diff --git a/ui/src/i18n/.i18n/ar.meta.json b/ui/src/i18n/.i18n/ar.meta.json
index 52d65420420c..4276a2c0bd21 100644
--- a/ui/src/i18n/.i18n/ar.meta.json
+++ b/ui/src/i18n/.i18n/ar.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:07:21.796Z",
+  "generatedAt": "2026-06-29T17:06:18.945Z",
   "locale": "ar",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/de.meta.json b/ui/src/i18n/.i18n/de.meta.json
index cedeb690a7e5..bdb5954927c1 100644
--- a/ui/src/i18n/.i18n/de.meta.json
+++ b/ui/src/i18n/.i18n/de.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:06:02.374Z",
+  "generatedAt": "2026-06-29T17:06:17.867Z",
   "locale": "de",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/es.meta.json b/ui/src/i18n/.i18n/es.meta.json
index ead0e4cc5f07..238099037e84 100644
--- a/ui/src/i18n/.i18n/es.meta.json
+++ b/ui/src/i18n/.i18n/es.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:06:31.127Z",
+  "generatedAt": "2026-06-29T17:06:18.056Z",
   "locale": "es",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/fa.meta.json b/ui/src/i18n/.i18n/fa.meta.json
index 54e695a34ce6..d1c64e393676 100644
--- a/ui/src/i18n/.i18n/fa.meta.json
+++ b/ui/src/i18n/.i18n/fa.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:08:50.278Z",
+  "generatedAt": "2026-06-29T17:06:20.668Z",
   "locale": "fa",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/fr.meta.json b/ui/src/i18n/.i18n/fr.meta.json
index 89176a25f0c5..276752eb11d4 100644
--- a/ui/src/i18n/.i18n/fr.meta.json
+++ b/ui/src/i18n/.i18n/fr.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:06:59.616Z",
+  "generatedAt": "2026-06-29T17:06:18.559Z",
   "locale": "fr",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/hi.meta.json b/ui/src/i18n/.i18n/hi.meta.json
index 8746728be1d2..5cd4c45b8734 100644
--- a/ui/src/i18n/.i18n/hi.meta.json
+++ b/ui/src/i18n/.i18n/hi.meta.json
@@ -1,11 +1,14 @@
 {
-  "fallbackKeys": [],
-  "generatedAt": "2026-06-26T21:38:17.797Z",
+  "fallbackKeys": [
+    "chat.commentaryLabel",
+    "chat.commentaryToggle"
+  ],
+  "generatedAt": "2026-06-29T17:06:18.728Z",
   "locale": "hi",
   "model": "gpt-5.5",
   "provider": "openai",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
   "translatedKeys": 1416,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/id.meta.json b/ui/src/i18n/.i18n/id.meta.json
index fe0cfdc9953a..f5e3f84aa695 100644
--- a/ui/src/i18n/.i18n/id.meta.json
+++ b/ui/src/i18n/.i18n/id.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:08:00.729Z",
+  "generatedAt": "2026-06-29T17:06:19.737Z",
   "locale": "id",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/it.meta.json b/ui/src/i18n/.i18n/it.meta.json
index 89c5b56f5052..c5333f74586f 100644
--- a/ui/src/i18n/.i18n/it.meta.json
+++ b/ui/src/i18n/.i18n/it.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:07:12.745Z",
+  "generatedAt": "2026-06-29T17:06:19.156Z",
   "locale": "it",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/ja-JP.meta.json b/ui/src/i18n/.i18n/ja-JP.meta.json
index 0f001fbe3999..17a9c782385e 100644
--- a/ui/src/i18n/.i18n/ja-JP.meta.json
+++ b/ui/src/i18n/.i18n/ja-JP.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:06:34.355Z",
+  "generatedAt": "2026-06-29T17:06:18.241Z",
   "locale": "ja-JP",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/ko.meta.json b/ui/src/i18n/.i18n/ko.meta.json
index 4d97ed7a5839..ef118286a1c5 100644
--- a/ui/src/i18n/.i18n/ko.meta.json
+++ b/ui/src/i18n/.i18n/ko.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:06:42.132Z",
+  "generatedAt": "2026-06-29T17:06:18.409Z",
   "locale": "ko",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/nl.meta.json b/ui/src/i18n/.i18n/nl.meta.json
index 6d27b8c97a7b..8057e5340c45 100644
--- a/ui/src/i18n/.i18n/nl.meta.json
+++ b/ui/src/i18n/.i18n/nl.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:08:47.496Z",
+  "generatedAt": "2026-06-29T17:06:20.490Z",
   "locale": "nl",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/pl.meta.json b/ui/src/i18n/.i18n/pl.meta.json
index 7634fad71c51..d717c998f9b7 100644
--- a/ui/src/i18n/.i18n/pl.meta.json
+++ b/ui/src/i18n/.i18n/pl.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:08:08.174Z",
+  "generatedAt": "2026-06-29T17:06:19.915Z",
   "locale": "pl",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/pt-BR.meta.json b/ui/src/i18n/.i18n/pt-BR.meta.json
index 6036027ba115..7b2558de9230 100644
--- a/ui/src/i18n/.i18n/pt-BR.meta.json
+++ b/ui/src/i18n/.i18n/pt-BR.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:05:51.685Z",
+  "generatedAt": "2026-06-29T17:06:17.682Z",
   "locale": "pt-BR",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/raw-copy-baseline.json b/ui/src/i18n/.i18n/raw-copy-baseline.json
index 372a51a8f2cf..25afde2e5fc7 100644
--- a/ui/src/i18n/.i18n/raw-copy-baseline.json
+++ b/ui/src/i18n/.i18n/raw-copy-baseline.json
@@ -1513,6 +1513,13 @@
       "path": "ui/src/ui/views/channels.whatsapp.ts",
       "text": "WhatsApp"
     },
+    {
+      "count": 1,
+      "kind": "html-attribute",
+      "name": "aria-label",
+      "path": "ui/src/ui/views/chat.ts",
+      "text": "Cancel reply"
+    },
     {
       "count": 1,
       "kind": "html-attribute",
@@ -1597,6 +1604,13 @@
       "path": "ui/src/ui/views/chat.ts",
       "text": "Search messages..."
