diff --git a/src/renderer/components/thread/ChatPane/ChatPane.tsx b/src/renderer/components/thread/ChatPane/ChatPane.tsx
index 73aa0d59..696dd7cb 100644
--- a/src/renderer/components/thread/ChatPane/ChatPane.tsx
+++ b/src/renderer/components/thread/ChatPane/ChatPane.tsx
@@ -1,13 +1,10 @@
 import { useEffect, useMemo, useRef, useState } from "react";
-import { Surface } from "@heroui/react";
-import { Trans, useLingui } from "@lingui/react/macro";
+import { Trans } from "@lingui/react/macro";
 import { useShallow } from "zustand/react/shallow";
 import { isThreadTurnActive, type ProjectLocation, type Thread } from "@/shared/contracts";
 import { resolveGrokSessionDir } from "@/shared/grokSessionMedia";
 import { isHomeProjectId } from "@/shared/homeScope";
-import { chatMessageSurfaceClass } from "./parts/items/chatMessageSurface";
 import { readBridge } from "@/renderer/bridge";
-import { useShimmerRef } from "@/renderer/thinkingAnimator";
 import { useScrollFade } from "@/renderer/hooks/useScrollFade";
 import { useThreadHasBackgroundActivity } from "@/renderer/hooks/uiSelectors";
 import { useAppStore } from "@/renderer/state/appStore";
@@ -24,7 +21,6 @@ import {
 import { useFileEditorStore } from "@/renderer/state/fileEditorStore";
 import { useProjectRootNames } from "@/renderer/state/projectRootNamesStore";
 import { useProjectTreeStore } from "@/renderer/state/projectTreeStore";
-import { formatElapsed } from "@/renderer/utils/formatTime";
 import {
   buildFileEditorContext,
   openFileInEditor,
@@ -34,6 +30,7 @@ import { showSubAgentPanel } from "@/renderer/actions/panelActions";
 import { ChatFindBar, type ScrollToIndex } from "@/renderer/components/find/ChatFindBar";
 import { ChatPaneActionsContext, type ChatPaneActions } from "./chatPaneActionsContext";
 import { ChatScrollControls, type ChatScrollControlsHandle } from "./ChatScrollControls";
+import { ChatTurnElapsedFooter, type TurnTiming } from "./ChatTurnElapsed";
 import { selectVisibleThreadTimelineEntries, type ChatTimelineEntry } from "./chatPaneSelectors";
 import { shouldMarkUserScrollIntentFromPointerTarget } from "./chatScrollGeometry";
 import { normalizeChatProjectPath } from "./chatPathUtils";
@@ -369,7 +366,7 @@ export function ChatPane(props: ChatPaneProps) {
             }
             footer={
               showTailLoader && tailTurn ? (
-                <ChatTailLoader turn={tailTurn} isPaused={isTurnPaused} />
+                <ChatTurnElapsedFooter turn={tailTurn} isPaused={isTurnPaused} />
               ) : null
             }
             onWheelCapture={(event) => {
@@ -457,11 +454,6 @@ export function ChatPane(props: ChatPaneProps) {
   );
 }
 
-interface TurnTiming {
-  startedAt: number;
-  endedAt: number | null;
-}
-
 interface CompletedTurnTiming extends TurnTiming {
   anchorItemId: string | null;
   endedAt: number;
@@ -514,91 +506,6 @@ function selectMostRecentDisplayableCompletedTurn(
   return null;
 }
 
