L7 14.14 2 9.27l6.91-1.01L12 2z"/>
+</svg>
+```
+
+**Visibility rules:**
+- Unstarred items: star appears on row `:hover` only
+- Starred items: filled star always visible
+- Star button: `opacity: 0` → `opacity: 1` on hover transition (0.15s)
+
+## Navigation Paths
+
+| Item type | Click navigates to | Route exists? |
+|-----------|-------------------|---------------|
+| App (in Applications tree) | `/apps/{id}` | New stub page |
+| Route | `/routes/{id}` | Existing |
+| App (in Agents tree) | `/apps/{id}` | Same stub page |
+| Agent | `/agents/{id}` | New — currently only `/agents` (list) exists |
+| Dashboards | `/` | Existing (Dashboard) |
+| Admin | `/admin` | New stub page |
+| API Docs | `/api-docs` | New stub page |
+
+### Stub pages needed
+
+Minimal placeholder pages using the design system's `EmptyState` component:
+
+- **AppDetail** (`src/pages/AppDetail/AppDetail.tsx`) — route `/apps/:id`, shows app name from URL param + EmptyState "App detail coming soon"
+- **AgentDetail** (`src/pages/AgentDetail/AgentDetail.tsx`) — route `/agents/:id`, shows agent name + EmptyState
+- **Admin** (`src/pages/Admin/Admin.tsx`) — route `/admin`, EmptyState "Admin panel coming soon"
+- **ApiDocs** (`src/pages/ApiDocs/ApiDocs.tsx`) — route `/api-docs`, EmptyState "API documentation coming soon"
+
+All stub pages use `<AppShell>` with `<Sidebar>` to demonstrate the full navigation flow.
+
+## Search Behavior
+
+- Case-insensitive substring match on node labels
+- When a child matches, its parent node is shown and auto-expanded
+- When no matches, show "No results" text in the navigation area
+- Search clears when input is emptied
+- On clear, restore previous expand/collapse state
+- Search filters both the Applications and Agents trees simultaneously
+
+## Mock Data
+
+### New file: `src/mocks/sidebar.ts`
+
+Exports `SIDEBAR_APPS: SidebarApp[]` — consolidates the duplicated APPS, SIDEBAR_ROUTES, and agents data currently scattered across 6 page files. Each app contains its routes and agents nested inside.
+
+All consumer pages + Inventory demo will import from this single source.
+
+## Files to Create
+
+| File | Purpose |
+|------|---------|
+| `src/design-system/layout/Sidebar/SidebarTree.tsx` | Tree component with health dots, badges, star toggle |
+| `src/design-system/layout/Sidebar/useStarred.ts` | localStorage hook for starred item IDs |
+| `src/mocks/sidebar.ts` | Shared hierarchical sidebar mock data |
+| `src/pages/AppDetail/AppDetail.tsx` | Stub page for `/apps/:id` |
+| `src/pages/AgentDetail/AgentDetail.tsx` | Stub page for `/agents/:id` |
+| `src/pages/Admin/Admin.tsx` | Stub page for `/admin` |
+| `src/pages/ApiDocs/ApiDocs.tsx` | Stub page for `/api-docs` |
+| `src/design-system/layout/Sidebar/Sidebar.test.tsx` | Tests for Sidebar |
+| `src/design-system/layout/Sidebar/useStarred.test.ts` | Tests for useStarred hook |
+
+## Files to Modify
+
+| File | Changes |
+|------|---------|
+| `src/design-system/layout/Sidebar/Sidebar.tsx` | Rewrite: new props, SidebarTree, starred section, bottom links |
+| `src/design-system/layout/Sidebar/Sidebar.module.css` | Add tree styles, starred section, star button, bottom links, SidebarTree styles |
+| `src/design-system/layout/index.ts` | Export new types (SidebarApp, SidebarRoute, SidebarAgent) |
+| `src/App.tsx` | Add routes: `/apps/:id`, `/agents/:id`, `/admin`, `/api-docs` |
+| `src/pages/Dashboard/Dashboard.tsx` | Simplify to `<Sidebar apps={SIDEBAR_APPS} />` |
+| `src/pages/RouteDetail/RouteDetail.tsx` | Same simplification |
+| `src/pages/ExchangeDetail/ExchangeDetail.tsx` | Same simplification |
+| `src/pages/AgentHealth/AgentHealth.tsx` | Same simplification |
+| `src/pages/Metrics/Metrics.tsx` | Same simplification |
+| `src/pages/Inventory/sections/LayoutSection.tsx` | Update demo data to hierarchical shape |
+| `src/mocks/agents.ts` | Make AgentHealth self-contained (no longer extends Sidebar's Agent) |
+| `COMPONENT_GUIDE.md` | Update Sidebar and navigation descriptions |
+
+## Implementation Order
+
+1. **Mock data** (`src/mocks/sidebar.ts`) — needed for development and testing
+2. **Agent type fix** (`src/mocks/agents.ts`) — make AgentHealth self-contained
+3. **useStarred hook** + tests — standalone, no dependencies
+4. **SidebarTree component** — depends on useStarred interface
+5. **Sidebar rewrite** + CSS — composes SidebarTree + useStarred
+6. **Stub pages** — AppDetail, AgentDetail, Admin, ApiDocs
+7. **App.tsx routes** — register new routes
+8. **Consumer migration** — update all 6 pages to use `<Sidebar apps={SIDEBAR_APPS} />`
+9. **Inventory update** — update LayoutSection demo data
+10. **Type exports** — update layout barrel export
+11. **Sidebar tests** — integration tests for Sidebar component
+12. **Docs** — update COMPONENT_GUIDE.md
+
+## Verification
+
+1. `npx tsc --noEmit` — zero TypeScript errors
+2. `npx vitest run` — all tests pass (existing + new)
+3. `npm run build` — clean Vite build
+4. Manual: open `/inventory` → Layout section → verify Sidebar demo renders correctly
+5. Manual: open `/` → verify sidebar trees expand/collapse, starring persists across refresh, search filters both trees, navigation to all routes works
+6. Manual: verify starred section hides when empty, shows grouped items when populated
+7. Manual: verify dark theme rendering (sidebar uses `--sidebar-*` tokens)
+8. `grep -r "onItemClick\|routes={.*SIDEBAR\|agents={.*agents" src/design-system/layout/Sidebar/` — zero hits (old API removed)
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -5,6 +5,10 @@ import { RouteDetail } from './pages/RouteDetail/RouteDetail'
 import { ExchangeDetail } from './pages/ExchangeDetail/ExchangeDetail'
 import { AgentHealth } from './pages/AgentHealth/AgentHealth'
 import { Inventory } from './pages/Inventory/Inventory'
+import { AppDetail } from './pages/AppDetail/AppDetail'
+import { AgentDetail } from './pages/AgentDetail/AgentDetail'
+import { Admin } from './pages/Admin/Admin'
+import { ApiDocs } from './pages/ApiDocs/ApiDocs'

 export default function App() {
  return (
@@ -14,6 +18,10 @@ export default function App() {
      <Route path="/routes/:id" element={<RouteDetail />} />
      <Route path="/exchanges/:id" element={<ExchangeDetail />} />
      <Route path="/agents" element={<AgentHealth />} />
+      <Route path="/agents/:id" element={<AgentDetail />} />
+      <Route path="/apps/:id" element={<AppDetail />} />
+      <Route path="/admin" element={<Admin />} />
+      <Route path="/api-docs" element={<ApiDocs />} />
      <Route path="/inventory" element={<Inventory />} />
    </Routes>
  )
--- a/src/design-system/layout/Sidebar/Sidebar.module.css
+++ b/src/design-system/layout/Sidebar/Sidebar.module.css
@@ -1,5 +1,5 @@
 .sidebar {
-  width: 220px;
+  width: 260px;
  flex-shrink: 0;
  background: var(--sidebar-bg);
  display: flex;
@@ -102,7 +102,7 @@
  padding: 0 6px;
 }

-/* Nav item */
+/* Nav item (flat links like Dashboards) */
 .item {
  display: flex;
  align-items: center;
@@ -129,16 +129,6 @@
  border-left-color: var(--amber);
 }

-.item.active .itemCount {
-  background: rgba(198, 130, 14, 0.2);
-  color: var(--amber-light);
-}
-
-/* Indented route items */
-.indented {
-  padding-left: 22px;
-}
-
 .navIcon {
  font-size: 14px;
  width: 18px;
@@ -154,6 +144,7 @@
 .routeArrow {
  color: var(--sidebar-muted);
  font-size: 10px;
+  flex-shrink: 0;
 }

 /* Item sub-elements */
@@ -169,143 +160,278 @@
  text-overflow: ellipsis;
 }

-.itemMeta {
-  font-size: 11px;
+/* No results */
+.noResults {
+  padding: 16px 18px;
+  font-size: 12px;
  color: var(--sidebar-muted);
-  font-family: var(--font-mono);
+  text-align: center;
 }

-.itemCount {
-  font-family: var(--font-mono);
-  font-size: 11px;
-  color: var(--sidebar-muted);
-  background: rgba(255, 255, 255, 0.06);
-  padding: 1px 6px;
-  border-radius: 10px;
-  flex-shrink: 0;
+/* ── SidebarTree styles ──────────────────────────────────────────────────── */
+
+.treeSection {
+  padding: 0 6px;
+  margin-bottom: 4px;
 }

-/* Health dots */
-.healthDot {
-  width: 7px;
-  height: 7px;
-  border-radius: 50%;
-  flex-shrink: 0;
-}
-
-.healthLive {
-  background: #5db866;
-  box-shadow: 0 0 6px rgba(93, 184, 102, 0.4);
-}
-
-.healthStale {
-  background: var(--warning);
-}
-
-.healthDead {
-  background: var(--sidebar-muted);
-}
-
-/* Divider */
-.divider {
-  height: 1px;
-  background: rgba(255, 255, 255, 0.06);
-  margin: 6px 12px;
-}
-
-/* Agents header */
-.agentsHeader {
-  padding: 14px 12px 6px;
+.treeSectionLabel {
+  padding: 10px 12px 4px;
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
-  letter-spacing: 1.2px;
+  letter-spacing: 1px;
  color: var(--sidebar-muted);
-  display: flex;
-  align-items: center;
-  justify-content: space-between;
-  flex-shrink: 0;
 }