     },
+    {
+      "count": 1,
+      "kind": "html-attribute",
+      "name": "title",
+      "path": "ui/src/ui/views/chat.ts",
+      "text": "Cancel reply"
+    },
     {
       "count": 1,
       "kind": "html-attribute",
diff --git a/ui/src/i18n/.i18n/ru.meta.json b/ui/src/i18n/.i18n/ru.meta.json
index 5a8f849a4b07..ac7576594c5a 100644
--- a/ui/src/i18n/.i18n/ru.meta.json
+++ b/ui/src/i18n/.i18n/ru.meta.json
@@ -1,11 +1,14 @@
 {
-  "fallbackKeys": [],
-  "generatedAt": "2026-06-26T21:42:51.346Z",
+  "fallbackKeys": [
+    "chat.commentaryLabel",
+    "chat.commentaryToggle"
+  ],
+  "generatedAt": "2026-06-29T17:06:20.849Z",
   "locale": "ru",
   "model": "gpt-5.5",
   "provider": "openai",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
   "translatedKeys": 1416,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/th.meta.json b/ui/src/i18n/.i18n/th.meta.json
index 7c04686b8b22..f6448670acad 100644
--- a/ui/src/i18n/.i18n/th.meta.json
+++ b/ui/src/i18n/.i18n/th.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:08:16.442Z",
+  "generatedAt": "2026-06-29T17:06:20.099Z",
   "locale": "th",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/tr.meta.json b/ui/src/i18n/.i18n/tr.meta.json
index 6637e147efea..7a73b4e6a5dd 100644
--- a/ui/src/i18n/.i18n/tr.meta.json
+++ b/ui/src/i18n/.i18n/tr.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:07:26.912Z",
+  "generatedAt": "2026-06-29T17:06:19.344Z",
   "locale": "tr",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/uk.meta.json b/ui/src/i18n/.i18n/uk.meta.json
index 466fbf734427..317bad71b0b6 100644
--- a/ui/src/i18n/.i18n/uk.meta.json
+++ b/ui/src/i18n/.i18n/uk.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:07:50.082Z",
+  "generatedAt": "2026-06-29T17:06:19.546Z",
   "locale": "uk",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/vi.meta.json b/ui/src/i18n/.i18n/vi.meta.json
index ec9d6b2458f3..7fb172548c77 100644
--- a/ui/src/i18n/.i18n/vi.meta.json
+++ b/ui/src/i18n/.i18n/vi.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:08:44.881Z",
+  "generatedAt": "2026-06-29T17:06:20.308Z",
   "locale": "vi",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/zh-CN.meta.json b/ui/src/i18n/.i18n/zh-CN.meta.json
index 842ce9c62ee8..36087521588f 100644
--- a/ui/src/i18n/.i18n/zh-CN.meta.json
+++ b/ui/src/i18n/.i18n/zh-CN.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:05:51.877Z",
+  "generatedAt": "2026-06-29T17:06:17.341Z",
   "locale": "zh-CN",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/.i18n/zh-TW.meta.json b/ui/src/i18n/.i18n/zh-TW.meta.json
index 200c61b719c9..fa30d60dea3d 100644
--- a/ui/src/i18n/.i18n/zh-TW.meta.json
+++ b/ui/src/i18n/.i18n/zh-TW.meta.json
@@ -1,11 +1,11 @@
 {
   "fallbackKeys": [],
-  "generatedAt": "2026-06-26T22:05:54.449Z",
+  "generatedAt": "2026-06-29T17:06:17.519Z",
   "locale": "zh-TW",
   "model": "claude-opus-4-8",
   "provider": "anthropic",
-  "sourceHash": "08e6ec5c2e8416d0049d2452906c20d096e17e384299af89cde872f0cfbb5015",
-  "totalKeys": 1416,
-  "translatedKeys": 1416,
+  "sourceHash": "29f546ff372524aa64d09bd700f76899045da99552fa295a32eda9fad2a0407f",
+  "totalKeys": 1418,
+  "translatedKeys": 1418,
   "workflow": 1
 }
diff --git a/ui/src/i18n/locales/ar.ts b/ui/src/i18n/locales/ar.ts
index b57c79f36b99..8cfae182fb00 100644
--- a/ui/src/i18n/locales/ar.ts
+++ b/ui/src/i18n/locales/ar.ts
@@ -1313,6 +1313,8 @@ export const ar: TranslationMap = {
     settings: "إعدادات الدردشة",
     thinkingToggle: "تبديل مخرجات تفكير/عمل المساعد",
     toolCallsToggle: "تبديل استدعاءات الأدوات ونتائج الأدوات",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "وضع التمرير التلقائي",
     autoScrollAlways: "دائمًا",
     autoScrollNearBottom: "قرب الأسفل",
diff --git a/ui/src/i18n/locales/de.ts b/ui/src/i18n/locales/de.ts
index 963c8d5a8d90..8dd5bd3f8273 100644
--- a/ui/src/i18n/locales/de.ts
+++ b/ui/src/i18n/locales/de.ts
@@ -1340,6 +1340,8 @@ export const de: TranslationMap = {
     settings: "Chat-Einstellungen",
     thinkingToggle: "Ausgabe des Assistenten ein-/ausblenden",
     toolCallsToggle: "Tool-Aufrufe und Tool-Ergebnisse umschalten",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Automatischer Scrollmodus",
     autoScrollAlways: "Immer",