-function ChatTailLoader({ turn, isPaused }: { turn: TurnTiming; isPaused: boolean }) {
-  return (
-    <div className="mx-auto w-full max-w-[920px]">
-      <Surface variant="transparent" className={chatMessageSurfaceClass}>
-        <div className="inline-flex items-center gap-1.5 text-[length:var(--lc-chat-font-size-meta)] text-foreground-muted">
-          <WorkingFor turn={turn} isPaused={isPaused} />
-        </div>
-      </Surface>
-    </div>
-  );
-}
-
-/**
- * Self-ticking elapsed-time label. While `turn.endedAt` is null, ticks every
- * second as "Working for N"; once set, freezes as "Worked for N". When
- * `isPaused` is true (e.g. the runtime is blocked on a user-input prompt) the
- * counter freezes at its current value and the paused interval is excluded
- * from the elapsed total once it resumes. Mutates `textContent` directly via
- * a ref instead of calling `setState` so the per-second tick produces zero
- * React commits — important while the rest of the chat is potentially
- * streaming.
- */
-function WorkingFor({ turn, isPaused }: { turn: TurnTiming; isPaused: boolean }) {
-  const { t } = useLingui();
-  const textRef = useRef<HTMLSpanElement>(null);
-  const pauseStateRef = useRef<{ accumulatedPauseMs: number; pausedSinceMs: number | null }>({
-    accumulatedPauseMs: 0,
-    pausedSinceMs: null,
-  });
-
-  useEffect(() => {
-    pauseStateRef.current = { accumulatedPauseMs: 0, pausedSinceMs: null };
-  }, [turn.startedAt, turn.endedAt]);
-
-  useEffect(() => {
-    const update = () => {
-      const node = textRef.current;
-      if (!node) return;
-      if (turn.endedAt !== null) {
-        const elapsedSeconds = Math.max(0, Math.floor((turn.endedAt - turn.startedAt) / 1000));
-        const elapsed = formatElapsed(elapsedSeconds);
-        const text = elapsedSeconds < 1 ? "" : t`Worked for ${elapsed}`;
-        node.textContent = text;
-        node.dataset.poracodeShimmerText = text;
-        return;
-      }
-      const pauseState = pauseStateRef.current;
-      const now = Date.now();
-      const currentPauseMs =
-        pauseState.pausedSinceMs !== null ? Math.max(0, now - pauseState.pausedSinceMs) : 0;
-      const elapsedMs = now - turn.startedAt - pauseState.accumulatedPauseMs - currentPauseMs;
-      const elapsedSeconds = Math.max(0, Math.floor(elapsedMs / 1000));
-      const elapsed = formatElapsed(elapsedSeconds);
-      const text = elapsedSeconds < 1 ? "" : t`Working for ${elapsed}`;
-      node.textContent = text;
-      node.dataset.poracodeShimmerText = text;
-    };
-
-    if (isPaused) {
-      if (pauseStateRef.current.pausedSinceMs === null) {
-        pauseStateRef.current.pausedSinceMs = Date.now();
-      }
-      update();
-      return;
-    }
-
-    if (pauseStateRef.current.pausedSinceMs !== null) {
-      pauseStateRef.current.accumulatedPauseMs += Math.max(
-        0,
-        Date.now() - pauseStateRef.current.pausedSinceMs,
-      );
-      pauseStateRef.current.pausedSinceMs = null;
-    }
-    update();
-    if (turn.endedAt !== null) return;
-    const id = setInterval(update, 1000);
-    return () => clearInterval(id);
-  }, [turn.startedAt, turn.endedAt, isPaused, t]);
-
-  const isThinking = !isPaused && turn.endedAt === null;
-  useShimmerRef(textRef, isThinking);
-  const className = isThinking ? "poracode-thinking-text" : "text-muted";
-  return <span ref={textRef} className={className} aria-live="polite" />;
-}
-
 function isScrollNavigationKey(key: string): boolean {
   return (
     key === "ArrowUp" ||
diff --git a/src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx b/src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
new file mode 100644
index 00000000..689b3b43
--- /dev/null
+++ b/src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
@@ -0,0 +1,102 @@
+import { useEffect, useRef } from "react";
+import { Surface } from "@heroui/react";
+import { useLingui } from "@lingui/react/macro";
+import { useShimmerRef } from "@/renderer/thinkingAnimator";
+import { formatElapsed } from "@/renderer/utils/formatTime";
+import { chatMessageSurfaceClass } from "./parts/items/chatMessageSurface";
+
+export interface TurnTiming {
+  startedAt: number;
+  endedAt: number | null;
+}
+
+export function ChatTurnElapsedFooter({
+  turn,
+  isPaused = false,
+}: {
+  turn: TurnTiming;
+  isPaused?: boolean;
+}) {
+  return (
+    <div className="mx-auto w-full max-w-[920px]">
+      <Surface variant="transparent" className={chatMessageSurfaceClass}>
+        <div className="inline-flex items-center gap-1.5 text-[length:var(--lc-chat-font-size-meta)] text-foreground-muted">
+          <WorkingFor turn={turn} isPaused={isPaused} />
+        </div>
+      </Surface>
+    </div>
+  );
+}
+
+/**
+ * Self-ticking elapsed-time label. While `turn.endedAt` is null, ticks every
+ * second as "Working for N"; once set, freezes as "Worked for N". When
+ * `isPaused` is true (e.g. the runtime is blocked on a user-input prompt) the
+ * counter freezes at its current value and the paused interval is excluded
+ * from the elapsed total once it resumes. Mutates `textContent` directly via
+ * a ref instead of calling `setState` so the per-second tick produces zero
+ * React commits — important while the rest of the chat is potentially
+ * streaming.
+ */
+function WorkingFor({ turn, isPaused }: { turn: TurnTiming; isPaused: boolean }) {
+  const { t } = useLingui();
+  const textRef = useRef<HTMLSpanElement>(null);
+  const pauseStateRef = useRef<{ accumulatedPauseMs: number; pausedSinceMs: number | null }>({
+    accumulatedPauseMs: 0,
+    pausedSinceMs: null,
+  });
+
+  useEffect(() => {
+    pauseStateRef.current = { accumulatedPauseMs: 0, pausedSinceMs: null };
+  }, [turn.startedAt, turn.endedAt]);
+
+  useEffect(() => {
+    const update = () => {
+      const node = textRef.current;
+      if (!node) return;
+      if (turn.endedAt !== null) {
+        const elapsedSeconds = Math.max(0, Math.floor((turn.endedAt - turn.startedAt) / 1000));
+        const elapsed = formatElapsed(elapsedSeconds);
+        const text = elapsedSeconds < 1 ? "" : t`Worked for ${elapsed}`;
+        node.textContent = text;
+        node.dataset.poracodeShimmerText = text;
+        return;
+      }
+      const pauseState = pauseStateRef.current;
+      const now = Date.now();
+      const currentPauseMs =
+        pauseState.pausedSinceMs !== null ? Math.max(0, now - pauseState.pausedSinceMs) : 0;
+      const elapsedMs = now - turn.startedAt - pauseState.accumulatedPauseMs - currentPauseMs;
+      const elapsedSeconds = Math.max(0, Math.floor(elapsedMs / 1000));
+      const elapsed = formatElapsed(elapsedSeconds);
+      const text = elapsedSeconds < 1 ? "" : t`Working for ${elapsed}`;
+      node.textContent = text;
+      node.dataset.poracodeShimmerText = text;
+    };
+
+    if (isPaused) {
+      if (pauseStateRef.current.pausedSinceMs === null) {
+        pauseStateRef.current.pausedSinceMs = Date.now();
+      }
+      update();
+      return;
+    }
+
+    if (pauseStateRef.current.pausedSinceMs !== null) {
+      pauseStateRef.current.accumulatedPauseMs += Math.max(
+        0,
+        Date.now() - pauseStateRef.current.pausedSinceMs,
+      );
+      pauseStateRef.current.pausedSinceMs = null;
+    }
+    update();
+    if (turn.endedAt !== null) return;
+    const id = setInterval(update, 1000);
+    return () => clearInterval(id);
+  }, [turn.startedAt, turn.endedAt, isPaused, t]);
+
+  const isThinking = !isPaused && turn.endedAt === null;
+  useShimmerRef(textRef, isThinking);
+  const className = isThinking ? "poracode-thinking-text" : "text-muted";
+  return <span ref={textRef} className={className} aria-live="polite" />;
+}
diff --git a/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.test.tsx b/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.test.tsx
index bb09f8df..d3a0334c 100644
--- a/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.test.tsx
+++ b/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.test.tsx
@@ -1,4 +1,4 @@
-import { screen, waitFor, within } from "@testing-library/react";
+import { fireEvent, screen, waitFor, within } from "@testing-library/react";
 import { beforeEach, describe, expect, it, vi } from "vitest";
 import type { ProjectLocation, ToolCallPayload } from "@/shared/contracts";
 import { AppProvider } from "@/renderer/components/ui/provider";
@@ -15,6 +15,7 @@ const mockBridge = {
   subagentUnsubscribe:
     vi.fn<(payload: { threadId: string; parentItemId: string }) => Promise<void>>(),
 };
+const mockScrollToEnd = vi.hoisted(() => vi.fn<() => Promise<void>>());
 