-.agentBadge {
-  font-family: var(--font-mono);
+/* Collapsible section toggle */
+.treeSectionToggle {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  width: 100%;
+  padding: 8px 12px 4px;
  font-size: 10px;
-  padding: 1px 6px;
-  border-radius: 10px;
-  background: rgba(93, 184, 102, 0.15);
-  color: #5db866;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 1px;
+  color: var(--sidebar-muted);
+  background: none;
+  border: none;
+  cursor: pointer;
+  text-align: left;
+  transition: color 0.12s;
 }

-/* Agents list */
-.agentsList {
-  padding: 0 0 6px;
-  overflow-y: auto;
-  max-height: 180px;
-  flex-shrink: 0;
+.treeSectionToggle:hover {
+  color: var(--sidebar-text);
 }

-.agentItem {
+.treeSectionChevron {
+  font-size: 9px;
+  width: 10px;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+}
+
+.tree {
+  list-style: none;
+  margin: 0;
+  padding: 0;
+}
+
+.treeGroup {
+  list-style: none;
+  margin: 0;
+  padding: 0;
+}
+
+.treeRow {
  display: flex;
  align-items: center;
-  gap: 8px;
-  padding: 6px 12px;
-  margin: 0 6px 2px;
+  gap: 6px;
+  padding: 5px 8px;
  border-radius: var(--radius-sm);
-  font-size: 11px;
  color: var(--sidebar-text);
-  transition: background 0.1s;
+  font-size: 12px;
+  cursor: pointer;
+  transition: background 0.12s;
+  border-left: 3px solid transparent;
+  margin-bottom: 1px;
+  user-select: none;
+  position: relative;
 }

-.agentItem:hover {
+.treeRow:hover {
  background: var(--sidebar-hover);
 }

-.agentDot {
-  width: 6px;
-  height: 6px;
-  border-radius: 50%;
-  flex-shrink: 0;
+.treeRowActive {
+  background: var(--sidebar-active);
+  color: var(--amber-light);
+  border-left-color: var(--amber);
 }

-.agentInfo {
+.treeRowActive .treeBadge {
+  background: rgba(198, 130, 14, 0.2);
+  color: var(--amber-light);
+}
+
+/* Chevron */
+.treeChevronSlot {
+  width: 14px;
+  flex-shrink: 0;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+}
+
+.treeChevron {
+  background: none;
+  border: none;
+  padding: 0;
+  margin: 0;
+  color: var(--sidebar-muted);
+  font-size: 11px;
+  cursor: pointer;
+  line-height: 1;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+}
+
+.treeChevron:hover {
+  color: var(--sidebar-text);
+}
+
+/* Icon slot */
+.treeIcon {
+  flex-shrink: 0;
+  display: flex;
+  align-items: center;
+}
+
+/* Label */
+.treeLabel {
  flex: 1;
  min-width: 0;
-}
-
-.agentName {
-  font-family: var(--font-mono);
-  font-size: 11px;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
 }

-.agentDetail {
-  font-size: 10px;
-  color: var(--sidebar-muted);
-}
-
-.agentStats {
-  text-align: right;
+/* Badge */
+.treeBadge {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--sidebar-muted);
+  background: rgba(255, 255, 255, 0.06);
+  padding: 1px 6px;
+  border-radius: 10px;
+  flex-shrink: 0;
+  white-space: nowrap;
 }

-.agentTps {
-  color: var(--sidebar-text);
-}
-
-.agentLastSeen {
+/* Star button */
+.treeStar {
+  background: none;
+  border: none;
+  padding: 0;
+  margin: 0;
  color: var(--sidebar-muted);
+  cursor: pointer;
+  opacity: 0;
+  transition: opacity 0.15s, color 0.15s;
+  display: flex;
+  align-items: center;
+  flex-shrink: 0;
 }

-.agentError {
+.treeStarActive {
+  opacity: 1;
+  color: var(--amber);
+}
+
+.treeRow:hover .treeStar {
+  opacity: 1;
+}
+
+.treeStar:hover {
+  color: var(--amber-light);
+}
+
+/* ── Starred section ─────────────────────────────────────────────────────── */
+
+.starredSection {
+  border-top: 1px solid rgba(255, 255, 255, 0.06);
+  margin-top: 4px;
+}
+
+.starredHeader {
+  color: var(--amber);
+}
+
+.starredList {
+  padding: 0 6px 6px;
+}
+
+.starredGroup {
+  margin-bottom: 4px;
+}
+
+.starredGroupLabel {
+  padding: 4px 12px 2px;
+  font-size: 10px;
+  color: var(--sidebar-muted);
+  font-weight: 500;
+}
+
+.starredItem {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+  padding: 4px 12px;
+  border-radius: var(--radius-sm);
+  color: var(--sidebar-text);
+  font-size: 12px;
+  cursor: pointer;
+  transition: background 0.12s;
+  user-select: none;
+}
+
+.starredItem:hover {
+  background: var(--sidebar-hover);
+}
+
+.starredItemInfo {
+  flex: 1;
+  min-width: 0;
+  display: flex;
+  flex-direction: column;
+}
+
+.starredItemName {
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  font-weight: 500;
+}
+
+.starredItemContext {
+  font-size: 10px;
+  color: var(--sidebar-muted);
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+}
+
+/* Remove button */
+.starredRemove {
+  background: none;
+  border: none;
+  padding: 2px;
+  margin: 0;
+  color: var(--sidebar-muted);
+  cursor: pointer;
+  opacity: 0;
+  transition: opacity 0.15s, color 0.15s;
+  display: flex;
+  align-items: center;
+  flex-shrink: 0;
+}
+
+.starredItem:hover .starredRemove {
+  opacity: 1;
+}
+
+.starredRemove:hover {
  color: var(--error);
 }

-/* Bottom links */
+/* ── Bottom links ────────────────────────────────────────────────────────── */
+
 .bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  padding: 6px;
@@ -331,6 +457,12 @@
  color: var(--sidebar-text);
 }

+.bottomItemActive {
+  background: var(--sidebar-active);
+  color: var(--amber-light);
+  border-left-color: var(--amber);
+}
+
 .bottomIcon {
  font-size: 13px;
  width: 18px;
--- a/src/design-system/layout/Sidebar/Sidebar.test.tsx
+++ b/src/design-system/layout/Sidebar/Sidebar.test.tsx
@@ -0,0 +1,172 @@
+import { describe, it, expect, beforeEach } from 'vitest'
+import { render, screen } from '@testing-library/react'
+import userEvent from '@testing-library/user-event'
+import { MemoryRouter } from 'react-router-dom'
+import { Sidebar, type SidebarApp } from './Sidebar'
+import { ThemeProvider } from '../../providers/ThemeProvider'
+
+const TEST_APPS: SidebarApp[] = [
+  {
+    id: 'order-service',
+    name: 'order-service',
+    health: 'live',
+    exchangeCount: 1433,
+    routes: [
+      { id: 'order-intake', name: 'order-intake', exchangeCount: 892 },
+      { id: 'order-enrichment', name: 'order-enrichment', exchangeCount: 541 },
+    ],
+    agents: [
+      { id: 'prod-1', name: 'prod-1', status: 'live', tps: '14.2/s' },
+      { id: 'prod-2', name: 'prod-2', status: 'live', tps: '11.8/s' },
+    ],
+  },
+  {
+    id: 'payment-svc',
+    name: 'payment-svc',
+    health: 'live',
+    exchangeCount: 912,
+    routes: [
+      { id: 'payment-process', name: 'payment-process', exchangeCount: 414 },
+    ],
+    agents: [],
+  },
+]
+
+function renderSidebar(props: Partial<Parameters<typeof Sidebar>[0]> = {}) {
+  return render(
+    <ThemeProvider>
+      <MemoryRouter>
+        <Sidebar apps={TEST_APPS} {...props} />
+      </MemoryRouter>
+    </ThemeProvider>,
+  )
+}
+
+describe('Sidebar', () => {
+  beforeEach(() => {
+    localStorage.clear()
+    sessionStorage.clear()
+  })
+
+  it('renders the logo and brand name', () => {
+    renderSidebar()
+    expect(screen.getByText('cameleer')).toBeInTheDocument()
+    expect(screen.getByText('v3.2.1')).toBeInTheDocument()
+  })
+
+  it('renders the search input', () => {
+    renderSidebar()
+    expect(screen.getByPlaceholderText('Filter...')).toBeInTheDocument()
+  })
+
+  it('renders Navigation section header', () => {
+    renderSidebar()
+    expect(screen.getByText('Navigation')).toBeInTheDocument()
+  })
+
+  it('renders Applications tree section', () => {
+    renderSidebar()
+    expect(screen.getByText('Applications')).toBeInTheDocument()
+  })
+
+  it('renders Agents tree section', () => {
+    renderSidebar()
+    expect(screen.getByText('Agents')).toBeInTheDocument()
+  })
+
+  it('renders Dashboards nav link', () => {
+    renderSidebar()
+    expect(screen.getByText('Dashboards')).toBeInTheDocument()
+  })
+
+  it('renders bottom links', () => {
+    renderSidebar()
+    expect(screen.getByText('Admin')).toBeInTheDocument()
+    expect(screen.getByText('API Docs')).toBeInTheDocument()
+  })
+
+  it('renders app names in the Applications tree', () => {
+    renderSidebar()
+    // order-service appears in both Applications and Agents trees
+    expect(screen.getAllByText('order-service').length).toBeGreaterThanOrEqual(1)
+    expect(screen.getByText('payment-svc')).toBeInTheDocument()
+  })
+
+  it('renders exchange count badges', () => {
+    renderSidebar()
+    expect(screen.getByText('1.4k')).toBeInTheDocument()
+  })
+
+  it('renders agent live count badge in Agents tree', () => {
+    renderSidebar()
+    expect(screen.getByText('2/2 live')).toBeInTheDocument()
+  })
+
+  it('does not show starred section when nothing is starred', () => {
+    renderSidebar()
+    expect(screen.queryByText('★ Starred')).not.toBeInTheDocument()
+  })
+
+  it('shows starred section after starring an item', async () => {
+    const user = userEvent.setup()
+    renderSidebar()
+
+    // Find the first app row (order-service in Applications tree) and hover to reveal star
+    const appRows = screen.getAllByText('order-service')
+    const appRow = appRows[0].closest('[role="treeitem"]')!
+    await user.hover(appRow)
+
+    // Click the star button
+    const starBtn = appRow.querySelector('button[aria-label="Add to starred"]')!
+    await user.click(starBtn)
+
+    expect(screen.getByText('★ Starred')).toBeInTheDocument()
+  })
+
+  it('filters tree items by search', async () => {
+    const user = userEvent.setup()
+    renderSidebar()
+
+    const searchInput = screen.getByPlaceholderText('Filter...')
+    await user.type(searchInput, 'payment')
+
+    // payment-svc should still be visible
+    expect(screen.getByText('payment-svc')).toBeInTheDocument()
+  })
+
+  it('expands tree to show children when chevron is clicked', async () => {
+    const user = userEvent.setup()
+    renderSidebar()
+
+    // Find the expand button for order-service in Applications tree
+    const expandBtns = screen.getAllByLabelText('Expand')
+    await user.click(expandBtns[0])
+
+    // Routes should now be visible
+    expect(screen.getByText('order-intake')).toBeInTheDocument()
+    expect(screen.getByText('order-enrichment')).toBeInTheDocument()
+  })
+
+  it('collapses expanded tree when chevron is clicked again', async () => {
+    const user = userEvent.setup()
+    renderSidebar()
+
+    const expandBtns = screen.getAllByLabelText('Expand')
+    await user.click(expandBtns[0])
+    expect(screen.getByText('order-intake')).toBeInTheDocument()
+
+    const collapseBtn = screen.getByLabelText('Collapse')
+    await user.click(collapseBtn)
+    expect(screen.queryByText('order-intake')).not.toBeInTheDocument()
+  })
+
+  it('does not render apps with no agents in the Agents tree', () => {
+    renderSidebar()
+    // payment-svc has no agents, so it shouldn't appear under the Agents section header
+    // But it still appears under Applications. Let's check the agent tree specifically.
+    const agentBadges = screen.queryAllByText(/\/.*live/)
+    // Only order-service should have an agent badge
+    expect(agentBadges).toHaveLength(1)
+    expect(agentBadges[0].textContent).toBe('2/2 live')
+  })
+})
--- a/src/design-system/layout/Sidebar/Sidebar.tsx
+++ b/src/design-system/layout/Sidebar/Sidebar.tsx
@@ -1,89 +1,222 @@
-import { useState } from 'react'
+import { useState, useMemo } from 'react'
 import { useNavigate, useLocation } from 'react-router-dom'
 import styles from './Sidebar.module.css'
 import camelLogoUrl from '../../../assets/camel-logo.svg'
+import { SidebarTree, type SidebarTreeNode } from './SidebarTree'
+import { useStarred } from './useStarred'
+import { StatusDot } from '../../primitives/StatusDot/StatusDot'