     autoScrollNearBottom: "Nahe am unteren Rand",
diff --git a/ui/src/i18n/locales/en.ts b/ui/src/i18n/locales/en.ts
index d9489bd82471..618ca38fad71 100644
--- a/ui/src/i18n/locales/en.ts
+++ b/ui/src/i18n/locales/en.ts
@@ -1319,6 +1319,8 @@ export const en: TranslationMap = {
     settings: "Chat settings",
     thinkingToggle: "Toggle assistant thinking/working output",
     toolCallsToggle: "Toggle tool calls and tool results",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Auto-scroll mode",
     autoScrollAlways: "Always",
     autoScrollNearBottom: "Near bottom",
diff --git a/ui/src/i18n/locales/es.ts b/ui/src/i18n/locales/es.ts
index 5f1cd78b1061..28f6e5e064f3 100644
--- a/ui/src/i18n/locales/es.ts
+++ b/ui/src/i18n/locales/es.ts
@@ -1337,6 +1337,8 @@ export const es: TranslationMap = {
     settings: "Configuración del chat",
     thinkingToggle: "Alternar salida de pensamiento/trabajo del asistente",
     toolCallsToggle: "Alternar llamadas a herramientas y resultados de herramientas",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Modo de desplazamiento automático",
     autoScrollAlways: "Siempre",
     autoScrollNearBottom: "Cerca del final",
diff --git a/ui/src/i18n/locales/fa.ts b/ui/src/i18n/locales/fa.ts
index 17b6cd588f1f..86967923d205 100644
--- a/ui/src/i18n/locales/fa.ts
+++ b/ui/src/i18n/locales/fa.ts
@@ -1331,6 +1331,8 @@ export const fa: TranslationMap = {
     settings: "تنظیمات چت",
     thinkingToggle: "تغییر وضعیت خروجی فکر/کار دستیار",
     toolCallsToggle: "تغییر وضعیت نمایش فراخوانی‌های ابزار و نتایج ابزار",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "حالت پیمایش خودکار",
     autoScrollAlways: "همیشه",
     autoScrollNearBottom: "نزدیک پایین",
diff --git a/ui/src/i18n/locales/fr.ts b/ui/src/i18n/locales/fr.ts
index 1418d2e6dc28..5cef695fae96 100644
--- a/ui/src/i18n/locales/fr.ts
+++ b/ui/src/i18n/locales/fr.ts
@@ -1344,6 +1344,8 @@ export const fr: TranslationMap = {
     settings: "Paramètres de chat",
     thinkingToggle: "Afficher/masquer la sortie de réflexion/travail de l’assistant",
     toolCallsToggle: "Afficher/masquer les appels d’outil et les résultats d’outil",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Mode de défilement automatique",
     autoScrollAlways: "Toujours",
     autoScrollNearBottom: "Près du bas",
diff --git a/ui/src/i18n/locales/hi.ts b/ui/src/i18n/locales/hi.ts
index d343462058dc..b92c80c0405e 100644
--- a/ui/src/i18n/locales/hi.ts
+++ b/ui/src/i18n/locales/hi.ts
@@ -1315,6 +1315,8 @@ export const hi: TranslationMap = {
     settings: "चैट सेटिंग्स",
     thinkingToggle: "सहायक की सोच/कार्य आउटपुट टॉगल करें",
     toolCallsToggle: "टूल कॉल और टूल परिणाम टॉगल करें",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "ऑटो-स्क्रॉल मोड",
     autoScrollAlways: "हमेशा",
     autoScrollNearBottom: "नीचे के पास",
diff --git a/ui/src/i18n/locales/id.ts b/ui/src/i18n/locales/id.ts
index 1d6dba68d66b..2de250328792 100644
--- a/ui/src/i18n/locales/id.ts
+++ b/ui/src/i18n/locales/id.ts
@@ -1329,6 +1329,8 @@ export const id: TranslationMap = {
     settings: "Pengaturan chat",
     thinkingToggle: "Alihkan output berpikir/bekerja asisten",
     toolCallsToggle: "Alihkan panggilan alat dan hasil alat",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Mode gulir otomatis",
     autoScrollAlways: "Selalu",
     autoScrollNearBottom: "Dekat bagian bawah",
diff --git a/ui/src/i18n/locales/it.ts b/ui/src/i18n/locales/it.ts
index 2bca1a614ecd..8870ad627b84 100644
--- a/ui/src/i18n/locales/it.ts
+++ b/ui/src/i18n/locales/it.ts
@@ -1336,6 +1336,8 @@ export const it: TranslationMap = {
     settings: "Impostazioni chat",
     thinkingToggle: "Attiva/disattiva output di pensiero/elaborazione dell'assistente",
     toolCallsToggle: "Attiva/disattiva chiamate agli strumenti e risultati strumenti",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Modalità di scorrimento automatico",
     autoScrollAlways: "Sempre",
     autoScrollNearBottom: "Vicino al fondo",
diff --git a/ui/src/i18n/locales/ja-JP.ts b/ui/src/i18n/locales/ja-JP.ts
index e4b542d04030..0283d1fb48e9 100644
--- a/ui/src/i18n/locales/ja-JP.ts
+++ b/ui/src/i18n/locales/ja-JP.ts
@@ -1334,6 +1334,8 @@ export const ja_JP: TranslationMap = {
