diff --git a/src/api/client.ts b/src/api/client.ts
index 2de6f0b..ab987ee 100644
--- a/src/api/client.ts
+++ b/src/api/client.ts
@@ -60,7 +60,7 @@ export class ApiError extends Error {
     code?: string,
     details?: InsufficientBalanceDetails | Record<string, unknown>,
   ) {
-    super(message);
+    super(sanitizeUserFacingErrorMessage(message));
     this.name = 'ApiError';
     this.status = status;
     this.code = code;
@@ -68,6 +68,21 @@ export class ApiError extends Error {
   }
 }
 
+function sanitizeUserFacingErrorMessage(message: string) {
+  const normalized = String(message ?? '').trim();
+  if (!normalized) return normalized;
+  if (!/goose|goosed/i.test(normalized)) return normalized;
+  if (/超时|timeout/i.test(normalized)) {
+    return '后端连接超时，请确认后端服务正常后重试';
+  }
+  if (/不可用|连接失败|failed to fetch|networkerror|fetch failed|upstream|econn|enotfound/i.test(normalized)) {
+    return '后端连接失败，请稍后重试';
+  }
+  return normalized
+    .replace(/\bgoosed\b/gi, '后端服务')
+    .replace(/\bgoose\b/gi, '后端');
+}
+
 async function parseErrorResponse(res: Response): Promise<{
   message: string;
   code?: string;
@@ -95,7 +110,7 @@ async function parseErrorResponse(res: Response): Promise<{
     const details = nested.details ?? body.details;
     if (code === 'INSUFFICIENT_BALANCE') {
       return {
-        message,
+        message: sanitizeUserFacingErrorMessage(message),
         code,
         details: {
           code: 'INSUFFICIENT_BALANCE' as const,
@@ -112,14 +127,14 @@ async function parseErrorResponse(res: Response): Promise<{
       };
     }
     return {
-      message,
+      message: sanitizeUserFacingErrorMessage(message),
       code,
       details: details && typeof details === 'object'
         ? (details as InsufficientBalanceDetails | Record<string, unknown>)
         : undefined,
     };
   } catch {
-    return { message: text || res.statusText };
+    return { message: sanitizeUserFacingErrorMessage(text || res.statusText) };
   }
 }
 
@@ -200,12 +215,17 @@ async function portalFetch<T>(path: string, init?: RequestInit): Promise<T> {
 function formatNetworkError(err: unknown) {
   const message = err instanceof Error ? err.message : '网络请求失败';
   if (err instanceof DOMException && err.name === 'AbortError') {
-    return '连接 goose 服务超时，请确认 goosed/H5 后端正在运行后重试';
+    return '后端连接超时，请确认后端服务正常后重试';
   }
   if (message.includes('Failed to fetch') || message.includes('NetworkError')) {
     return '无法连接后端服务，请先运行: pnpm dev 或 node server.mjs';
   }
-  return message;
+  return sanitizeUserFacingErrorMessage(message);
+}
+
+function sanitizeSessionEvent(event: SessionEvent): SessionEvent {
+  if (event.type !== 'Error') return event;
+  return { ...event, error: sanitizeUserFacingErrorMessage(event.error) };
 }
 
 async function apiFetch<T>(path: string, init?: RequestInit): Promise<T> {
@@ -1921,7 +1941,7 @@ export function subscribeSessionEvents(
                 }
                 continue;
               }
-              onEvent(JSON.parse(data) as SessionEvent);
+              onEvent(sanitizeSessionEvent(JSON.parse(data) as SessionEvent));
             } catch {
               // ignore malformed frames
             }
diff --git a/tkmind-proxy.mjs b/tkmind-proxy.mjs
index 531890e..9d33e88 100644
--- a/tkmind-proxy.mjs
+++ b/tkmind-proxy.mjs
@@ -14,6 +14,21 @@ function isHttpsTarget(target) {
   return target.startsWith('https://');
 }
 