-export interface App {
+// ── Types ────────────────────────────────────────────────────────────────────
+
+export interface SidebarApp {
  id: string
  name: string
-  agentCount: number
  health: 'live' | 'stale' | 'dead'
  exchangeCount: number
+  routes: SidebarRoute[]
+  agents: SidebarAgent[]
 }

-export interface Route {
+export interface SidebarRoute {
  id: string
  name: string
  exchangeCount: number
 }

-export interface Agent {
+export interface SidebarAgent {
  id: string
  name: string
-  service: string
-  version: string
-  tps: string
-  lastSeen: string
  status: 'live' | 'stale' | 'dead'
-  errorRate?: string
+  tps: string
 }

 interface SidebarProps {
-  apps: App[]
-  routes: Route[]
-  agents: Agent[]
-  activeItem?: string
-  onItemClick?: (id: string) => void
+  apps: SidebarApp[]
+  className?: string
 }

-function HealthDot({ status }: { status: 'live' | 'stale' | 'dead' }) {
+// ── Helpers ──────────────────────────────────────────────────────────────────
+
+function formatCount(n: number): string {
+  if (n >= 1000) return `${(n / 1000).toFixed(1)}k`
+  return String(n)
+}
+
+function buildAppTreeNodes(apps: SidebarApp[]): SidebarTreeNode[] {
+  return apps.map((app) => ({
+    id: `app:${app.id}`,
+    label: app.name,
+    icon: <StatusDot variant={app.health} />,
+    badge: formatCount(app.exchangeCount),
+    path: `/apps/${app.id}`,
+    starrable: true,
+    starKey: app.id,
+    children: app.routes.map((route) => ({
+      id: `route:${app.id}:${route.id}`,
+      starKey: `${app.id}:${route.id}`,
+      label: route.name,
+      icon: <span className={styles.routeArrow}>&#9656;</span>,
+      badge: formatCount(route.exchangeCount),
+      path: `/routes/${route.id}`,
+      starrable: true,
+    })),
+  }))
+}
+
+function buildAgentTreeNodes(apps: SidebarApp[]): SidebarTreeNode[] {
+  return apps
+    .filter((app) => app.agents.length > 0)
+    .map((app) => {
+      const liveCount = app.agents.filter((a) => a.status === 'live').length
+      return {
+        id: `agents:${app.id}`,
+        label: app.name,
+        icon: <StatusDot variant={app.health} />,
+        badge: `${liveCount}/${app.agents.length} live`,
+        path: `/agents/${app.id}`,
+        starrable: true,
+        starKey: `agents:${app.id}`,
+        children: app.agents.map((agent) => ({
+          id: `agent:${app.id}:${agent.id}`,
+          starKey: `${app.id}:${agent.id}`,
+          label: agent.name,
+          badge: agent.tps,
+          path: `/agents/${agent.id}`,
+          starrable: true,
+        })),
+      }
+    })
+}
+
+// ── Starred section helpers ──────────────────────────────────────────────────
+
+interface StarredItem {
+  starKey: string
+  label: string
+  icon?: React.ReactNode
+  path: string
+  type: 'application' | 'route' | 'agent'
+  parentApp?: string
+}
+
+function collectStarredItems(apps: SidebarApp[], starredIds: Set<string>): StarredItem[] {
+  const items: StarredItem[] = []
+
+  for (const app of apps) {
+    if (starredIds.has(app.id)) {
+      items.push({
+        starKey: app.id,
+        label: app.name,
+        icon: <StatusDot variant={app.health} />,
+        path: `/apps/${app.id}`,
+        type: 'application',
+      })
+    }
+    for (const route of app.routes) {
+      const key = `${app.id}:${route.id}`
+      if (starredIds.has(key)) {
+        items.push({
+          starKey: key,
+          label: route.name,
+          path: `/routes/${route.id}`,
+          type: 'route',
+          parentApp: app.name,
+        })
+      }
+    }
+    for (const agent of app.agents) {
+      const key = `${app.id}:${agent.id}`
+      if (starredIds.has(key)) {
+        items.push({
+          starKey: key,
+          label: agent.name,
+          path: `/agents/${agent.id}`,
+          type: 'agent',
+          parentApp: app.name,
+        })
+      }
+    }
+  }
+
+  return items
+}
+
+// ── StarredGroup ─────────────────────────────────────────────────────────────
+
+function StarredGroup({
+  label,
+  items,
+  onNavigate,
+  onRemove,
+}: {
+  label: string
+  items: StarredItem[]
+  onNavigate: (path: string) => void
+  onRemove: (starKey: string) => void
+}) {
  return (
-    <span
-      className={[
-        styles.healthDot,
-        status === 'live' ? styles.healthLive : '',
-        status === 'stale' ? styles.healthStale : '',
-        status === 'dead' ? styles.healthDead : '',
-      ]
-        .filter(Boolean)
-        .join(' ')}
-    />
+    <div className={styles.starredGroup}>
+      <div className={styles.starredGroupLabel}>{label}</div>
+      {items.map((item) => (
+        <div
+          key={item.starKey}
+          className={styles.starredItem}
+          onClick={() => onNavigate(item.path)}
+          role="button"
+          tabIndex={0}
+          onKeyDown={(e) => { if (e.key === 'Enter' || e.key === ' ') onNavigate(item.path) }}
+        >
+          {item.icon}
+          <div className={styles.starredItemInfo}>
+            <span className={styles.starredItemName}>{item.label}</span>
+            {item.parentApp && (
+              <span className={styles.starredItemContext}>{item.parentApp}</span>
+            )}
+          </div>
+          <button
+            className={styles.starredRemove}
+            onClick={(e) => { e.stopPropagation(); onRemove(item.starKey) }}
+            tabIndex={-1}
+            aria-label={`Remove ${item.label} from starred`}
+          >
+            <svg width="12" height="12" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+              <line x1="18" y1="6" x2="6" y2="18" />
+              <line x1="6" y1="6" x2="18" y2="18" />
+            </svg>
+          </button>
+        </div>
+      ))}
+    </div>
  )
 }

-interface NavItem {
-  id: string
-  label: string
-  path: string
-  icon: string
-}
+// ── Sidebar ──────────────────────────────────────────────────────────────────

-const NAV_ITEMS: NavItem[] = [
-  { id: 'dashboard', label: 'Dashboard', path: '/', icon: '▦' },
-  { id: 'metrics', label: 'Metrics', path: '/metrics', icon: '◔' },
-  { id: 'agents', label: 'Agents', path: '/agents', icon: '⬡' },
-]
-
-export function Sidebar({
-  apps,
-  routes,
-  agents,
-  activeItem,
-  onItemClick,
-}: SidebarProps) {
+export function Sidebar({ apps, className }: SidebarProps) {
  const [search, setSearch] = useState('')
+  const [appsCollapsed, setAppsCollapsed] = useState(false)
+  const [agentsCollapsed, setAgentsCollapsed] = useState(false)
  const navigate = useNavigate()
  const location = useLocation()
+  const { starredIds, isStarred, toggleStar } = useStarred()

-  const liveCount = agents.filter((a) => a.status === 'live').length
-  const agentBadge = `${liveCount}/${agents.length} live`
+  // Build tree data
+  const appNodes = useMemo(() => buildAppTreeNodes(apps), [apps])
+  const agentNodes = useMemo(() => buildAgentTreeNodes(apps), [apps])

-  const filteredApps = search
-    ? apps.filter((a) => a.name.toLowerCase().includes(search.toLowerCase()))
-    : apps
+  // Build starred items
+  const starredItems = useMemo(
+    () => collectStarredItems(apps, starredIds),
+    [apps, starredIds],
+  )
+
+  const starredApps = starredItems.filter((i) => i.type === 'application')
+  const starredRoutes = starredItems.filter((i) => i.type === 'route')
+  const starredAgents = starredItems.filter((i) => i.type === 'agent')
+  const hasStarred = starredItems.length > 0

  return (
-    <aside className={styles.sidebar}>
+    <aside className={`${styles.sidebar} ${className ?? ''}`}>
      {/* Logo */}
      <div className={styles.logo} onClick={() => navigate('/')} style={{ cursor: 'pointer' }}>
        <img src={camelLogoUrl} alt="" aria-hidden="true" className={styles.logoImg} />
@@ -105,145 +238,148 @@ export function Sidebar({
          <input
            className={styles.searchInput}
            type="text"
-            placeholder="Filter apps..."
+            placeholder="Filter..."
            value={search}
            onChange={(e) => setSearch(e.target.value)}
          />
        </div>
      </div>