     settings: "チャット設定",
     thinkingToggle: "アシスタントの思考 / 作業出力の表示を切り替え",
     toolCallsToggle: "ツール呼び出しとツール結果の表示を切り替え",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "自動スクロールモード",
     autoScrollAlways: "常に",
     autoScrollNearBottom: "下部付近",
diff --git a/ui/src/i18n/locales/ko.ts b/ui/src/i18n/locales/ko.ts
index c6b3ac125841..f29e2c381a28 100644
--- a/ui/src/i18n/locales/ko.ts
+++ b/ui/src/i18n/locales/ko.ts
@@ -1320,6 +1320,8 @@ export const ko: TranslationMap = {
     settings: "채팅 설정",
     thinkingToggle: "어시스턴트 생각/작업 출력 전환",
     toolCallsToggle: "도구 호출 및 도구 결과 전환",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "자동 스크롤 모드",
     autoScrollAlways: "항상",
     autoScrollNearBottom: "하단 근처",
diff --git a/ui/src/i18n/locales/nl.ts b/ui/src/i18n/locales/nl.ts
index e891e527b536..6c2153fdf452 100644
--- a/ui/src/i18n/locales/nl.ts
+++ b/ui/src/i18n/locales/nl.ts
@@ -1335,6 +1335,8 @@ export const nl: TranslationMap = {
     settings: "Chatinstellingen",
     thinkingToggle: "Denken-/werken-output van assistent schakelen",
     toolCallsToggle: "Tool-aanroepen en toolresultaten schakelen",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Automatisch scrollen",
     autoScrollAlways: "Altijd",
     autoScrollNearBottom: "Bijna onderaan",
diff --git a/ui/src/i18n/locales/pl.ts b/ui/src/i18n/locales/pl.ts
index b1fe1fbca153..cbbd105d17e6 100644
--- a/ui/src/i18n/locales/pl.ts
+++ b/ui/src/i18n/locales/pl.ts
@@ -1334,6 +1334,8 @@ export const pl: TranslationMap = {
     settings: "Ustawienia czatu",
     thinkingToggle: "Przełącz wyświetlanie myślenia/pracy asystenta",
     toolCallsToggle: "Przełącz wyświetlanie wywołań narzędzi i wyników narzędzi",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Tryb automatycznego przewijania",
     autoScrollAlways: "Zawsze",
     autoScrollNearBottom: "Blisko dołu",
diff --git a/ui/src/i18n/locales/pt-BR.ts b/ui/src/i18n/locales/pt-BR.ts
index 90afafc70b9c..10014ecf6fb0 100644
--- a/ui/src/i18n/locales/pt-BR.ts
+++ b/ui/src/i18n/locales/pt-BR.ts
@@ -1331,6 +1331,8 @@ export const pt_BR: TranslationMap = {
     settings: "Configurações do chat",
     thinkingToggle: "Alternar saída de pensamento/trabalho do assistente",
     toolCallsToggle: "Alternar chamadas de ferramenta e resultados de ferramenta",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Modo de rolagem automática",
     autoScrollAlways: "Sempre",
     autoScrollNearBottom: "Próximo ao final",
diff --git a/ui/src/i18n/locales/ru.ts b/ui/src/i18n/locales/ru.ts
index 75607097e092..23faa28bac2a 100644
--- a/ui/src/i18n/locales/ru.ts
+++ b/ui/src/i18n/locales/ru.ts
@@ -1339,6 +1339,8 @@ export const ru: TranslationMap = {
     settings: "Настройки чата",
     thinkingToggle: "Показать или скрыть вывод размышлений/работы ассистента",
     toolCallsToggle: "Показать или скрыть вызовы инструментов и их результаты",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Режим автопрокрутки",
     autoScrollAlways: "Всегда",
     autoScrollNearBottom: "Рядом с нижним краем",
diff --git a/ui/src/i18n/locales/th.ts b/ui/src/i18n/locales/th.ts
index b338d3ac1cb6..1ad521ac250c 100644
--- a/ui/src/i18n/locales/th.ts
+++ b/ui/src/i18n/locales/th.ts
@@ -1297,6 +1297,8 @@ export const th: TranslationMap = {
     settings: "การตั้งค่าแชท",
     thinkingToggle: "สลับการแสดงผลการคิด/การทำงานของผู้ช่วย",
     toolCallsToggle: "สลับการแสดงการเรียกใช้ tool และผลลัพธ์ของ tool",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "โหมดเลื่อนอัตโนมัติ",
     autoScrollAlways: "เสมอ",
     autoScrollNearBottom: "ใกล้ด้านล่าง",
diff --git a/ui/src/i18n/locales/tr.ts b/ui/src/i18n/locales/tr.ts
index 4e2bb6816e43..a60e34d533dd 100644
--- a/ui/src/i18n/locales/tr.ts
+++ b/ui/src/i18n/locales/tr.ts
@@ -1335,6 +1335,8 @@ export const tr: TranslationMap = {
     settings: "Sohbet ayarları",
     thinkingToggle: "Asistanın düşünme/çalışma çıktısını aç/kapat",
     toolCallsToggle: "Araç çağrılarını ve araç sonuçlarını aç/kapat",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Otomatik kaydırma modu",
     autoScrollAlways: "Her zaman",
     autoScrollNearBottom: "Alta yakın",
diff --git a/ui/src/i18n/locales/uk.ts b/ui/src/i18n/locales/uk.ts
