diff --git a/desktop/src/components/chat/MessageList.test.tsx b/desktop/src/components/chat/MessageList.test.tsx
index 127d958b..c5292da7 100644
--- a/desktop/src/components/chat/MessageList.test.tsx
+++ b/desktop/src/components/chat/MessageList.test.tsx
@@ -7942,6 +7942,43 @@ describe('MessageList nested tool calls', () => {
     expect(screen.queryByText(/This model does not support images/)).toBeNull()
   })
 
+  it.each([
+    ['en', /too large for your provider or relay/, /removed automatically/],
+    ['zh', /服务商或中转站允许的大小/, /自动移除/],
+  ] as const)(
+    'explains a request-too-large rejection as a provider limit and the recovery that follows (%s)',
+    (locale, limit, recovery) => {
+      useSettingsStore.setState({ locale })
+      useChatStore.setState({
+        sessions: {
+          [ACTIVE_TAB]: makeSessionState({
+            messages: [
+              {
+                id: 'error-1',
+                type: 'error',
+                code: 'invalid_request',
+                businessErrorCode: 'request_too_large',
+                message:
+                  'Request too large: your provider or relay rejected it (HTTP 413). This conversation is about 24MB.',
+                timestamp: 1,
+              },
+            ],
+          }),
+        },
+      })
+
+      render(<MessageList />)
+
+      expect(screen.getByText(limit)).toBeTruthy()
+      expect(screen.getByText(recovery)).toBeTruthy()
+      // The old copy blamed the selected model and asked users to delete files
+      // by hand, although the limit belongs to the provider and old media is
+      // now dropped automatically.
+      expect(screen.queryByText(/selected model|当前模型/)).toBeNull()
+      expect(screen.queryByText(/Remove large files|移除大文件/)).toBeNull()
+    },
+  )
+
   it('restores opener focus without scrolling when its render item remains fully visible', async () => {
     useChatStore.setState({
       sessions: {
diff --git a/desktop/src/i18n/locales/en.ts b/desktop/src/i18n/locales/en.ts
index cf625384..c9f2ed1d 100644
--- a/desktop/src/i18n/locales/en.ts
+++ b/desktop/src/i18n/locales/en.ts
@@ -3622,7 +3622,7 @@ Row 9, all 8 cells: continuing from straight down, turning left through lower-le
   'businessError.pdf_invalid': 'The PDF file is not valid. Convert it to text or send a different file.',
   'businessError.image_too_large': 'The image is too large for the selected model. Resize it or send a smaller image.',
   'businessError.image_unsupported': 'This model does not support images. Continue with text, or switch to a vision-capable model and send the image again.',
-  'businessError.request_too_large': 'The request is too large for the selected model. Remove large files or retry with a smaller message.',
+  'businessError.request_too_large': 'The request is too large for your provider or relay. Earlier images and documents are removed automatically on your next message; if it still fails, compact the conversation or start a new session.',
   'businessError.prompt_too_long': 'The prompt is too long for the selected model. Compact the conversation or retry with less context.',
   'businessError.auto_mode_unavailable': 'Auto mode is unavailable for your current plan.',
 
diff --git a/desktop/src/i18n/locales/jp.ts b/desktop/src/i18n/locales/jp.ts
index 1fb4f81e..54052c22 100644
--- a/desktop/src/i18n/locales/jp.ts
+++ b/desktop/src/i18n/locales/jp.ts
@@ -3623,7 +3623,7 @@ export const jp: Record<TranslationKey, string> = {
   'businessError.pdf_invalid': 'PDF ファイルが無効です。テキストに変換するか、別のファイルを送信してください。',
   'businessError.image_too_large': '画像が選択したモデルには大きすぎます。サイズを変更するか、より小さい画像を送信してください。',
   'businessError.image_unsupported': 'このモデルは画像をサポートしていません。テキストで続行するか、ビジョン対応モデルに切り替えて画像を再送信してください。',
-  'businessError.request_too_large': 'リクエストが選択したモデルには大きすぎます。大きなファイルを削除するか、より短いメッセージで再試行してください。',
+  'businessError.request_too_large': 'リクエストがプロバイダーまたは中継サービスの許容サイズを超えました。次のメッセージで以前の画像とドキュメントが自動的に削除されます。それでも失敗する場合は、会話を圧縮するか、新しいセッションを開始してください。',
   'businessError.prompt_too_long': 'プロンプトが選択したモデルには長すぎます。会話を圧縮するか、コンテキストを減らして再試行してください。',
   'businessError.auto_mode_unavailable': '自動モードは現在のプランでは利用できません。',
 