-      {/* Scrollable nav area */}
+      {/* Navigation (scrollable) — includes starred section */}
      <div className={styles.navArea}>
-        {/* Top-level navigation */}
        <div className={styles.section}>Navigation</div>
-        <div className={styles.items}>
-          {NAV_ITEMS.map((nav) => (
-            <div
-              key={nav.id}
-              className={[
-                styles.item,
-                location.pathname === nav.path ? styles.active : '',
-              ].filter(Boolean).join(' ')}
-              onClick={() => navigate(nav.path)}
-              role="button"
-              tabIndex={0}
-              onKeyDown={(e) => { if (e.key === 'Enter' || e.key === ' ') navigate(nav.path) }}
-            >
-              <span className={styles.navIcon}>{nav.icon}</span>
-              <div className={styles.itemInfo}>
-                <div className={styles.itemName}>{nav.label}</div>
-              </div>
-            </div>
-          ))}
-        </div>

-        <div className={styles.divider} />
-
-        {/* Applications section */}
-        <div className={styles.section}>Applications</div>
-        <div className={styles.items}>
-          {filteredApps.map((app) => (
-            <div
-              key={app.id}
-              className={[
-                styles.item,
-                activeItem === app.id ? styles.active : '',
-              ]
-                .filter(Boolean)
-                .join(' ')}
-              onClick={() => onItemClick?.(app.id)}
-              role="button"
-              tabIndex={0}
-              onKeyDown={(e) => {
-                if (e.key === 'Enter' || e.key === ' ') onItemClick?.(app.id)
-              }}
-            >
-              <HealthDot status={app.health} />
-              <div className={styles.itemInfo}>
-                <div className={styles.itemName}>{app.name}</div>
-                <div className={styles.itemMeta}>{app.agentCount} agent{app.agentCount !== 1 ? 's' : ''}</div>
-              </div>
-              <span className={styles.itemCount}>{app.exchangeCount.toLocaleString()}</span>
-            </div>
-          ))}
-        </div>
-
-        {/* Divider */}
-        <div className={styles.divider} />
-
-        {/* Routes section */}
-        <div className={styles.section}>Routes</div>
-        <div className={styles.items}>
-          {routes.map((route) => (
-            <div
-              key={route.id}
-              className={[
-                styles.item,
-                styles.indented,
-                activeItem === route.id || location.pathname === `/routes/${route.id}` ? styles.active : '',
-              ]
-                .filter(Boolean)
-                .join(' ')}
-              onClick={() => { onItemClick?.(route.id); navigate(`/routes/${route.id}`) }}
-              role="button"
-              tabIndex={0}
-              onKeyDown={(e) => {
-                if (e.key === 'Enter' || e.key === ' ') { onItemClick?.(route.id); navigate(`/routes/${route.id}`) }
-              }}
-            >
-              <span className={styles.routeArrow}>&#9656;</span>
-              <div className={styles.itemInfo}>
-                <div className={styles.itemName}>{route.name}</div>
-              </div>
-              <span className={styles.itemCount}>{route.exchangeCount.toLocaleString()}</span>
-            </div>
-          ))}
-        </div>
-      </div>
-
-      {/* Agent health section */}
-      <div className={styles.agentsHeader}>
-        <span>Agents</span>
-        <span className={styles.agentBadge}>{agentBadge}</span>
-      </div>
-      <div className={styles.agentsList}>
-        {agents.map((agent) => (
-          <div key={agent.id} className={styles.agentItem}>
-            <span
-              className={[
-                styles.agentDot,
-                agent.status === 'live' ? styles.healthLive : '',
-                agent.status === 'stale' ? styles.healthStale : '',
-                agent.status === 'dead' ? styles.healthDead : '',
-              ]
-                .filter(Boolean)
-                .join(' ')}
+        {/* Applications tree (collapsible) */}
+        <div className={styles.treeSection}>
+          <button
+            className={styles.treeSectionToggle}
+            onClick={() => setAppsCollapsed((v) => !v)}
+            aria-expanded={!appsCollapsed}
+          >
+            <span className={styles.treeSectionChevron}>{appsCollapsed ? '▸' : '▾'}</span>
+            <span>Applications</span>
+          </button>
+          {!appsCollapsed && (
+            <SidebarTree
+              nodes={appNodes}
+              selectedPath={location.pathname}
+              isStarred={isStarred}
+              onToggleStar={toggleStar}
+              filterQuery={search}
+              persistKey="cameleer:expanded:apps"
            />
-            <div className={styles.agentInfo}>
-              <div className={styles.agentName}>{agent.name}</div>
-              <div className={styles.agentDetail}>{agent.service} {agent.version}</div>
-            </div>
-            <div className={styles.agentStats}>
-              <div className={styles.agentTps}>{agent.tps}</div>
-              <div
-                className={agent.errorRate ? styles.agentError : styles.agentLastSeen}
-              >
-                {agent.errorRate ?? agent.lastSeen}
-              </div>
+          )}
+        </div>
+
+        {/* Agents tree (collapsible) */}
+        <div className={styles.treeSection}>
+          <button
+            className={styles.treeSectionToggle}
+            onClick={() => setAgentsCollapsed((v) => !v)}
+            aria-expanded={!agentsCollapsed}
+          >
+            <span className={styles.treeSectionChevron}>{agentsCollapsed ? '▸' : '▾'}</span>
+            <span>Agents</span>
+          </button>
+          {!agentsCollapsed && (
+            <SidebarTree
+              nodes={agentNodes}
+              selectedPath={location.pathname}
+              isStarred={isStarred}
+              onToggleStar={toggleStar}
+              filterQuery={search}
+              persistKey="cameleer:expanded:agents"
+            />
+          )}
+        </div>
+
+        {/* Dashboards flat link */}
+        <div className={styles.items}>
+          <div
+            className={[
+              styles.item,
+              location.pathname === '/' ? styles.active : '',
+            ].filter(Boolean).join(' ')}
+            onClick={() => navigate('/')}
+            role="button"
+            tabIndex={0}
+            onKeyDown={(e) => { if (e.key === 'Enter' || e.key === ' ') navigate('/') }}
+          >
+            <span className={styles.navIcon}>▦</span>
+            <div className={styles.itemInfo}>
+              <div className={styles.itemName}>Dashboards</div>
            </div>
          </div>
-        ))}
+        </div>
+
+        {/* No results message */}
+        {search && appNodes.length === 0 && agentNodes.length === 0 && (
+          <div className={styles.noResults}>No results</div>
+        )}
+
+        {/* Starred section (inside scrollable area, hidden when empty) */}
+        {hasStarred && (
+          <div className={styles.starredSection}>
+            <div className={styles.section}>
+              <span className={styles.starredHeader}>★ Starred</span>
+            </div>
+            <div className={styles.starredList}>
+              {starredApps.length > 0 && (
+                <StarredGroup
+                  label="Applications"
+                  items={starredApps}
+                  onNavigate={navigate}
+                  onRemove={toggleStar}
+                />
+              )}
+              {starredRoutes.length > 0 && (
+                <StarredGroup
+                  label="Routes"
+                  items={starredRoutes}
+                  onNavigate={navigate}
+                  onRemove={toggleStar}
+                />
+              )}
+              {starredAgents.length > 0 && (
+                <StarredGroup
+                  label="Agents"
+                  items={starredAgents}
+                  onNavigate={navigate}
+                  onRemove={toggleStar}
+                />
+              )}
+            </div>
+          </div>
+        )}
      </div>