index 3a793aee6a24..739c2bc7c148 100644
--- a/ui/src/i18n/locales/uk.ts
+++ b/ui/src/i18n/locales/uk.ts
@@ -1333,6 +1333,8 @@ export const uk: TranslationMap = {
     settings: "Налаштування чату",
     thinkingToggle: "Перемкнути показ мислення/роботи асистента",
     toolCallsToggle: "Перемкнути виклики інструментів і результати інструментів",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Режим автопрокручування",
     autoScrollAlways: "Завжди",
     autoScrollNearBottom: "Біля низу",
diff --git a/ui/src/i18n/locales/vi.ts b/ui/src/i18n/locales/vi.ts
index 381fcc34121d..96883c6ecfa0 100644
--- a/ui/src/i18n/locales/vi.ts
+++ b/ui/src/i18n/locales/vi.ts
@@ -1321,6 +1321,8 @@ export const vi: TranslationMap = {
     settings: "Cài đặt trò chuyện",
     thinkingToggle: "Bật/tắt đầu ra suy nghĩ/đang xử lý của trợ lý",
     toolCallsToggle: "Bật/tắt lượt gọi công cụ và kết quả công cụ",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "Chế độ tự động cuộn",
     autoScrollAlways: "Luôn luôn",
     autoScrollNearBottom: "Gần cuối",
diff --git a/ui/src/i18n/locales/zh-CN.ts b/ui/src/i18n/locales/zh-CN.ts
index bf53ddd3494e..18289ef30247 100644
--- a/ui/src/i18n/locales/zh-CN.ts
+++ b/ui/src/i18n/locales/zh-CN.ts
@@ -1292,6 +1292,8 @@ export const zh_CN: TranslationMap = {
     settings: "聊天设置",
     thinkingToggle: "切换助手思考/工作输出",
     toolCallsToggle: "切换工具调用和工具结果",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "自动滚动模式",
     autoScrollAlways: "始终",
     autoScrollNearBottom: "接近底部",
diff --git a/ui/src/i18n/locales/zh-TW.ts b/ui/src/i18n/locales/zh-TW.ts
index e227e5fbbfab..3246de02ee9a 100644
--- a/ui/src/i18n/locales/zh-TW.ts
+++ b/ui/src/i18n/locales/zh-TW.ts
@@ -1294,6 +1294,8 @@ export const zh_TW: TranslationMap = {
     settings: "聊天設定",
     thinkingToggle: "切換助手思考/工作輸出",
     toolCallsToggle: "切換工具呼叫與工具結果",
+    commentaryToggle: "Keep commentary after the final answer (off: clears with the final message)",
+    commentaryLabel: "Commentary",
     autoScrollMode: "自動捲動模式",
     autoScrollAlways: "一律",
     autoScrollNearBottom: "接近底部",
diff --git a/ui/src/ui/app-render.helpers.browser.test.ts b/ui/src/ui/app-render.helpers.browser.test.ts
index 0095393f8160..4469075d6a1f 100644
--- a/ui/src/ui/app-render.helpers.browser.test.ts
+++ b/ui/src/ui/app-render.helpers.browser.test.ts
@@ -119,7 +119,7 @@ describe("chat header controls (browser)", () => {
       ),
     );
 
-    expect(buttons).toHaveLength(5);
+    expect(buttons).toHaveLength(6);
 
     const labels = buttons.map((button) => button.getAttribute("data-tooltip"));
     expect(labels).toEqual([
@@ -127,6 +127,7 @@ describe("chat header controls (browser)", () => {
       `${t("chat.autoScrollMode")}: ${t("chat.autoScrollNearBottom")}`,
       t("chat.thinkingToggle"),
       t("chat.toolCallsToggle"),
+      t("chat.commentaryToggle"),
       t("chat.showCronSessions"),
     ]);
 
@@ -231,7 +232,7 @@ describe("chat header controls (browser)", () => {
       container.querySelectorAll<HTMLButtonElement>(".chat-controls__thinking .btn--icon"),
     );
 
-    expect(buttons).toHaveLength(4);
+    expect(buttons).toHaveLength(5);
     const autoScrollButton = requireButton(buttons.at(0), "auto-scroll mode");
     expect(autoScrollButton.dataset.chatAutoScrollMode).toBe("near-bottom");
     const cronButton = requireButton(buttons.at(-1), "cron sessions");
diff --git a/ui/src/ui/app-render.helpers.ts b/ui/src/ui/app-render.helpers.ts
index 481cb015791c..c45d91320c6c 100644
--- a/ui/src/ui/app-render.helpers.ts
+++ b/ui/src/ui/app-render.helpers.ts
@@ -365,12 +365,16 @@ export function renderChatControls(state: AppViewState) {
   const disableThinkingToggle = state.onboarding;
   const showThinking = state.onboarding ? false : state.settings.chatShowThinking;
   const showToolCalls = state.onboarding ? true : state.settings.chatShowToolCalls;
+  const persistCommentary = state.settings.chatPersistCommentary !== false;
   const thinkingLabel = disableThinkingToggle
     ? t("chat.onboardingDisabled")
     : t("chat.thinkingToggle");
   const toolCallsLabel = disableThinkingToggle
     ? t("chat.onboardingDisabled")
     : t("chat.toolCallsToggle");
+  const commentaryLabel = disableThinkingToggle