diff --git a/desktop/src/i18n/locales/kr.ts b/desktop/src/i18n/locales/kr.ts
index 89373906..f1a0956e 100644
--- a/desktop/src/i18n/locales/kr.ts
+++ b/desktop/src/i18n/locales/kr.ts
@@ -3625,7 +3625,7 @@ export const kr: Record<TranslationKey, string> = {
   'businessError.pdf_invalid': 'PDF 파일이 유효하지 않습니다. 텍스트로 변환하거나 다른 파일을 보내세요.',
   'businessError.image_too_large': '이미지가 선택한 모델에 비해 너무 큽니다. 크기를 조정하거나 더 작은 이미지를 보내세요.',
   'businessError.image_unsupported': '이 모델은 이미지를 지원하지 않습니다. 텍스트로 계속하거나, 비전 지원 모델로 전환하여 이미지를 다시 보내세요.',
-  'businessError.request_too_large': '요청이 선택한 모델에 비해 너무 큽니다. 큰 파일을 제거하거나 더 짧은 메시지로 다시 시도하세요.',
+  'businessError.request_too_large': '요청이 공급자 또는 중계 서버가 허용하는 크기를 초과했습니다. 다음 메시지에서 이전 이미지와 문서가 자동으로 제거됩니다. 그래도 실패하면 대화를 압축하거나 새 세션을 시작하세요.',
   'businessError.prompt_too_long': '프롬프트가 선택한 모델에 비해 너무 깁니다. 대화를 압축하거나 컨텍스트를 줄여 다시 시도하세요.',
   'businessError.auto_mode_unavailable': '자동 모드는 현재 요금제에서 사용할 수 없습니다.',
 
diff --git a/desktop/src/i18n/locales/zh-TW.ts b/desktop/src/i18n/locales/zh-TW.ts
index 27831c77..36170619 100644
--- a/desktop/src/i18n/locales/zh-TW.ts
+++ b/desktop/src/i18n/locales/zh-TW.ts
@@ -3622,7 +3622,7 @@ export const zh: Record<TranslationKey, string> = {
   'businessError.pdf_invalid': '這個 PDF 檔案無效。請先轉成文字，或換一個檔案傳送。',
   'businessError.image_too_large': '這張圖片超出了當前模型可處理的大小。請壓縮圖片，或換一張更小的圖片。',
   'businessError.image_unsupported': '當前模型不支援圖片。請繼續使用文字，或切換到支援視覺的模型後重新傳送圖片。',
-  'businessError.request_too_large': '這次請求超出了當前模型可處理的大小。請移除大檔案，或縮短訊息後重試。',
+  'businessError.request_too_large': '這次請求超出了服務商或中轉站允許的大小。下一則訊息會自動移除較早的圖片和文件；如果仍然失敗，請壓縮會話或新開會話。',
   'businessError.prompt_too_long': '當前上下文超出了模型限制。請先壓縮會話，或減少上下文後重試。',
   'businessError.auto_mode_unavailable': '當前套餐不支援自動模式。',
 
diff --git a/desktop/src/i18n/locales/zh.ts b/desktop/src/i18n/locales/zh.ts
index 6cd47d2e..624a6dd0 100644
--- a/desktop/src/i18n/locales/zh.ts
+++ b/desktop/src/i18n/locales/zh.ts
@@ -3621,7 +3621,7 @@ export const zh: Record<TranslationKey, string> = {
   'businessError.pdf_invalid': '这个 PDF 文件无效。请先转成文本，或换一个文件发送。',
   'businessError.image_too_large': '这张图片超出了当前模型可处理的大小。请压缩图片，或换一张更小的图片。',
   'businessError.image_unsupported': '当前模型不支持图片。请继续使用文字，或切换到支持视觉的模型后重新发送图片。',
-  'businessError.request_too_large': '这次请求超出了当前模型可处理的大小。请移除大文件，或缩短消息后重试。',
+  'businessError.request_too_large': '这次请求超出了服务商或中转站允许的大小。下一条消息会自动移除较早的图片和文档；如果仍然失败，请压缩会话或新开会话。',
   'businessError.prompt_too_long': '当前上下文超出了模型限制。请先压缩会话，或减少上下文后重试。',
   'businessError.auto_mode_unavailable': '当前套餐不支持自动模式。',