      {/* Bottom links */}
      <div className={styles.bottom}>
-        <div className={styles.bottomItem}>
+        <div
+          className={[
+            styles.bottomItem,
+            location.pathname === '/admin' ? styles.bottomItemActive : '',
+          ].filter(Boolean).join(' ')}
+          onClick={() => navigate('/admin')}
+          role="button"
+          tabIndex={0}
+          onKeyDown={(e) => { if (e.key === 'Enter' || e.key === ' ') navigate('/admin') }}
+        >
          <span className={styles.bottomIcon}>&#9881;</span>
          <div className={styles.itemInfo}>
            <div className={styles.itemName}>Admin</div>
          </div>
        </div>
-        <div className={styles.bottomItem}>
+        <div
+          className={[
+            styles.bottomItem,
+            location.pathname === '/api-docs' ? styles.bottomItemActive : '',
+          ].filter(Boolean).join(' ')}
+          onClick={() => navigate('/api-docs')}
+          role="button"
+          tabIndex={0}
+          onKeyDown={(e) => { if (e.key === 'Enter' || e.key === ' ') navigate('/api-docs') }}
+        >
          <span className={styles.bottomIcon}>&#9776;</span>
          <div className={styles.itemInfo}>
            <div className={styles.itemName}>API Docs</div>
@@ -253,3 +389,4 @@ export function Sidebar({
    </aside>
  )
 }
+
--- a/src/design-system/layout/Sidebar/SidebarTree.tsx
+++ b/src/design-system/layout/Sidebar/SidebarTree.tsx
@@ -0,0 +1,429 @@
+import {
+  useState,
+  useRef,
+  useCallback,
+  useMemo,
+  type ReactNode,
+  type KeyboardEvent,
+  type MouseEvent,
+} from 'react'
+import { useNavigate } from 'react-router-dom'
+import styles from './Sidebar.module.css'
+
+// ── Types ────────────────────────────────────────────────────────────────────
+
+export interface SidebarTreeNode {
+  id: string
+  label: string
+  icon?: ReactNode
+  badge?: string
+  path?: string
+  starrable?: boolean
+  starKey?: string       // unique key for starring (defaults to id)
+  children?: SidebarTreeNode[]
+}
+
+export interface SidebarTreeProps {
+  nodes: SidebarTreeNode[]
+  selectedPath?: string   // current URL path — matches against node.path
+  isStarred: (id: string) => boolean
+  onToggleStar: (id: string) => void
+  className?: string
+  filterQuery?: string
+  persistKey?: string     // sessionStorage key to persist expand state across remounts
+}
+
+// ── Star icon SVGs ───────────────────────────────────────────────────────────
+
+function StarOutline() {
+  return (
+    <svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2">
+      <path d="M12 2l3.09 6.26L22 9.27l-5 4.87 1.18 6.88L12 17.77l-6.18 3.25L7 14.14 2 9.27l6.91-1.01L12 2z" />
+    </svg>
+  )
+}
+
+function StarFilled() {
+  return (
+    <svg width="14" height="14" viewBox="0 0 24 24" fill="currentColor" stroke="currentColor" strokeWidth="2">
+      <path d="M12 2l3.09 6.26L22 9.27l-5 4.87 1.18 6.88L12 17.77l-6.18 3.25L7 14.14 2 9.27l6.91-1.01L12 2z" />
+    </svg>
+  )
+}
+
+// ── Persistent expand state ──────────────────────────────────────────────────
+
+function readExpandState(key: string): Set<string> {
+  try {
+    const raw = sessionStorage.getItem(key)
+    if (raw) {
+      const arr = JSON.parse(raw)
+      if (Array.isArray(arr)) return new Set(arr)
+    }
+  } catch { /* ignore */ }
+  return new Set()
+}
+
+function writeExpandState(key: string, ids: Set<string>): void {
+  try {
+    sessionStorage.setItem(key, JSON.stringify([...ids]))
+  } catch { /* ignore */ }
+}
+
+// ── Flat node for keyboard nav ───────────────────────────────────────────────
+
+interface FlatNode {
+  node: SidebarTreeNode
+  depth: number
+  parentId: string | null
+}
+
+function flattenVisible(
+  nodes: SidebarTreeNode[],
+  expandedIds: Set<string>,
+  depth = 0,
+  parentId: string | null = null,
+): FlatNode[] {
+  const result: FlatNode[] = []
+  for (const node of nodes) {
+    result.push({ node, depth, parentId })
+    if (node.children && node.children.length > 0 && expandedIds.has(node.id)) {
+      result.push(...flattenVisible(node.children, expandedIds, depth + 1, node.id))
+    }
+  }
+  return result
+}
+
+// ── Filter logic ─────────────────────────────────────────────────────────────
+
+function filterNodes(
+  nodes: SidebarTreeNode[],
+  query: string,
+): { filtered: SidebarTreeNode[]; matchedParentIds: Set<string> } {
+  if (!query) return { filtered: nodes, matchedParentIds: new Set() }
+  const q = query.toLowerCase()
+  const matchedParentIds = new Set<string>()
+
+  function walk(nodeList: SidebarTreeNode[]): SidebarTreeNode[] {
+    const result: SidebarTreeNode[] = []
+    for (const node of nodeList) {
+      const childResults = node.children ? walk(node.children) : []
+      const selfMatches = node.label.toLowerCase().includes(q)
+
+      if (selfMatches || childResults.length > 0) {
+        if (childResults.length > 0) {
+          matchedParentIds.add(node.id)
+        }
+        result.push({
+          ...node,
+          children: childResults.length > 0
+            ? childResults
+            : node.children?.filter((c) => c.label.toLowerCase().includes(q)),
+        })
+      }
+    }
+    return result
+  }
+
+  return { filtered: walk(nodes), matchedParentIds }
+}
+
+// ── SidebarTree ──────────────────────────────────────────────────────────────
+
+export function SidebarTree({
+  nodes,
+  selectedPath,
+  isStarred,
+  onToggleStar,
+  className,
+  filterQuery,
+  persistKey,
+}: SidebarTreeProps) {
+  const navigate = useNavigate()
+
+  // Expand/collapse state — optionally persisted to sessionStorage
+  const [userExpandedIds, setUserExpandedIds] = useState<Set<string>>(
+    () => persistKey ? readExpandState(persistKey) : new Set(),
+  )
+
+  // Filter
+  const { filtered, matchedParentIds } = useMemo(
+    () => filterNodes(nodes, filterQuery ?? ''),
+    [nodes, filterQuery],
+  )
+
+  // Effective expanded set: user toggles + auto-expanded from search
+  const expandedSet = useMemo(() => {
+    if (filterQuery) {
+      return new Set([...userExpandedIds, ...matchedParentIds])
+    }
+    return userExpandedIds
+  }, [userExpandedIds, matchedParentIds, filterQuery])
+
+  function handleToggle(id: string) {
+    setUserExpandedIds((prev) => {
+      const next = new Set(prev)
+      if (next.has(id)) {
+        next.delete(id)
+      } else {
+        next.add(id)
+      }
+      if (persistKey) writeExpandState(persistKey, next)
+      return next
+    })
+  }
+
+  // Keyboard navigation
+  const [focusedId, setFocusedId] = useState<string | null>(null)
+  const treeRef = useRef<HTMLUListElement>(null)
+
+  const visibleNodes = useMemo(
+    () => flattenVisible(filtered, expandedSet),
+    [filtered, expandedSet],
+  )
+
+  const getFocusedIndex = useCallback(() => {
+    if (focusedId === null) return -1
+    return visibleNodes.findIndex((fn) => fn.node.id === focusedId)
+  }, [focusedId, visibleNodes])
+
+  function focusNode(id: string) {
+    const el = treeRef.current?.querySelector(`[data-nodeid="${CSS.escape(id)}"]`) as HTMLElement | null
+    if (el) {
+      el.focus()
+    } else {
+      setFocusedId(id)
+    }
+  }
+
+  const handleKeyDown = useCallback(
+    (e: KeyboardEvent<HTMLUListElement>) => {
+      const currentIndex = getFocusedIndex()
+      const current = visibleNodes[currentIndex]
+
+      switch (e.key) {
+        case 'ArrowDown': {
+          e.preventDefault()
+          const next = visibleNodes[currentIndex + 1]
+          if (next) focusNode(next.node.id)
+          break
+        }
+        case 'ArrowUp': {
+          e.preventDefault()
+          const prev = visibleNodes[currentIndex - 1]
+          if (prev) focusNode(prev.node.id)
+          break
+        }
+        case 'ArrowRight': {
+          e.preventDefault()
+          if (!current) break
+          const hasChildren = current.node.children && current.node.children.length > 0
+          if (hasChildren) {
+            if (!expandedSet.has(current.node.id)) {
+              handleToggle(current.node.id)
+            } else {
+              const next = visibleNodes[currentIndex + 1]
+              if (next) focusNode(next.node.id)
+            }
+          }
+          break
+        }
+        case 'ArrowLeft': {
+          e.preventDefault()
+          if (!current) break
+          const hasChildren = current.node.children && current.node.children.length > 0
+          if (hasChildren && expandedSet.has(current.node.id)) {
+            handleToggle(current.node.id)
+          } else if (current.parentId !== null) {
+            focusNode(current.parentId)
+          }
+          break
+        }
+        case 'Enter': {
+          e.preventDefault()
+          if (current?.node.path) {
+            navigate(current.node.path)
+          }
+          break
+        }
+        case 'Home': {
+          e.preventDefault()
+          if (visibleNodes.length > 0) {
+            focusNode(visibleNodes[0].node.id)
+          }
+          break
+        }
+        case 'End': {
+          e.preventDefault()
+          if (visibleNodes.length > 0) {
+            focusNode(visibleNodes[visibleNodes.length - 1].node.id)
+          }
+          break
+        }
+      }
+    },
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+    [visibleNodes, expandedSet, focusedId],
+  )
+
+  return (
+    <ul
+      ref={treeRef}
+      role="tree"
+      className={`${styles.tree} ${className ?? ''}`}
+      onKeyDown={handleKeyDown}
+    >
+      {filtered.map((node) => (
+        <SidebarTreeRow
+          key={node.id}
+          node={node}
+          depth={0}
+          expandedSet={expandedSet}
+          selectedPath={selectedPath}
+          focusedId={focusedId}
+          isStarred={isStarred}
+          onToggle={handleToggle}
+          onToggleStar={onToggleStar}
+          onFocus={setFocusedId}
+          navigate={navigate}
+        />
+      ))}
+    </ul>
+  )
+}
+
+// ── Row ──────────────────────────────────────────────────────────────────────
+
+interface SidebarTreeRowProps {
+  node: SidebarTreeNode
+  depth: number
+  expandedSet: Set<string>
+  selectedPath?: string
+  focusedId: string | null
+  isStarred: (id: string) => boolean
+  onToggle: (id: string) => void
+  onToggleStar: (id: string) => void
+  onFocus: (id: string) => void
+  navigate: (path: string) => void
+}
+
+function SidebarTreeRow({
+  node,
+  depth,
+  expandedSet,
+  selectedPath,
+  focusedId,
+  isStarred,
+  onToggle,
+  onToggleStar,
+  onFocus,
+  navigate,
+}: SidebarTreeRowProps) {
+  const hasChildren = node.children && node.children.length > 0
+  const isExpanded = expandedSet.has(node.id)
+  const isSelected = Boolean(node.path && selectedPath === node.path)
+  const isFocused = focusedId === node.id
+  const effectiveStarKey = node.starKey ?? node.id
+  const starred = isStarred(effectiveStarKey)
+
+  function handleRowClick() {