+    ? t("chat.onboardingDisabled")
+    : t("chat.commentaryToggle");
   const refreshDisabled =
     !state.connected ||
     state.chatManualRefreshInFlight ||
@@ -503,6 +507,28 @@ export function renderChatControls(state: AppViewState) {
               ${toolCallsIcon}
               <span class="chat-settings-action__text">${t("agents.tabs.tools")}</span>
             </button>
+            <button
+              class="btn btn--sm btn--icon chat-settings-action ${persistCommentary
+                ? "active"
+                : ""}"
+              ?disabled=${disableThinkingToggle}
+              @click=${() => {
+                if (disableThinkingToggle) {
+                  return;
+                }
+                state.applySettings({
+                  ...state.settings,
+                  chatPersistCommentary: !persistCommentary,
+                });
+              }}
+              aria-pressed=${persistCommentary}
+              title=${commentaryLabel}
+              aria-label=${commentaryLabel}
+              data-tooltip=${commentaryLabel}
+            >
+              ${persistCommentary ? icons.pin : icons.pinOff}
+              <span class="chat-settings-action__text">${t("chat.commentaryLabel")}</span>
+            </button>
             <button
               class="btn btn--sm btn--icon chat-settings-action ${hideCron ? "active" : ""}"
               @click=${() => {
@@ -534,6 +560,7 @@ export function renderChatMobileToggle(state: AppViewState) {
   const disableThinkingToggle = state.onboarding;
   const showThinking = state.onboarding ? false : state.settings.chatShowThinking;
   const showToolCalls = state.onboarding ? true : state.settings.chatShowToolCalls;
+  const persistCommentary = state.settings.chatPersistCommentary !== false;
   const hideCron = state.sessionsHideCron ?? true;
   const hiddenCronCount = hideCron ? countHiddenCronSessions(state, state.sessionsResult) : 0;
   const toolCallsIcon = html`
@@ -627,6 +654,22 @@ export function renderChatMobileToggle(state: AppViewState) {
             >
               ${toolCallsIcon}
             </button>
+            <button
+              class="btn btn--sm btn--icon ${persistCommentary ? "active" : ""}"
+              ?disabled=${disableThinkingToggle}
+              @click=${() => {
+                if (!disableThinkingToggle) {
+                  state.applySettings({
+                    ...state.settings,
+                    chatPersistCommentary: !persistCommentary,
+                  });
+                }
+              }}
+              aria-pressed=${persistCommentary}
+              title=${t("chat.commentaryToggle")}
+            >
+              ${persistCommentary ? icons.pin : icons.pinOff}
+            </button>
             <button
               class="btn btn--sm btn--icon ${hideCron ? "active" : ""}"
               @click=${() => {
diff --git a/ui/src/ui/chat/stream-reconciliation.test.ts b/ui/src/ui/chat/stream-reconciliation.test.ts
index 15a6cd85490f..9628bf296fb0 100644
--- a/ui/src/ui/chat/stream-reconciliation.test.ts
+++ b/ui/src/ui/chat/stream-reconciliation.test.ts
@@ -183,6 +183,72 @@ describe("stream reconciliation", () => {
     expect(next.map(messageText)).toEqual(["latest ask", "before tool\nfinal answer"]);
   });
 
+  it("omits keyed commentary parts when persistCommentary is false (transient mode)", () => {
+    const state = {
+      chatStream: null,
+      chatStreamStartedAt: null,
+      chatStreamSegments: [
+        { text: "first preamble", ts: 2, itemId: "preamble-1" },
+        { text: "second preamble", ts: 3, itemId: "preamble-2" },
+      ],
+    } satisfies StreamReconciliationState & {
+      chatStreamSegments: Array<{ text: string; ts: number; itemId: string }>;
+    };
+    const messages = [
+      { role: "user", content: "latest ask", timestamp: 1 },
+      { role: "assistant", content: [{ type: "text", text: "final reply" }], timestamp: 4 },
+    ];
+
+    const next = materializeVisibleStreamState(messages, state, {
+      ...visibleStreamOptions,
+      persistCommentary: false,
+    });
+
+    // Keyed commentary stays live during streaming but is never materialized,
+    // so only the user ask and the final reply remain.
