diff --git a/src/app/layout.tsx b/src/app/layout.tsx
index 0d7a407..e9545eb 100755
--- a/src/app/layout.tsx
+++ b/src/app/layout.tsx
@@ -2,6 +2,7 @@ import type { Metadata } from "next";
 import { Geist, Geist_Mono } from "next/font/google";
 import "./globals.css";
 import { Toaster } from "@/components/ui/toaster";
+import { APP_NAME, APP_SHORT, APP_VERSION } from "@/lib/version";
 
 const geistSans = Geist({
   variable: "--font-geist-sans",
@@ -14,10 +15,10 @@ const geistMono = Geist_Mono({
 });
 
 export const metadata: Metadata = {
-  title: "AVA — Advanced Visualization Agent",
+  title: `${APP_SHORT} — ${APP_NAME} (v${APP_VERSION})`,
   description:
-    "Audio-reactive visualization agent for clubs: 3-band spectrum detection, predictive beat tracking and AVS-style visualization scripting.",
-  keywords: ["AVA", "visualization", "VJ", "audio-reactive", "beat detection", "AVS", "Winamp"],
+    "Open Visualization Engine: audio-reactive visuals for clubs — 3-band spectrum detection, predictive beat tracking and AVS-style visualization scripting.",
+  keywords: ["OVE", "visualization", "VJ", "audio-reactive", "beat detection", "AVS", "Winamp"],
   icons: {
     icon: "/logo.svg",
   },
diff --git a/src/components/ava/footer-bar.tsx b/src/components/ava/footer-bar.tsx
index 698ae23..ece12fb 100755
--- a/src/components/ava/footer-bar.tsx
+++ b/src/components/ava/footer-bar.tsx
@@ -1,8 +1,9 @@
-// AVA — sticky footer status bar: micro-stats + engine health.
+// OVE — sticky footer status bar: micro-stats + version stamp + engine health.
 
 'use client'
 
 import { useAvaStore } from '@/lib/store'
+import { APP_NAME, APP_VERSION } from '@/lib/version'
 import { cn } from '@/lib/utils'
 
 export function FooterBar() {
@@ -45,16 +46,25 @@ export function FooterBar() {
           SCRIPT: <span className="ml-1 truncate text-zinc-300">{scriptName}</span>
         </span>
 
-        <span className={cn('ml-auto flex shrink-0 items-center gap-1.5', error ? 'text-rose-400' : 'text-emerald-400')}>
+        {/* version stamp (left of the engine-health dot) + engine health */}
+        <div className="ml-auto flex shrink-0 items-center gap-3 sm:gap-4">
           <span
-            className={cn(
-              'size-1.5 rounded-full',
-              error ? 'animate-pulse bg-rose-400 shadow-[0_0_8px_rgba(251,113,133,0.8)]' : 'bg-emerald-400 shadow-[0_0_8px_rgba(52,211,153,0.8)]',
-            )}
-            aria-hidden
-          />
-          <span className="text-zinc-400">{error ? 'script error' : 'engine ok'}</span>
-        </span>
+            className="text-zinc-600"
+            title={`${APP_NAME} — version ${APP_VERSION}`}
+          >
+            version {APP_VERSION}
+          </span>
+          <span className={cn('flex items-center gap-1.5', error ? 'text-rose-400' : 'text-emerald-400')}>
+            <span
+              className={cn(
+                'size-1.5 rounded-full',
+                error ? 'animate-pulse bg-rose-400 shadow-[0_0_8px_rgba(251,113,133,0.8)]' : 'bg-emerald-400 shadow-[0_0_8px_rgba(52,211,153,0.8)]',
+              )}
+              aria-hidden
+            />
+            <span className="text-zinc-400">{error ? 'script error' : 'engine ok'}</span>
+          </span>
+        </div>
       </div>
     </footer>
   )
diff --git a/src/components/ava/header.tsx b/src/components/ava/header.tsx
index 7b86997..357c1b6 100755
--- a/src/components/ava/header.tsx
+++ b/src/components/ava/header.tsx
@@ -12,6 +12,7 @@ import { BeatDot } from '@/components/ava/beat-dot'
 import { LinkDialog } from '@/components/ava/link-dialog'
 import { tapBeat, useAudioSource } from '@/components/ava/audio-source'
 import { useAvaStore } from '@/lib/store'
+import { APP_NAME, APP_SHORT } from '@/lib/version'
 import { cn } from '@/lib/utils'
 