+    if (node.path) {
+      navigate(node.path)
+    }
+  }
+
+  function handleChevronClick(e: MouseEvent) {
+    e.stopPropagation()
+    onToggle(node.id)
+  }
+
+  function handleStarClick(e: MouseEvent) {
+    e.stopPropagation()
+    onToggleStar(effectiveStarKey)
+  }
+
+  const rowClass = [
+    styles.treeRow,
+    isSelected ? styles.treeRowActive : '',
+  ]
+    .filter(Boolean)
+    .join(' ')
+
+  return (
+    <li role="none">
+      <div
+        role="treeitem"
+        aria-expanded={hasChildren ? isExpanded : undefined}
+        aria-selected={isSelected}
+        tabIndex={isFocused ? 0 : -1}
+        data-nodeid={node.id}
+        className={rowClass}
+        style={{ paddingLeft: `${depth * 16 + 8}px` }}
+        onClick={handleRowClick}
+        onFocus={() => onFocus(node.id)}
+      >
+        {/* Chevron */}
+        <span className={styles.treeChevronSlot}>
+          {hasChildren ? (
+            <button
+              className={styles.treeChevron}
+              onClick={handleChevronClick}
+              tabIndex={-1}
+              aria-label={isExpanded ? 'Collapse' : 'Expand'}
+            >
+              {isExpanded ? '▾' : '▸'}
+            </button>
+          ) : null}
+        </span>
+
+        {/* Icon (health dot, arrow, etc.) */}
+        {node.icon && (
+          <span className={styles.treeIcon} aria-hidden="true">
+            {node.icon}
+          </span>
+        )}
+
+        {/* Label */}
+        <span className={styles.treeLabel}>{node.label}</span>
+
+        {/* Badge */}
+        {node.badge && (
+          <span className={styles.treeBadge}>{node.badge}</span>
+        )}
+
+        {/* Star */}
+        {node.starrable && (
+          <button
+            className={`${styles.treeStar} ${starred ? styles.treeStarActive : ''}`}
+            onClick={handleStarClick}
+            tabIndex={-1}
+            aria-label={starred ? 'Remove from starred' : 'Add to starred'}
+          >
+            {starred ? <StarFilled /> : <StarOutline />}
+          </button>
+        )}
+      </div>
+
+      {/* Children */}
+      {hasChildren && isExpanded && (
+        <ul role="group" className={styles.treeGroup}>
+          {node.children!.map((child) => (
+            <SidebarTreeRow
+              key={child.id}
+              node={child}
+              depth={depth + 1}
+              expandedSet={expandedSet}
+              selectedPath={selectedPath}
+              focusedId={focusedId}
+              isStarred={isStarred}
+              onToggle={onToggle}
+              onToggleStar={onToggleStar}
+              onFocus={onFocus}
+              navigate={navigate}
+            />
+          ))}
+        </ul>
+      )}
+    </li>
+  )
+}
--- a/src/design-system/layout/Sidebar/useStarred.test.ts
+++ b/src/design-system/layout/Sidebar/useStarred.test.ts
@@ -0,0 +1,48 @@
+import { describe, it, expect, beforeEach } from 'vitest'
+import { renderHook, act } from '@testing-library/react'
+import { useStarred } from './useStarred'
+
+describe('useStarred', () => {
+  beforeEach(() => {
+    localStorage.clear()
+  })
+
+  it('starts with empty set when no localStorage data', () => {
+    const { result } = renderHook(() => useStarred())
+    expect(result.current.starredIds.size).toBe(0)
+  })
+
+  it('toggleStar adds an item', () => {
+    const { result } = renderHook(() => useStarred())
+    act(() => { result.current.toggleStar('app-1') })
+    expect(result.current.isStarred('app-1')).toBe(true)
+    expect(result.current.starredIds.size).toBe(1)
+  })
+
+  it('toggleStar removes a starred item', () => {
+    const { result } = renderHook(() => useStarred())
+    act(() => { result.current.toggleStar('app-1') })
+    act(() => { result.current.toggleStar('app-1') })
+    expect(result.current.isStarred('app-1')).toBe(false)
+  })
+
+  it('persists to localStorage', () => {
+    const { result } = renderHook(() => useStarred())
+    act(() => { result.current.toggleStar('route-1') })
+    const stored = JSON.parse(localStorage.getItem('cameleer:starred') ?? '[]')
+    expect(stored).toContain('route-1')
+  })
+
+  it('reads from localStorage on mount', () => {
+    localStorage.setItem('cameleer:starred', JSON.stringify(['agent-1', 'route-2']))
+    const { result } = renderHook(() => useStarred())
+    expect(result.current.isStarred('agent-1')).toBe(true)
+    expect(result.current.isStarred('route-2')).toBe(true)
+  })
+
+  it('handles corrupted localStorage gracefully', () => {
+    localStorage.setItem('cameleer:starred', 'not-valid-json')
+    const { result } = renderHook(() => useStarred())
+    expect(result.current.starredIds.size).toBe(0)
+  })
+})
--- a/src/design-system/layout/Sidebar/useStarred.ts
+++ b/src/design-system/layout/Sidebar/useStarred.ts
@@ -0,0 +1,45 @@
+import { useState, useCallback } from 'react'
+
+const STORAGE_KEY = 'cameleer:starred'
+
+function readStarred(): Set<string> {
+  try {
+    const raw = localStorage.getItem(STORAGE_KEY)
+    if (raw) {
+      const arr = JSON.parse(raw)
+      if (Array.isArray(arr)) return new Set(arr)
+    }
+  } catch {
+    // localStorage unavailable (private browsing, quota exceeded) — fall back to empty
+  }
+  return new Set()
+}
+
+function writeStarred(ids: Set<string>): void {
+  try {
+    localStorage.setItem(STORAGE_KEY, JSON.stringify([...ids]))
+  } catch {
+    // Silently fail if localStorage unavailable
+  }
+}
+
+export function useStarred() {
+  const [starredIds, setStarredIds] = useState<Set<string>>(readStarred)
+
+  const isStarred = useCallback((id: string) => starredIds.has(id), [starredIds])
+
+  const toggleStar = useCallback((id: string) => {
+    setStarredIds((prev) => {
+      const next = new Set(prev)
+      if (next.has(id)) {
+        next.delete(id)
+      } else {
+        next.add(id)
+      }
+      writeStarred(next)
+      return next
+    })
+  }, [])
+
+  return { starredIds, isStarred, toggleStar }
+}
--- a/src/design-system/layout/index.ts
+++ b/src/design-system/layout/index.ts
@@ -1,4 +1,4 @@
 export { AppShell } from './AppShell/AppShell'
 export { Sidebar } from './Sidebar/Sidebar'
-export type { App, Route, Agent } from './Sidebar/Sidebar'
+export type { SidebarApp, SidebarRoute, SidebarAgent } from './Sidebar/Sidebar'
 export { TopBar } from './TopBar/TopBar'
--- a/src/mocks/agents.ts
+++ b/src/mocks/agents.ts
@@ -1,6 +1,12 @@
-import type { Agent } from '../design-system/layout/Sidebar/Sidebar'
-
-export interface AgentHealth extends Agent {
+export interface AgentHealth {
+  id: string
+  name: string
+  service: string
+  version: string
+  tps: string
+  lastSeen: string
+  status: 'live' | 'stale' | 'dead'
+  errorRate?: string
  uptime: string
  memoryUsagePct: number
  cpuUsagePct: number
--- a/src/mocks/sidebar.ts
+++ b/src/mocks/sidebar.ts
@@ -0,0 +1,75 @@
+export interface SidebarRoute {
+  id: string
+  name: string
+  exchangeCount: number
+}
+
+export interface SidebarAgent {
+  id: string
+  name: string
+  status: 'live' | 'stale' | 'dead'
+  tps: string
+}
+
+export interface SidebarApp {
+  id: string
+  name: string
+  health: 'live' | 'stale' | 'dead'
+  exchangeCount: number
+  routes: SidebarRoute[]
+  agents: SidebarAgent[]
+}
+
+export const SIDEBAR_APPS: SidebarApp[] = [
+  {
+    id: 'order-service',
+    name: 'order-service',
+    health: 'live',
+    exchangeCount: 1433,
+    routes: [
+      { id: 'order-intake', name: 'order-intake', exchangeCount: 892 },
+      { id: 'order-enrichment', name: 'order-enrichment', exchangeCount: 541 },
+    ],
+    agents: [
+      { id: 'prod-1', name: 'prod-1', status: 'live', tps: '14.2/s' },
+      { id: 'prod-2', name: 'prod-2', status: 'live', tps: '11.8/s' },
+    ],
+  },
+  {
+    id: 'payment-svc',
+    name: 'payment-svc',
+    health: 'live',
+    exchangeCount: 912,
+    routes: [
+      { id: 'payment-process', name: 'payment-process', exchangeCount: 414 },
+      { id: 'payment-validate', name: 'payment-validate', exchangeCount: 498 },
+    ],
+    agents: [
+      { id: 'prod-2', name: 'prod-2', status: 'live', tps: '11.8/s' },
+    ],
+  },
+  {
+    id: 'shipment-tracker',
+    name: 'shipment-tracker',
+    health: 'live',
+    exchangeCount: 471,
+    routes: [
+      { id: 'shipment-dispatch', name: 'shipment-dispatch', exchangeCount: 387 },
+      { id: 'shipment-track', name: 'shipment-track', exchangeCount: 923 },
+    ],
+    agents: [
+      { id: 'prod-3', name: 'prod-3', status: 'live', tps: '12.1/s' },
+      { id: 'prod-4', name: 'prod-4', status: 'live', tps: '9.1/s' },
+    ],
+  },
+  {
+    id: 'notification-hub',
+    name: 'notification-hub',
+    health: 'stale',
+    exchangeCount: 128,
+    routes: [
+      { id: 'notification-dispatch', name: 'notification-dispatch', exchangeCount: 471 },
+    ],
+    agents: [],
+  },
+]
--- a/src/pages/Admin/Admin.tsx
+++ b/src/pages/Admin/Admin.tsx
@@ -0,0 +1,22 @@
+import { AppShell } from '../../design-system/layout/AppShell/AppShell'
+import { Sidebar } from '../../design-system/layout/Sidebar/Sidebar'
+import { TopBar } from '../../design-system/layout/TopBar/TopBar'
+import { EmptyState } from '../../design-system/primitives/EmptyState/EmptyState'
+import { SIDEBAR_APPS } from '../../mocks/sidebar'
+
+export function Admin() {
+  return (
+    <AppShell sidebar={<Sidebar apps={SIDEBAR_APPS} />}>
+      <TopBar
+        breadcrumb={[{ label: 'Admin' }]}
+        environment="PRODUCTION"
+        shift="Day (06:00-18:00)"
+        user={{ name: 'hendrik' }}
+      />
+      <EmptyState
+        title="Admin Panel"
+        description="Admin panel coming soon."
+      />
+    </AppShell>
+  )
+}
--- a/src/pages/AgentDetail/AgentDetail.tsx
+++ b/src/pages/AgentDetail/AgentDetail.tsx
@@ -0,0 +1,28 @@
+import { useParams } from 'react-router-dom'
+import { AppShell } from '../../design-system/layout/AppShell/AppShell'
+import { Sidebar } from '../../design-system/layout/Sidebar/Sidebar'
+import { TopBar } from '../../design-system/layout/TopBar/TopBar'
+import { EmptyState } from '../../design-system/primitives/EmptyState/EmptyState'
+import { SIDEBAR_APPS } from '../../mocks/sidebar'
+
+export function AgentDetail() {
+  const { id } = useParams<{ id: string }>()
+
+  return (
+    <AppShell sidebar={<Sidebar apps={SIDEBAR_APPS} />}>
+      <TopBar
+        breadcrumb={[
+          { label: 'Agents', href: '/agents' },
+          { label: id ?? '' },
+        ]}
+        environment="PRODUCTION"
+        shift="Day (06:00-18:00)"
+        user={{ name: 'hendrik' }}
+      />
+      <EmptyState
+        title="Agent Detail"
+        description="Agent detail view coming soon."
+      />
+    </AppShell>
+  )
+}
--- a/src/pages/AgentHealth/AgentHealth.tsx
+++ b/src/pages/AgentHealth/AgentHealth.tsx
@@ -1,5 +1,4 @@
 import { useState } from 'react'
-import { useNavigate } from 'react-router-dom'
 import styles from './AgentHealth.module.css'

