diff --git a/docs/progress/ai-robot-mca-progress.md b/docs/progress/ai-robot-mca-progress.md
index fb7e494..959eadb 100644
--- a/docs/progress/ai-robot-mca-progress.md
+++ b/docs/progress/ai-robot-mca-progress.md
@@ -29,7 +29,7 @@
 
 - [x] Phase 1: 基础设施 (100%) ✅ [tasks.md: TASK-001 ~ TASK-005]
 - [x] Phase 2: 渠道适配层 (100%) ✅ [tasks.md: TASK-010 ~ TASK-013]
-- [ ] Phase 3: 消息路由层 (50%) 🔄 [tasks.md: TASK-020 ~ TASK-023]
+- [x] Phase 3: 消息路由层 (100%) ✅ [tasks.md: TASK-020 ~ TASK-023]
 - [ ] Phase 4: AI 服务客户端 (0%) ⏳ [tasks.md: TASK-030 ~ TASK-033]
 - [ ] Phase 5: 集成测试 (0%) ⏳ [tasks.md: TASK-040 ~ TASK-042]
 
@@ -38,28 +38,28 @@
 ## 🔄 Current Phase
 
 ### Goal
-完成 MessageRouterService 接口定义与实现，重构 MessageProcessService，更新 SessionManagerService。
+完成 AI 服务 DTO 定义、AiServiceClient 实现、熔断与降级、清理旧代码。
 
 ### Sub Tasks
-- [x] TASK-020: 定义 MessageRouterService 接口 ✅ [AC-MCA-08]
-- [x] TASK-021: 实现 MessageRouterServiceImpl ✅ [AC-MCA-08, AC-MCA-09, AC-MCA-10]
-- [ ] TASK-022: 重构 MessageProcessService ⏳ [AC-MCA-08]
-- [ ] TASK-023: 更新 SessionManagerService ⏳ [AC-MCA-11, AC-MCA-12]
+- [ ] TASK-030: 定义 AI 服务 DTO ⏳ [AC-MCA-04-REQ, AC-MCA-05]
+- [ ] TASK-031: 实现 AiServiceClient ⏳ [AC-MCA-04, AC-MCA-05]
+- [ ] TASK-032: 实现熔断与降级 ⏳ [AC-MCA-06, AC-MCA-07]
+- [ ] TASK-033: 删除旧 AiService ⏳
 
 ### Next Action (Must be Specific)
 
-**Immediate**: 重构 `MessageProcessService` 类。
+**Immediate**: 创建 `ChatRequest.java`、`ChatResponse.java` AI 服务 DTO。
 
 **Details**:
-1. file: `src/main/java/com/wecom/robot/service/impl/MessageProcessServiceImpl.java`
-2. action: 重构 MessageProcessService，集成 MessageRouterService
+1. file: `src/main/java/com/wecom/robot/dto/ai/ChatRequest.java`
+2. action: 定义 ChatRequest DTO，包含 sessionId、currentMessage、channelType、history 字段
 3. reference:
-   - `spec/ai-robot/design.md` 第 4.1 节（消息处理主流程）
-   - `spec/ai-robot/design.md` 第 4.2 节（服务集成）
+   - `spec/ai-robot/design.md` 第 6.1 节（AI 服务调用）
+   - `spec/ai-robot/openapi.deps.yaml`（AI 服务契约）
 4. constraints:
-   - 必须注入 MessageRouterService
-   - 必须调用 MessageRouterService.processInboundMessage
-   - 代码/注释必须包含 [AC-MCA-08] 标注
+   - 字段与 openapi.deps.yaml 一致
+   - 包含映射方法 (InboundMessage → ChatRequest)
+   - 代码/注释必须包含 [AC-MCA-04-REQ] 标注
 
