diff --git a/docs/BUG_HISTORY.md b/docs/BUG_HISTORY.md
index d4d1bc25..4ee154bb 100644
--- a/docs/BUG_HISTORY.md
+++ b/docs/BUG_HISTORY.md
@@ -2832,3 +2832,19 @@
 - 防复发：引擎适配器必须有真实响应形状的契约测试；新增任何映射层必须对照 `scripts/rectification/contracts.py:SCOREABLE_EVENT_KINDS`；RPC 重放/幂等语义以“先重放后校验、重放校验已落库状态”为唯一实现顺序；迁移修改必须在真实 PostgreSQL 上从空库全量应用并重跑。
 - 相关记录：BUG-163、BUG-112
 - 修复版本：本地 staging 候选（未 push / deploy）
+
+## BUG-165 | 合并咨询 Agentic runtime 后生时校正执行步骤复用共享 activity 字段导致构建失败
+
+- 状态：resolved（local candidate，待 staging gate）
+- 首次发现：2026-08-11
+- 最近更新：2026-08-11
+- 影响面：`RectificationAgenticChat`、共享 `ChatMessageView`、Next.js production type-check
+- 用户现象：生时校正与最新 staging 的咨询 Agentic runtime 单独测试均通过，但合并后 `next build` 在 `rectification-agentic-chat.tsx` 报 `string[]` 不能赋给结构化 `AgentActivityView`。
+- 触发条件：将 V9 生时校正分支合入包含咨询 Agentic runtime 的最新 `origin/staging`，再运行 production build。
+- 根因：并行开发期间，共享 `ChatMessageView.activity` 从通用状态扩展为咨询 runtime 使用的单个 `{ phase, label }`；生时校正把执行回执的多步骤 `string[]` 也命名为 `activity`。聚焦源码/运行测试没有跨两个 runtime 做 TypeScript 组合检查，只有 production build 暴露交叉类型冲突。
+- 修复：生时校正的持久化/流式回执步骤改为独立 `receiptActivity: readonly string[]`，只用于折叠的“本轮做了什么”；共享 `activity` 继续由咨询 runtime 独占并保持 `{ phase, label }` 合同，不改其 UI 与状态映射。
+- 验证：合并最新 staging 后，`rectification-v9-stream`、`rectification-agentic-entry`、`chat-stream-layout` 共 36/36 通过；目标 ESLint 通过；Next.js 16.2.10 production build 完成 type-check、60 个静态页面生成与 route 列表收口；`git diff --check` 通过。
+- 防复发：生时校正执行回执与咨询即时 activity 必须使用不同字段；任何同时修改 `ChatMessageView` 与专用聊天 surface 的分支，合并最新 staging 后必须运行共享 layout 测试和 production build，不能只依赖各自聚焦测试。
+- 相关记录：BUG-162、BUG-163、BUG-164
+- 复发自：无（并行 runtime 合并冲突）
+- 修复版本：本次 staging 候选
diff --git a/frontend/src/components/rectification-agentic-chat.tsx b/frontend/src/components/rectification-agentic-chat.tsx
index 613fdbc2..e0be9cce 100644
--- a/frontend/src/components/rectification-agentic-chat.tsx
+++ b/frontend/src/components/rectification-agentic-chat.tsx
@@ -57,7 +57,8 @@ type RectificationAgenticChatProps = Readonly<{
 
 type RenderMessage = ChatMessageView & {
   renderKey: string;
-  activity?: readonly string[];
+  /** V9 execution-receipt steps; separate from shared consultation activity. */
+  receiptActivity?: readonly string[];
   receiptStatus?: string;
 };
 
@@ -119,7 +120,7 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
           text: turn.text ?? "",
           renderKey: key,
           state: turn.status === "completed" ? "settled" : "thinking",
-          activity: activityFromReceipt(turn.receipt),
+          receiptActivity: activityFromReceipt(turn.receipt),
           receiptStatus: turn.receipt?.status,
         }];
       }
@@ -212,7 +213,7 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
       ...(action === "message"
         ? [{ role: "user", text: trimmed, renderKey: userRenderKey, state: "settled" } satisfies RenderMessage]
         : []),
-      { role: "assistant", text: "", renderKey: assistantRenderKey, state: "thinking", activity: [] },
+      { role: "assistant", text: "", renderKey: assistantRenderKey, state: "thinking", receiptActivity: [] },
     ]);
     setDraft("");
 
@@ -293,7 +294,7 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
               activitySet.add(event.type);
               liveActivity = [...liveActivity, labelForPhase(event.type)];
               setMessages((current) => current.map((message) => message.renderKey === assistantRenderKey
-                ? { ...message, activity: liveActivity }
+                ? { ...message, receiptActivity: liveActivity }
                 : message));
             }
           }
@@ -304,7 +305,7 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
       const succeeded = completed && !streamFailed && Boolean(parsed.text);
       setMessages((current) => succeeded
         ? current.map((message) => message.renderKey === assistantRenderKey
-          ? { ...message, text: parsed.text, suggestions: parsed.suggestions, state: "settled", activity: liveActivity }
+          ? { ...message, text: parsed.text, suggestions: parsed.suggestions, state: "settled", receiptActivity: liveActivity }
           : message)
         : current.filter((message) => message.renderKey !== assistantRenderKey));
       setSuggestions(succeeded ? parsed.suggestions : []);
@@ -386,11 +387,11 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
           {messages.map((message) => (
             <div key={message.renderKey} className="rectification-message-wrap">
               <ChatMessageRow message={message} />
-              {message.activity && message.activity.length > 0 && (
+              {message.receiptActivity && message.receiptActivity.length > 0 && (
                 <details className="rectification-activity">
                   <summary>本轮做了什么</summary>
                   <ol>
-                    {message.activity.map((step) => <li key={step}>{step}</li>)}
+                    {message.receiptActivity.map((step) => <li key={step}>{step}</li>)}
                   </ol>
                 </details>
               )}