 // Layout
@@ -18,21 +17,7 @@ import { Card } from '../../design-system/primitives/Card/Card'

 // Mock data
 import { agents } from '../../mocks/agents'
-import { routes } from '../../mocks/routes'
-
-// ─── Sidebar data (shared) ────────────────────────────────────────────────────
-const APPS = [
-  { id: 'order-service', name: 'order-service', agentCount: 2, health: 'live' as const, exchangeCount: 1433 },
-  { id: 'payment-svc', name: 'payment-svc', agentCount: 1, health: 'live' as const, exchangeCount: 912 },
-  { id: 'shipment-tracker', name: 'shipment-tracker', agentCount: 2, health: 'live' as const, exchangeCount: 471 },
-  { id: 'notification-hub', name: 'notification-hub', agentCount: 1, health: 'stale' as const, exchangeCount: 128 },
-]
-
-const SIDEBAR_ROUTES = routes.slice(0, 3).map((r) => ({
-  id: r.id,
-  name: r.name,
-  exchangeCount: r.exchangeCount,
-}))
+import { SIDEBAR_APPS } from '../../mocks/sidebar'

 // ─── Build trend data for each agent ─────────────────────────────────────────
 function buildAgentTrendSeries(agentId: string) {
@@ -68,16 +53,8 @@ const totalActiveRoutes = agents.reduce((sum, a) => sum + a.activeRoutes, 0)

 // ─── AgentHealth page ─────────────────────────────────────────────────────────
 export function AgentHealth() {
-  const navigate = useNavigate()
-  const [activeItem, setActiveItem] = useState('agents')
  const [expandedAgent, setExpandedAgent] = useState<string | null>(null)

-  function handleItemClick(id: string) {
-    setActiveItem(id)
-    const route = routes.find((r) => r.id === id)
-    if (route) navigate(`/routes/${id}`)
-  }
-
  function toggleAgent(id: string) {
    setExpandedAgent((prev) => (prev === id ? null : id))
  }
@@ -85,13 +62,7 @@ export function AgentHealth() {
  return (
    <AppShell
      sidebar={
-        <Sidebar
-          apps={APPS}
-          routes={SIDEBAR_ROUTES}
-          agents={agents}
-          activeItem={activeItem}
-          onItemClick={handleItemClick}
-        />
+        <Sidebar apps={SIDEBAR_APPS} />
      }
    >
      {/* Top bar */}
--- a/src/pages/ApiDocs/ApiDocs.tsx
+++ b/src/pages/ApiDocs/ApiDocs.tsx
@@ -0,0 +1,22 @@
+import { AppShell } from '../../design-system/layout/AppShell/AppShell'
+import { Sidebar } from '../../design-system/layout/Sidebar/Sidebar'
+import { TopBar } from '../../design-system/layout/TopBar/TopBar'
+import { EmptyState } from '../../design-system/primitives/EmptyState/EmptyState'
+import { SIDEBAR_APPS } from '../../mocks/sidebar'
+
+export function ApiDocs() {
+  return (
+    <AppShell sidebar={<Sidebar apps={SIDEBAR_APPS} />}>
+      <TopBar
+        breadcrumb={[{ label: 'API Documentation' }]}
+        environment="PRODUCTION"
+        shift="Day (06:00-18:00)"
+        user={{ name: 'hendrik' }}
+      />
+      <EmptyState
+        title="API Documentation"
+        description="API documentation coming soon."
+      />
+    </AppShell>
+  )
+}
--- a/src/pages/AppDetail/AppDetail.tsx
+++ b/src/pages/AppDetail/AppDetail.tsx
@@ -0,0 +1,28 @@
+import { useParams } from 'react-router-dom'
+import { AppShell } from '../../design-system/layout/AppShell/AppShell'
+import { Sidebar } from '../../design-system/layout/Sidebar/Sidebar'
+import { TopBar } from '../../design-system/layout/TopBar/TopBar'
+import { EmptyState } from '../../design-system/primitives/EmptyState/EmptyState'
+import { SIDEBAR_APPS } from '../../mocks/sidebar'
+
+export function AppDetail() {
+  const { id } = useParams<{ id: string }>()
+
+  return (
+    <AppShell sidebar={<Sidebar apps={SIDEBAR_APPS} />}>
+      <TopBar
+        breadcrumb={[
+          { label: 'Applications', href: '/' },
+          { label: id ?? '' },
+        ]}
+        environment="PRODUCTION"
+        shift="Day (06:00-18:00)"
+        user={{ name: 'hendrik' }}
+      />
+      <EmptyState
+        title="Application Detail"
+        description="Application detail view coming soon."
+      />
+    </AppShell>
+  )
+}
--- a/src/pages/Dashboard/Dashboard.tsx
+++ b/src/pages/Dashboard/Dashboard.tsx
@@ -28,21 +28,7 @@ import { exchanges, type Exchange } from '../../mocks/exchanges'
 import { routes } from '../../mocks/routes'
 import { agents } from '../../mocks/agents'
 import { kpiMetrics } from '../../mocks/metrics'
-
-// ─── Sidebar app list (static) ───────────────────────────────────────────────
-const APPS = [
-  { id: 'order-service', name: 'order-service', agentCount: 2, health: 'live' as const, exchangeCount: 1433 },
-  { id: 'payment-svc', name: 'payment-svc', agentCount: 1, health: 'live' as const, exchangeCount: 912 },
-  { id: 'shipment-tracker', name: 'shipment-tracker', agentCount: 2, health: 'live' as const, exchangeCount: 471 },
-  { id: 'notification-hub', name: 'notification-hub', agentCount: 1, health: 'stale' as const, exchangeCount: 128 },
-]
-
-// ─── Sidebar routes (top 3) ───────────────────────────────────────────────────
-const SIDEBAR_ROUTES = routes.slice(0, 3).map((r) => ({
-  id: r.id,
-  name: r.name,
-  exchangeCount: r.exchangeCount,
-}))
+import { SIDEBAR_APPS } from '../../mocks/sidebar'

 // ─── Helpers ─────────────────────────────────────────────────────────────────
 function formatDuration(ms: number): string {
@@ -208,7 +194,6 @@ const SHORTCUTS = [

 // ─── Dashboard component ──────────────────────────────────────────────────────
 export function Dashboard() {
-  const [activeItem, setActiveItem] = useState('order-service')
  const [activeFilters, setActiveFilters] = useState<ActiveFilter[]>([])
  const [search, setSearch] = useState('')
  const [selectedId, setSelectedId] = useState<string | undefined>()
@@ -349,13 +334,7 @@ export function Dashboard() {
  return (
    <AppShell
      sidebar={
-        <Sidebar
-          apps={APPS}
-          routes={SIDEBAR_ROUTES}
-          agents={agents}
-          activeItem={activeItem}
-          onItemClick={setActiveItem}
-        />
+        <Sidebar apps={SIDEBAR_APPS} />
      }
      detail={
        selectedExchange ? (
--- a/src/pages/ExchangeDetail/ExchangeDetail.tsx
+++ b/src/pages/ExchangeDetail/ExchangeDetail.tsx
@@ -1,4 +1,4 @@
-import { useMemo, useState } from 'react'
+import { useMemo } from 'react'
 import { useParams, useNavigate } from 'react-router-dom'
 import styles from './ExchangeDetail.module.css'

@@ -21,22 +21,7 @@ import { InfoCallout } from '../../design-system/primitives/InfoCallout/InfoCall

 // Mock data
 import { exchanges } from '../../mocks/exchanges'
-import { routes } from '../../mocks/routes'
-import { agents } from '../../mocks/agents'
-
-// ─── Sidebar data (shared) ────────────────────────────────────────────────────
-const APPS = [
-  { id: 'order-service', name: 'order-service', agentCount: 2, health: 'live' as const, exchangeCount: 1433 },
-  { id: 'payment-svc', name: 'payment-svc', agentCount: 1, health: 'live' as const, exchangeCount: 912 },
-  { id: 'shipment-tracker', name: 'shipment-tracker', agentCount: 2, health: 'live' as const, exchangeCount: 471 },
-  { id: 'notification-hub', name: 'notification-hub', agentCount: 1, health: 'stale' as const, exchangeCount: 128 },
-]
-
-const SIDEBAR_ROUTES = routes.slice(0, 3).map((r) => ({
-  id: r.id,
-  name: r.name,
-  exchangeCount: r.exchangeCount,
-}))
+import { SIDEBAR_APPS } from '../../mocks/sidebar'

 // ─── Helpers ──────────────────────────────────────────────────────────────────
 function formatDuration(ms: number): string {
@@ -119,28 +104,15 @@ function generateExchangeSnapshot(
 export function ExchangeDetail() {
  const { id } = useParams<{ id: string }>()
  const navigate = useNavigate()
-  const [activeItem, setActiveItem] = useState('')

  const exchange = useMemo(() => exchanges.find((e) => e.id === id), [id])

-  function handleItemClick(itemId: string) {
-    setActiveItem(itemId)
-    const route = routes.find((r) => r.id === itemId)
-    if (route) navigate(`/routes/${itemId}`)
-  }
-
  // Not found state
  if (!exchange) {
    return (
      <AppShell
        sidebar={
-          <Sidebar
-            apps={APPS}
-            routes={SIDEBAR_ROUTES}
-            agents={agents}
-            activeItem={activeItem}
-            onItemClick={handleItemClick}
-          />
+          <Sidebar apps={SIDEBAR_APPS} />
        }
      >
        <TopBar
@@ -166,13 +138,7 @@ export function ExchangeDetail() {
  return (
    <AppShell
      sidebar={
-        <Sidebar
-          apps={APPS}
-          routes={SIDEBAR_ROUTES}
-          agents={agents}
-          activeItem={activeItem}
-          onItemClick={handleItemClick}
-        />
+        <Sidebar apps={SIDEBAR_APPS} />
      }
    >
      {/* Top bar */}
--- a/src/pages/Inventory/sections/LayoutSection.tsx
+++ b/src/pages/Inventory/sections/LayoutSection.tsx
@@ -1,5 +1,6 @@
 import styles from './LayoutSection.module.css'
 import { Sidebar } from '../../../design-system/layout/Sidebar/Sidebar'
+import type { SidebarApp } from '../../../design-system/layout/Sidebar/Sidebar'
 import { TopBar } from '../../../design-system/layout/TopBar/TopBar'