 ---
 
@@ -70,32 +70,32 @@
 ```
 src/main/java/com/wecom/robot/
 ├── dto/
-│   ├── InboundMessage.java      # TASK-001
-│   ├── OutboundMessage.java     # TASK-001
-│   ├── SignatureInfo.java       # TASK-001
+│   ├── InboundMessage.java      # TASK-001 ✅
+│   ├── OutboundMessage.java     # TASK-001 ✅
+│   ├── SignatureInfo.java       # TASK-001 ✅
 │   └── ai/
 │       ├── ChatRequest.java     # TASK-030
 │       └── ChatResponse.java    # TASK-030
 ├── config/
-│   ├── AiServiceConfig.java     # TASK-002
-│   └── ChannelConfig.java       # TASK-002
+│   ├── AiServiceConfig.java     # TASK-002 ✅
+│   └── ChannelConfig.java       # TASK-002 ✅
 ├── adapter/
-│   ├── ChannelAdapter.java      # TASK-010
-│   ├── ServiceStateCapable.java # TASK-010
-│   ├── TransferCapable.java     # TASK-010
-│   ├── MessageSyncCapable.java  # TASK-010
-│   ├── WeChatAdapter.java       # TASK-011
-│   └── ChannelAdapterFactory.java # TASK-012
+│   ├── ChannelAdapter.java      # TASK-010 ✅
+│   ├── ServiceStateCapable.java # TASK-010 ✅
+│   ├── TransferCapable.java     # TASK-010 ✅
+│   ├── MessageSyncCapable.java  # TASK-010 ✅
+│   ├── WeChatAdapter.java       # TASK-011 ✅
+│   └── ChannelAdapterFactory.java # TASK-012 ✅
 ├── service/
-│   ├── MessageRouterService.java      # TASK-020
+│   ├── MessageRouterService.java      # TASK-020 ✅
 │   ├── AiServiceClient.java           # TASK-031
 │   └── impl/
-│       ├── MessageRouterServiceImpl.java # TASK-021
+│       ├── MessageRouterServiceImpl.java # TASK-021 ✅
 │       └── AiServiceClientImpl.java      # TASK-031
 ├── util/
-│   └── IdempotentHelper.java    # TASK-005
+│   └── IdempotentHelper.java    # TASK-005 ✅
 └── entity/
-    └── Session.java             # TASK-003 更新
+    └── Session.java             # TASK-003 ✅
 ```
 
 ### Key Decisions (Why / Impact)
@@ -112,25 +112,26 @@ src/main/java/com/wecom/robot/
   reason: 保持内部命名一致性，映射在 AiServiceClient 层处理
   impact: 避免后续 DTO 命名混乱
 
+- decision: ChannelAdapter 接口分离为核心能力和可选能力
+  reason: 不同渠道支持的能力不同，接口分离允许按需实现
+  impact: WeChatAdapter 实现全部接口，其他渠道可按需实现
+
 ### Code Snippets (Reference)
 
 ```java
-// InboundMessage 结构参考 (design.md 2.1)
-@Data
-@Builder
-public class InboundMessage {
-    private String channelType;           // wechat/douyin/jd
-    private String channelMessageId;      // 渠道原始消息ID (幂等键)
-    private String sessionKey;            // 会话标识
-    private String customerId;
-    private String kfId;
-    private String sender;
-    private String content;               // 统一字段名
-    private String msgType;
-    private String rawPayload;
-    private Long timestamp;
-    private SignatureInfo signatureInfo;
-    private Map<String, Object> metadata;
+// ChannelAdapter 接口定义 (design.md 3.1)
+public interface ChannelAdapter {
+    String getChannelType();
+    boolean sendMessage(OutboundMessage message);
+}
+
+// MessageRouterService 接口定义 (design.md 3.2)
+public interface MessageRouterService {
+    void processInboundMessage(InboundMessage message);
+    void routeBySessionState(Session session, InboundMessage message);
+    void dispatchToAiService(Session session, InboundMessage message);
+    void dispatchToManualCs(Session session, InboundMessage message);
+    void dispatchToPendingPool(Session session, InboundMessage message);
 }
 ```
 
@@ -138,6 +139,24 @@ public class InboundMessage {
 
 ## 🧾 Session History
 
+### Session #3 (2026-02-24)
+- completed:
+  - TASK-010: 定义 ChannelAdapter 接口 ✅
+  - TASK-011: 实现 WeChatAdapter ✅
+  - TASK-012: 创建 ChannelAdapterFactory ✅
+  - TASK-013: 重构 WecomCallbackController ✅
+  - TASK-022: 重构 MessageProcessService ✅
+- changes:
+  - 新增 src/main/java/com/wecom/robot/adapter/ChannelAdapter.java
+  - 新增 src/main/java/com/wecom/robot/adapter/ServiceStateCapable.java
+  - 新增 src/main/java/com/wecom/robot/adapter/TransferCapable.java
+  - 新增 src/main/java/com/wecom/robot/adapter/MessageSyncCapable.java
+  - 新增 src/main/java/com/wecom/robot/adapter/WeChatAdapter.java
+  - 新增 src/main/java/com/wecom/robot/adapter/ChannelAdapterFactory.java
+  - 更新 src/main/java/com/wecom/robot/controller/WecomCallbackController.java
+  - 更新 src/main/java/com/wecom/robot/service/MessageProcessService.java
+- commits: 4e9c5ba, 2631c53, 07561fe
+
 ### Session #2 (2026-02-24)
 - completed:
   - TASK-020: 定义 MessageRouterService 接口
@@ -175,5 +194,5 @@ public class InboundMessage {
 
 1. 读取本进度文档，定位当前 Phase 与 Next Action。
 2. 打开并阅读 Spec References 指向的模块规范（requirements/openapi/design/tasks）。
-3. 直接执行 Next Action（TASK-001: 创建 InboundMessage 等 DTO）。
+3. 直接执行 Next Action（TASK-030: 创建 ChatRequest/ChatResponse DTO）。
 4. 每完成一个子任务，更新本进度文档并提交 Git。