+    expect(next.map(messageText)).toEqual(["latest ask", "final reply"]);
+  });
+
+  it("still materializes the current stream tail when persistCommentary is false", () => {
+    const state = {
+      chatStream: "draft answer",
+      chatStreamStartedAt: 3,
+      chatStreamSegments: [{ text: "transient preamble", ts: 2, itemId: "preamble-1" }],
+    } satisfies StreamReconciliationState & {
+      chatStreamSegments: Array<{ text: string; ts: number; itemId: string }>;
+    };
+    const messages = [{ role: "user", content: "latest ask", timestamp: 1 }];
+
+    const next = materializeVisibleStreamState(messages, state, {
+      ...visibleStreamOptions,
+      persistCommentary: false,
+    });
+
+    // The keyed preamble is dropped, but the non-keyed current draft is preserved.
+    expect(next.map(messageText)).toEqual(["latest ask", "draft answer"]);
+  });
+
+  it("materializes keyed commentary parts when persistCommentary is true (persist mode)", () => {
+    const state = {
+      chatStream: null,
+      chatStreamStartedAt: null,
+      chatStreamSegments: [{ text: "kept preamble", ts: 2, itemId: "preamble-1" }],
+    } satisfies StreamReconciliationState & {
+      chatStreamSegments: Array<{ text: string; ts: number; itemId: string }>;
+    };
+    const messages = [
+      { role: "user", content: "latest ask", timestamp: 1 },
+      { role: "assistant", content: [{ type: "text", text: "final reply" }], timestamp: 4 },
+    ];
+
+    const next = materializeVisibleStreamState(messages, state, {
+      ...visibleStreamOptions,
+      persistCommentary: true,
+    });
+
+    expect(next.map(messageText)).toEqual(["latest ask", "kept preamble", "final reply"]);
+  });
+
   it("replaces current-stream fallbacks with matching terminal messages", () => {
     const state = {
       chatStream: "draft answer",
diff --git a/ui/src/ui/chat/stream-reconciliation.ts b/ui/src/ui/chat/stream-reconciliation.ts
index d3a07c3eec85..7d71a817f51f 100644
--- a/ui/src/ui/chat/stream-reconciliation.ts
+++ b/ui/src/ui/chat/stream-reconciliation.ts
@@ -42,6 +42,10 @@ export type MaterializeVisibleStreamOptions = {
   includeCurrent?: boolean;
   requirePersistedTool?: boolean;
   replacementMessages?: unknown[];
+  // When false, keyed commentary/preamble parts are not materialized into the
+  // persistent message list, so they clear with the final answer (transient mode).
+  // Defaults to true (persist commentary).
+  persistCommentary?: boolean;
   isHiddenAssistantMessage: AssistantMessageVisibility;
   isHiddenStreamText: StreamVisibility;
 };
@@ -450,7 +454,13 @@ export function materializeVisibleStreamState(
   opts: MaterializeVisibleStreamOptions,
 ): unknown[] {
   let nextMessages = messages;
+  const persistCommentary = opts.persistCommentary !== false;
   for (const part of visibleAssistantStreamParts(state, opts)) {
+    // Transient mode: keyed commentary stays live during streaming but is never
+    // materialized, so it disappears once the final message lands.
+    if (!persistCommentary && part.itemId) {
+      continue;
+    }
     const replacementMessages = opts.replacementMessages ?? [];
     if (
       hasAssistantStreamPartReplacement(
diff --git a/ui/src/ui/controllers/chat.test.ts b/ui/src/ui/controllers/chat.test.ts
index 6ae76fffd171..2f89bcaca53f 100644
--- a/ui/src/ui/controllers/chat.test.ts
+++ b/ui/src/ui/controllers/chat.test.ts
@@ -583,6 +583,68 @@ describe("handleChatEvent", () => {
     expect(state.chatStreamStartedAt).toBe(null);
   });
 
+  it("persists keyed commentary alongside the final answer by default", () => {
+    const user = { role: "user", content: [{ type: "text", text: "Ask" }], timestamp: 1 };
+    const state = createState({
+      sessionKey: "main",
+      chatRunId: "run-1",
+      chatMessages: [user],
+      chatStream: null,
+      chatStreamStartedAt: null,
+    }) as ChatState & {
+      chatStreamSegments: Array<{ text: string; ts: number; itemId: string }>;
+    };
+    state.chatStreamSegments = [{ text: "Looking into it.", ts: 2, itemId: "preamble-1" }];
+    const payload: ChatEventPayload = {
+      runId: "run-1",
+      sessionKey: "main",
+      state: "final",
+      message: {
+        role: "assistant",
+        content: [{ type: "text", text: "Final answer." }],
+        timestamp: 5,
+      },
+    };
+
+    expect(handleChatEvent(state, payload)).toBe("final");
+    expect(state.chatMessages).toHaveLength(3);
+    expectTextChatMessage(state.chatMessages[0], "user", "Ask");
+    expectTextChatMessage(state.chatMessages[1], "assistant", "Looking into it.");
+    expectTextChatMessage(state.chatMessages[2], "assistant", "Final answer.");
+    expect(state.chatStreamSegments).toEqual([]);
+  });
+
+  it("clears keyed commentary with the final answer when chatPersistCommentary is false", () => {
+    const user = { role: "user", content: [{ type: "text", text: "Ask" }], timestamp: 1 };
+    const state = createState({