 // ── DemoCard helper ──────────────────────────────────────────────────────────
@@ -21,48 +22,42 @@ function DemoCard({ id, title, description, children }: DemoCardProps) {
  )
 }

-// ── Sample data ───────────────────────────────────────────────────────────────
+// ── Sample data (hierarchical) ───────────────────────────────────────────────

-const SAMPLE_APPS = [
-  { id: 'app1', name: 'cameleer-prod', agentCount: 3, health: 'live' as const, exchangeCount: 14320 },
-  { id: 'app2', name: 'cameleer-staging', agentCount: 2, health: 'stale' as const, exchangeCount: 871 },
-  { id: 'app3', name: 'cameleer-dev', agentCount: 1, health: 'dead' as const, exchangeCount: 42 },
-]
-
-const SAMPLE_ROUTES = [
-  { id: 'r1', name: 'order-ingest', exchangeCount: 5421 },
-  { id: 'r2', name: 'payment-validate', exchangeCount: 3102 },
-  { id: 'r3', name: 'notify-customer', exchangeCount: 2201 },
-]
-
-const SAMPLE_AGENTS = [
+const SAMPLE_APPS: SidebarApp[] = [
  {
-    id: 'ag1',
-    name: 'agent-prod-1',
-    service: 'camel-core',
-    version: 'v3.2.1',
-    tps: '42 tps',
-    lastSeen: '1m ago',
-    status: 'live' as const,
+    id: 'app1',
+    name: 'cameleer-prod',
+    health: 'live' as const,
+    exchangeCount: 14320,
+    routes: [
+      { id: 'r1', name: 'order-ingest', exchangeCount: 5421 },
+      { id: 'r2', name: 'payment-validate', exchangeCount: 3102 },
+    ],
+    agents: [
+      { id: 'ag1', name: 'agent-prod-1', status: 'live' as const, tps: '42 tps' },
+      { id: 'ag2', name: 'agent-prod-2', status: 'live' as const, tps: '38 tps' },
+    ],
  },
  {
-    id: 'ag2',
-    name: 'agent-prod-2',
-    service: 'camel-core',
-    version: 'v3.2.1',
-    tps: '38 tps',
-    lastSeen: '2m ago',
-    status: 'live' as const,
-    errorRate: '0.4%',
+    id: 'app2',
+    name: 'cameleer-staging',
+    health: 'stale' as const,
+    exchangeCount: 871,
+    routes: [
+      { id: 'r3', name: 'notify-customer', exchangeCount: 2201 },
+    ],
+    agents: [
+      { id: 'ag3', name: 'agent-staging-1', status: 'stale' as const, tps: '5 tps' },
+    ],
  },
  {
-    id: 'ag3',
-    name: 'agent-staging-1',
-    service: 'camel-core',
-    version: 'v3.1.9',
-    tps: '5 tps',
-    lastSeen: '8m ago',
-    status: 'stale' as const,
+    id: 'app3',
+    name: 'cameleer-dev',
+    health: 'dead' as const,
+    exchangeCount: 42,
+    routes: [],
+    agents: [],
  },
 ]

@@ -89,9 +84,9 @@ export function LayoutSection() {
              <span style={{ fontWeight: 400, fontSize: 10, marginTop: 4 }}>Logo</span>
              <span style={{ fontWeight: 400, fontSize: 10 }}>Search</span>
              <span style={{ fontWeight: 400, fontSize: 10 }}>Navigation</span>
-              <span style={{ fontWeight: 400, fontSize: 10 }}>Applications</span>
-              <span style={{ fontWeight: 400, fontSize: 10 }}>Routes</span>
-              <span style={{ fontWeight: 400, fontSize: 10 }}>Agents</span>
+              <span style={{ fontWeight: 400, fontSize: 10 }}>Applications tree</span>
+              <span style={{ fontWeight: 400, fontSize: 10 }}>Agents tree</span>
+              <span style={{ fontWeight: 400, fontSize: 10 }}>Starred</span>
            </div>
            <div className={styles.shellDiagramMain}>
              &lt;children&gt; — page content rendered here
@@ -104,14 +99,10 @@ export function LayoutSection() {
      <DemoCard
        id="sidebar"
        title="Sidebar"
-        description="Navigation sidebar with app/route/agent sections, search filter, health dots, and exec counts."
+        description="Navigation sidebar with hierarchical app/route/agent trees, starring, search filter, and bottom links."
      >
        <div className={styles.sidebarPreview}>
-          <Sidebar
-            apps={SAMPLE_APPS}
-            routes={SAMPLE_ROUTES}
-            agents={SAMPLE_AGENTS}
-          />
+          <Sidebar apps={SAMPLE_APPS} />
        </div>
      </DemoCard>

--- a/src/pages/Metrics/Metrics.tsx
+++ b/src/pages/Metrics/Metrics.tsx
@@ -29,22 +29,7 @@ import {
  routeMetrics,
  type RouteMetricRow,
 } from '../../mocks/metrics'
-import { routes } from '../../mocks/routes'
-import { agents } from '../../mocks/agents'
-
-// ─── Sidebar data (shared) ────────────────────────────────────────────────────
-const APPS = [
-  { id: 'order-service', name: 'order-service', agentCount: 2, health: 'live' as const, exchangeCount: 1433 },
-  { id: 'payment-svc', name: 'payment-svc', agentCount: 1, health: 'live' as const, exchangeCount: 912 },
-  { id: 'shipment-tracker', name: 'shipment-tracker', agentCount: 2, health: 'live' as const, exchangeCount: 471 },
-  { id: 'notification-hub', name: 'notification-hub', agentCount: 1, health: 'stale' as const, exchangeCount: 128 },
-]
-
-const SIDEBAR_ROUTES = routes.slice(0, 3).map((r) => ({
-  id: r.id,
-  name: r.name,
-  exchangeCount: r.exchangeCount,
-}))
+import { SIDEBAR_APPS } from '../../mocks/sidebar'

 // ─── Metrics KPI cards (5 cards per spec) ─────────────────────────────────────
 const METRIC_KPIS = [
@@ -207,29 +192,15 @@ function convertSeries(series: typeof throughputSeries) {
 // ─── Metrics page ─────────────────────────────────────────────────────────────
 export function Metrics() {
  const navigate = useNavigate()
-  const [activeItem, setActiveItem] = useState('order-service')
  const [dateRange, setDateRange] = useState({
    start: new Date('2026-03-18T06:00:00'),
    end: new Date('2026-03-18T09:15:00'),
  })

-  function handleItemClick(id: string) {
-    setActiveItem(id)
-    // Navigate to route detail if it's a route
-    const route = routes.find((r) => r.id === id)
-    if (route) navigate(`/routes/${id}`)
-  }
-
  return (
    <AppShell
      sidebar={
-        <Sidebar
-          apps={APPS}
-          routes={SIDEBAR_ROUTES}
-          agents={agents}
-          activeItem={activeItem}
-          onItemClick={handleItemClick}
-        />
+        <Sidebar apps={SIDEBAR_APPS} />
      }
    >
      {/* Top bar */}
--- a/src/pages/RouteDetail/RouteDetail.tsx
+++ b/src/pages/RouteDetail/RouteDetail.tsx
@@ -1,4 +1,4 @@
-import { useMemo, useState } from 'react'
+import { useMemo } from 'react'
 import { useParams, useNavigate } from 'react-router-dom'
 import styles from './RouteDetail.module.css'

@@ -21,21 +21,7 @@ import { InfoCallout } from '../../design-system/primitives/InfoCallout/InfoCall
 // Mock data
 import { routes } from '../../mocks/routes'
 import { exchanges, type Exchange } from '../../mocks/exchanges'
-import { agents } from '../../mocks/agents'
-
-// ─── Sidebar data (shared) ────────────────────────────────────────────────────
-const APPS = [
-  { id: 'order-service', name: 'order-service', agentCount: 2, health: 'live' as const, exchangeCount: 1433 },
-  { id: 'payment-svc', name: 'payment-svc', agentCount: 1, health: 'live' as const, exchangeCount: 912 },
-  { id: 'shipment-tracker', name: 'shipment-tracker', agentCount: 2, health: 'live' as const, exchangeCount: 471 },
-  { id: 'notification-hub', name: 'notification-hub', agentCount: 1, health: 'stale' as const, exchangeCount: 128 },
-]
-
-const SIDEBAR_ROUTES = routes.slice(0, 3).map((r) => ({
-  id: r.id,
-  name: r.name,
-  exchangeCount: r.exchangeCount,
-}))
+import { SIDEBAR_APPS } from '../../mocks/sidebar'

 // ─── Helpers ──────────────────────────────────────────────────────────────────
 function formatDuration(ms: number): string {
@@ -143,7 +129,6 @@ const EXCHANGE_COLUMNS: Column<Exchange>[] = [
 export function RouteDetail() {
  const { id } = useParams<{ id: string }>()
  const navigate = useNavigate()
-  const [activeItem, setActiveItem] = useState(id ?? '')

  const route = useMemo(() => routes.find((r) => r.id === id), [id])
  const routeExchanges = useMemo(
@@ -210,24 +195,12 @@ export function RouteDetail() {
    ? ((successCount / routeExchanges.length) * 100).toFixed(1)
    : '0.0'

-  function handleItemClick(itemId: string) {
-    setActiveItem(itemId)
-    const r = routes.find((route) => route.id === itemId)
-    if (r) navigate(`/routes/${itemId}`)
-  }
-
  // Not found state
  if (!route) {
    return (
      <AppShell
        sidebar={
-          <Sidebar
-            apps={APPS}
-            routes={SIDEBAR_ROUTES}
-            agents={agents}
-            activeItem={activeItem}
-            onItemClick={handleItemClick}
-          />
+          <Sidebar apps={SIDEBAR_APPS} />
        }
      >
        <TopBar
@@ -252,13 +225,7 @@ export function RouteDetail() {
  return (
    <AppShell
      sidebar={
-        <Sidebar
-          apps={APPS}
-          routes={SIDEBAR_ROUTES}
-          agents={agents}
-          activeItem={activeItem}
-          onItemClick={handleItemClick}
-        />
+        <Sidebar apps={SIDEBAR_APPS} />
      }
    >
      {/* Top bar */}