 function SourceSegmentButton({
@@ -149,9 +150,9 @@ export function AppHeader() {
             <AudioWaveform className="size-5 text-zinc-950" aria-hidden />
           </div>
           <div>
-            <h1 className="text-base font-bold leading-none tracking-wide">AVA</h1>
+            <h1 className="text-base font-bold leading-none tracking-wide">{APP_SHORT}</h1>
             <p className="mt-1 hidden text-[10px] leading-none tracking-[0.14em] text-zinc-500 sm:block">
-              ADVANCED VISUALIZATION AGENT
+              {APP_NAME.toUpperCase()}
             </p>
           </div>
         </div>
diff --git a/src/lib/version.ts b/src/lib/version.ts
new file mode 100644
index 0000000..1328fde
--- /dev/null
+++ b/src/lib/version.ts
@@ -0,0 +1,16 @@
+// OVE — app identity + version stamp.
+//
+// Single source of truth for the product name and version shown in the UI
+// (header, footer, document title). Bump APP_VERSION whenever we ship a
+// large change so the running build can always be identified at a glance —
+// useful both for the z.ai Version History and for naming local backups
+// (v6.0 = rename to Open Visualization Engine + version indicator).
+//
+// History:
+//   6.0 — renamed to "Open Visualization Engine" + footer version stamp
+//   5.0 — folder-tree Presets page (Task 9–11 state, restored in Task 12)
+//   4.0 — link audio source (yt-dlp resolve + stream proxy)
+
+export const APP_NAME = 'Open Visualization Engine'
+export const APP_SHORT = 'OVE'
+export const APP_VERSION = '6.0'
diff --git a/tool-results/ove-v6-desktop.png b/tool-results/ove-v6-desktop.png
new file mode 100644
index 0000000..4907689
Binary files /dev/null and b/tool-results/ove-v6-desktop.png differ
diff --git a/tool-results/ove-v6-mobile.png b/tool-results/ove-v6-mobile.png
new file mode 100644
index 0000000..894e2c6
Binary files /dev/null and b/tool-results/ove-v6-mobile.png differ
diff --git a/worklog.md b/worklog.md
index 504f75e..d940bf1 100755
--- a/worklog.md
+++ b/worklog.md
@@ -728,3 +728,39 @@ Stage Summary:
   now matches the archive's HEAD (2a23db4) on top of the current workspace.
 - NOTE for the future: commit snapshots are the source of truth when an
   environment rebuild is suspected — compare git log before re-implementing.
+
+---
+Task ID: 13
+Agent: main (Z.ai Code)
+Task: v6.0 — rename to "Open Visualization Engine" (AVA → OVE) + footer
+version indicator (establishes the versioning convention)
+
+Work Log:
+- New src/lib/version.ts — single source of truth: APP_NAME
+  "Open Visualization Engine", APP_SHORT "OVE", APP_VERSION "6.0" + a
+  short version-history comment (6.0 rename+stamp, 5.0 folder-tree, 4.0
+  link source) so future bumps are a one-line change.
+- src/app/layout.tsx — document title now "OVE — Open Visualization Engine
+  (v6.0)" (built from the constants); description + keywords updated
+  (AVA→OVE, "agent"→"engine").
+- src/components/ava/header.tsx — logo block h1 "AVA" → "OVE" (APP_SHORT),
+  subtitle "ADVANCED VISUALIZATION AGENT" → "OPEN VISUALIZATION ENGINE"
+  (APP_NAME.toUpperCase()), both imported from version.ts.
+- src/components/ava/footer-bar.tsx — right cluster is now a ml-auto wrapper
+  holding: "version 6.0" stamp (text-zinc-600, tooltip "Open Visualization
+  Engine — version 6.0") immediately LEFT of the engine-ok dot + label,
+  exactly as requested. Stamp is visible on mobile too (fits: no horizontal
+  scroll at 390px).
+- Internal code identifiers (ava store/lib/component paths, ava-agent rust
+  crate) intentionally left unchanged — the rename is user-facing only.
+- VERIFIED in agent-browser: title "OVE — Open Visualization Engine (v6.0)";
+  header logo/subtitle; footer text "...version 6.0\nengine ok" with the
+  stamp on the same row, right of the stats, left of the dot; mobile 390×844
+  no horizontal scroll + stamp visible; zero console/page errors; lint clean.
+- Committed as "v6.0 — rename to Open Visualization Engine + version stamp".
+
+Stage Summary:
+- Versioning convention established: bump APP_VERSION in src/lib/version.ts
+  on every large change; the stamp renders bottom-right of the footer and the
+  document title carries it too. Users can name local backups by the stamp
+  (e.g. "OVE v6.0") and cross-check against z.ai Version History.