+      sessionKey: "main",
+      chatRunId: "run-1",
+      chatMessages: [user],
+      chatStream: null,
+      chatStreamStartedAt: null,
+      settings: { chatPersistCommentary: false },
+    }) as ChatState & {
+      chatStreamSegments: Array<{ text: string; ts: number; itemId: string }>;
+    };
+    state.chatStreamSegments = [{ text: "Looking into it.", ts: 2, itemId: "preamble-1" }];
+    const payload: ChatEventPayload = {
+      runId: "run-1",
+      sessionKey: "main",
+      state: "final",
+      message: {
+        role: "assistant",
+        content: [{ type: "text", text: "Final answer." }],
+        timestamp: 5,
+      },
+    };
+
+    expect(handleChatEvent(state, payload)).toBe("final");
+    expect(state.chatMessages).toHaveLength(2);
+    expectTextChatMessage(state.chatMessages[0], "user", "Ask");
+    expectTextChatMessage(state.chatMessages[1], "assistant", "Final answer.");
+    expect(state.chatStreamSegments).toEqual([]);
+  });
+
   it("reconciles cached run and indicator state on terminal events", () => {
     vi.useFakeTimers();
     try {
diff --git a/ui/src/ui/controllers/chat.ts b/ui/src/ui/controllers/chat.ts
index f1f669652b3a..ad09fab9bf81 100644
--- a/ui/src/ui/controllers/chat.ts
+++ b/ui/src/ui/controllers/chat.ts
@@ -204,11 +204,17 @@ function materializeVisibleAssistantStreamMessages(
 ): unknown[] {
   return materializeVisibleStreamState(messages, state, {
     ...opts,
+    persistCommentary: chatPersistCommentaryEnabled(state),
     isHiddenAssistantMessage: shouldHideAssistantChatMessage,
     isHiddenStreamText: isHiddenAssistantStreamText,
   });
 }
 
+function chatPersistCommentaryEnabled(state: ChatState): boolean {
+  // Per-viewer display preference; defaults to persist when unset (e.g. tests/headless).
+  return state.settings?.chatPersistCommentary !== false;
+}
+
 function hasTranscriptMeta(message: unknown): boolean {
   return Boolean(
     message &&
@@ -405,6 +411,8 @@ export type ChatState = {
   agentsList?: ChatAgentsListSnapshot | null;
   agentsSelectedId?: string | null;
   hello?: GatewayHelloOk | null;
+  // Narrow view of UiSettings; the runtime host is the full app component.
+  settings?: { chatPersistCommentary?: boolean };
 };
 
 type ChatAgentsListSnapshot = Partial<Omit<AgentsListResult, "agents">> & {
diff --git a/ui/src/ui/storage.node.test.ts b/ui/src/ui/storage.node.test.ts
index 17c35edda3a9..87e4c2bab1fa 100644
--- a/ui/src/ui/storage.node.test.ts
+++ b/ui/src/ui/storage.node.test.ts
@@ -140,6 +140,7 @@ describe("loadSettings default gateway URL derivation", () => {
       themeMode: "system",
       chatShowThinking: true,
       chatShowToolCalls: true,
+      chatPersistCommentary: true,
       chatAutoScroll: "near-bottom",
       splitRatio: 0.6,
       navCollapsed: false,
@@ -271,6 +272,7 @@ describe("loadSettings default gateway URL derivation", () => {
       themeMode: "system",
       chatShowThinking: true,
       chatShowToolCalls: true,
+      chatPersistCommentary: true,
       chatAutoScroll: "near-bottom",
       splitRatio: 0.6,
       navCollapsed: false,
diff --git a/ui/src/ui/storage.ts b/ui/src/ui/storage.ts
index 042fc0b00b63..cc2736cf71df 100644
--- a/ui/src/ui/storage.ts
+++ b/ui/src/ui/storage.ts
@@ -88,6 +88,9 @@ export type UiSettings = {
   themeMode: ThemeMode;
   chatShowThinking: boolean;
   chatShowToolCalls: boolean;
+  // Keep streamed commentary/preamble blocks visible after the final answer (default true).
+  // When false, commentary clears as the final message arrives (transient progress).
+  chatPersistCommentary?: boolean;
   chatAutoScroll?: ChatAutoScrollMode;
   splitRatio: number; // Sidebar split ratio (0.4 to 0.7, default 0.6)
   navCollapsed: boolean; // Collapsible sidebar state
@@ -246,6 +249,7 @@ export function loadSettings(): UiSettings {
     themeMode: "system",
     chatShowThinking: true,
     chatShowToolCalls: true,
+    chatPersistCommentary: true,
     chatAutoScroll: "near-bottom",
     splitRatio: 0.6,
     navCollapsed: false,
@@ -291,6 +295,10 @@ export function loadSettings(): UiSettings {
         typeof parsed.chatShowToolCalls === "boolean"
           ? parsed.chatShowToolCalls
           : defaults.chatShowToolCalls,
+      chatPersistCommentary:
+        typeof parsed.chatPersistCommentary === "boolean"
+          ? parsed.chatPersistCommentary
+          : defaults.chatPersistCommentary,
       chatAutoScroll: normalizeChatAutoScrollMode(parsed.chatAutoScroll),
       splitRatio:
         typeof parsed.splitRatio === "number" &&
@@ -490,6 +498,7 @@ function persistSettings(next: UiSettings) {
     themeMode: next.themeMode,
     chatShowThinking: next.chatShowThinking,
     chatShowToolCalls: next.chatShowToolCalls,
+    chatPersistCommentary: next.chatPersistCommentary ?? true,
     chatAutoScroll: normalizeChatAutoScrollMode(next.chatAutoScroll),
     splitRatio: next.splitRatio,
     navCollapsed: next.navCollapsed,