+function sanitizeUserFacingProxyMessage(message, fallback = '后端连接失败，请稍后重试') {
+  const normalized = String(message ?? '').trim();
+  if (!normalized) return fallback;
+  if (!/goose|goosed/i.test(normalized)) return normalized;
+  if (/超时|timeout/i.test(normalized)) {
+    return '后端连接超时，请确认后端服务正常后重试';
+  }
+  if (/不可用|连接失败|failed to fetch|networkerror|fetch failed|upstream|econn|enotfound/i.test(normalized)) {
+    return fallback;
+  }
+  return normalized
+    .replace(/\bgoosed\b/gi, '后端服务')
+    .replace(/\bgoose\b/gi, '后端');
+}
+
 async function apiFetch(target, apiSecret, pathname, init = {}) {
   const url = new URL(pathname, target);
   const headers = {
@@ -308,7 +323,12 @@ export function createTkmindProxy({ apiTarget, apiTargets, apiSecret, userAuth,
 
           res.status(upstream.status).json(payload);
         } catch (err) {
-          res.status(500).json({ message: err instanceof Error ? err.message : '恢复会话失败' });
+          res.status(500).json({
+            message: sanitizeUserFacingProxyMessage(
+              err instanceof Error ? err.message : '恢复会话失败',
+              '恢复会话失败',
+            ),
+          });
         }
       },
     ],
@@ -339,12 +359,15 @@ export function createTkmindProxy({ apiTarget, apiTargets, apiSecret, userAuth,
                 if (owned.has(item.id)) sessionsById.set(item.id, item);
               }
             } catch (err) {
-              lastFailure = err instanceof Error ? err.message : '读取会话失败';
+              lastFailure = sanitizeUserFacingProxyMessage(
+                err instanceof Error ? err.message : '读取会话失败',
+                '读取会话失败',
+              );
             }
           }
 
           if (healthyTargets === 0) {
-            res.status(502).json({ message: lastFailure ?? '所有 goose 服务不可用' });
+            res.status(502).json({ message: lastFailure ?? '后端连接失败，请稍后重试' });
             return;
           }
           if (healthyTargets < targets.length) {
@@ -352,7 +375,12 @@ export function createTkmindProxy({ apiTarget, apiTargets, apiSecret, userAuth,
           }
           res.json({ sessions: [...sessionsById.values()] });
         } catch (err) {
-          res.status(500).json({ message: err instanceof Error ? err.message : '读取会话失败' });
+          res.status(500).json({
+            message: sanitizeUserFacingProxyMessage(
+              err instanceof Error ? err.message : '读取会话失败',
+              '读取会话失败',
+            ),
+          });
         }
       },
     ],
@@ -377,7 +405,12 @@ export function createTkmindProxy({ apiTarget, apiTargets, apiSecret, userAuth,
         req.agentSessionId = sessionId;
         await build(req, res, next);
       } catch (err) {
-        res.status(500).json({ message: err instanceof Error ? err.message : '请求失败' });
+        res.status(500).json({
+          message: sanitizeUserFacingProxyMessage(
+            err instanceof Error ? err.message : '请求失败',
+            '请求失败',
+          ),
+        });
       }
     },
   ];
@@ -441,7 +474,12 @@ export function createTkmindProxy({ apiTarget, apiTargets, apiSecret, userAuth,
       source.on('error', () => res.end());
       source.pipe(billingTransform);
     } catch (err) {
-      res.status(502).json({ message: err instanceof Error ? err.message : 'SSE 代理失败' });
+      res.status(502).json({
+        message: sanitizeUserFacingProxyMessage(
+          err instanceof Error ? err.message : 'SSE 代理失败',
+          'SSE 代理失败',
+        ),
+      });
     }
   };
 
@@ -494,7 +532,12 @@ export function createTkmindProxy({ apiTarget, apiTargets, apiSecret, userAuth,
 
       sendProxyResponse(res, upstream);
     } catch (err) {
-      res.status(502).json({ message: err instanceof Error ? err.message : '代理失败' });
+      res.status(502).json({
+        message: sanitizeUserFacingProxyMessage(
+          err instanceof Error ? err.message : '代理失败',
+          '代理失败',
+        ),
+      });
     }
   };