diff --git a/docs/archives/115-ipc-serialization-fixes/architecture-evolution.md b/docs/archives/115-ipc-serialization-fixes/architecture-evolution.md
index c7aaeaa9..22a43bd5 100644
--- a/docs/archives/115-ipc-serialization-fixes/architecture-evolution.md
+++ b/docs/archives/115-ipc-serialization-fixes/architecture-evolution.md
@@ -146,3 +146,56 @@ await modelManager.addModel(key, config) // 自动序列化
 - ❌ 忽视开发体验
 
 这次架构演进是一个很好的例子，展示了如何通过合理的架构设计来解决技术问题，同时提升开发体验。
+
+## 🔄 第三阶段：代理层职责边界优化 (2025-07)
+
+### 问题发现
+在解决Vue组件类型错误时，发现了一个重要的架构问题：ElectronProxy层承担了过多的数据格式转换职责。
+
+**现象**：
+- Web版运行正常，桌面版出现`[object Object]`错误
+- InputWithSelect组件期望String类型，但接收到Object类型
+- 同样的代码在不同环境下表现不同
+
+### 根本原因分析
+1. **类型定义不一致**：`global.d.ts`中定义`fetchModelList`返回`string[]`，但实际返回`ModelOption[]`
+2. **职责边界模糊**：ElectronProxy既负责IPC通信，又处理复杂的数据格式转换
+3. **异步性放大问题**：桌面版的IPC异步性暴露了Web版中被掩盖的竞态条件
+
+**Web版 vs 桌面版的关键差异**：
+- **Web版**：同步数据流，事件循环掩盖了竞态条件
+- **桌面版**：IPC异步通信创造了race condition，使潜在问题显现
+
+### 解决方案
+1. **修复类型定义**：
+   ```typescript
+   // 修复前
+   fetchModelList: (provider: string, customConfig?: any) => Promise<string[]>;
+
+   // 修复后
+   fetchModelList: (provider: string, customConfig?: any) => Promise<Array<{value: string, label: string}>>;
+   ```
+
+2. **简化代理层**：
+   ```typescript
+   // ElectronProxy只负责IPC通信，不做数据转换
+   async fetchModelList(provider: string, customConfig?: Partial<any>): Promise<ModelOption[]> {
+     const safeCustomConfig = customConfig ? safeSerializeForIPC(customConfig) : customConfig;
+     return this.electronAPI.llm.fetchModelList(provider, safeCustomConfig);
+   }
+   ```
+
+3. **移除冗余事件**：删除不必要的`@select`事件处理，简化数据流
+
+### 架构原则确立
+- **单一职责**：每层只负责自己的核心功能，代理层专注IPC通信
+- **类型安全**：TypeScript类型定义必须与实际实现保持严格一致
+- **数据流简洁**：避免不必要的中间转换层，减少出错可能性
+
+### 经验总结
+1. **异步性是双刃剑**：它会放大架构设计中的潜在问题
+2. **类型安全的重要性**：类型定义不仅是文档，更是架构约束
+3. **职责边界要清晰**：特别是在跨进程通信的场景下
+4. **环境差异要重视**：同样的代码在不同环境下可能表现不同
+
+这次经验强化了我们对IPC架构设计的理解，为未来的跨进程功能开发提供了重要指导。
diff --git a/packages/core/src/services/llm/electron-proxy.ts b/packages/core/src/services/llm/electron-proxy.ts
index b7d5eaaa..919e7417 100644
--- a/packages/core/src/services/llm/electron-proxy.ts
+++ b/packages/core/src/services/llm/electron-proxy.ts
@@ -57,8 +57,6 @@ export class ElectronLLMProxy implements ILLMService {
   ): Promise<ModelOption[]> {
     // 自动序列化，防止Vue响应式对象IPC传递错误
     const safeCustomConfig = customConfig ? safeSerializeForIPC(customConfig) : customConfig;
-    const modelNames = await this.electronAPI.llm.fetchModelList(provider, safeCustomConfig);
-    // Convert string array to ModelOption array
-    return modelNames.map(name => ({ value: name, label: name }));
+    return this.electronAPI.llm.fetchModelList(provider, safeCustomConfig);
   }
 } 
\ No newline at end of file
diff --git a/packages/core/src/types/global.d.ts b/packages/core/src/types/global.d.ts
index 49a6b02e..b8f291f9 100644
--- a/packages/core/src/types/global.d.ts
+++ b/packages/core/src/types/global.d.ts
@@ -26,7 +26,7 @@ interface Window {
         }
       ) => Promise<void>;
       testConnection: (provider: string) => Promise<void>;
-      fetchModelList: (provider: string, customConfig?: any) => Promise<string[]>;
+      fetchModelList: (provider: string, customConfig?: any) => Promise<Array<{value: string, label: string}>>;
     };
     model: {
       getModels: () => Promise<any[]>;
diff --git a/packages/ui/src/components/ModelManager.vue b/packages/ui/src/components/ModelManager.vue
index ba75fad9..6938ae83 100644
--- a/packages/ui/src/components/ModelManager.vue
+++ b/packages/ui/src/components/ModelManager.vue
@@ -145,7 +145,6 @@
                       :hint-text="t('modelManager.clickToFetchModels')"
                       required
                       :placeholder="t('modelManager.defaultModelPlaceholder')"
-                      @select="handleModelSelect"
                       @fetch-options="handleFetchEditingModels"
                     />
                   </div>
@@ -339,7 +338,6 @@
                       :hint-text="t('modelManager.clickToFetchModels')"
                       required
                       :placeholder="t('modelManager.defaultModelPlaceholder')"
-                      @select="handleModelSelect"
                       @fetch-options="handleFetchNewModels"
                     />
                   </div>
@@ -715,7 +713,7 @@ const editModel = async (key) => {
       originalKey: key, // 保存原始key
       name: model.name,
       baseURL: model.baseURL,
-      defaultModel: model.defaultModel,
+      defaultModel: typeof model.defaultModel === 'string' ? model.defaultModel : (model.defaultModel?.value || model.defaultModel?.id || ''),
       apiKey: maskedApiKey,
       displayMaskedKey: true,
       originalApiKey: model.apiKey,
@@ -808,10 +806,7 @@ const addDefaultModelOptions = (providerKey) => {
     modelOptions.value = [];
   }
 };
-const handleModelSelect = (option) => {
-  // This can be expanded if additional logic is needed when model is selected
-  console.log('Selected model:', option);
-};
+
 const handleFetchEditingModels = async () => {
   if (!editingModel.value) {
     return;
@@ -858,7 +853,7 @@ const handleFetchEditingModels = async () => {
     if (models.length > 0) {
       modelOptions.value = models;
       toast.success(t('modelManager.fetchModelsSuccess', {count: models.length}));
-      
+
       // 如果当前选择的模型不在列表中，默认选择第一个
       if (!models.some(m => m.value === editingModel.value.defaultModel)) {
         editingModel.value.defaultModel = models[0].value;
@@ -916,7 +911,7 @@ const handleFetchNewModels = async () => {
     if (models.length > 0) {
       modelOptions.value = models;
       toast.success(t('modelManager.fetchModelsSuccess', {count: models.length}));
-      
+
       // 默认选择第一个模型
       newModel.value.defaultModel = models[0].value;
     } else {