 type MockLegendProps = {
   data: readonly ChatTimelineEntry[];
@@ -26,6 +27,8 @@ type MockLegendProps = {
   className?: string;
   contentContainerClassName?: string;
   contentContainerStyle?: React.CSSProperties;
+  style?: React.CSSProperties;
+  onWheelCapture?: React.WheelEventHandler<HTMLDivElement>;
   onLoad?: () => void;
 };
 
@@ -44,11 +47,17 @@ vi.mock("@legendapp/list/react", async () => {
           sizes: new Map(),
           listen: () => () => undefined,
         }),
-        scrollToEnd: () => Promise.resolve(),
+        scrollToEnd: mockScrollToEnd,
       }));
       React.useLayoutEffect(() => onLoadRef.current?.(), []);
       return (
-        <div ref={scrollRef} className={props.className} data-poracode-chat-scroller="true">
+        <div
+          ref={scrollRef}
+          className={props.className}
+          style={props.style}
+          data-poracode-chat-scroller="true"
+          onWheelCapture={props.onWheelCapture}
+        >
           <div
             className={`legend-list-content-container ${props.contentContainerClassName ?? ""}`}
             style={props.contentContainerStyle}
@@ -77,6 +86,7 @@ describe("SubAgentContent", () => {
   beforeEach(() => {
     mockBridge.subagentSubscribe.mockReset().mockResolvedValue({ history: [] });
     mockBridge.subagentUnsubscribe.mockReset().mockResolvedValue(undefined);
+    mockScrollToEnd.mockReset().mockResolvedValue(undefined);
     useAppStore.setState({
       runtimeItemIdsByThread: {},
       runtimeItemsByIdByThread: {},
@@ -135,6 +145,78 @@ describe("SubAgentContent", () => {
     expect(icons[1]).toHaveClass("size-3.5");
   });
 
+  it("reuses the main chat fade, sticky-bottom controls, and live elapsed footer", async () => {
+    const threadId = "thread-1";
+    const parentItem: RuntimeChatItem = {
+      ...makeSubAgentItem("parent-1"),
+      startedAt: Date.now() - 70_000,
+    };
+
+    useAppStore.setState({
+      runtimeItemIdsByThread: { [threadId]: [parentItem.id] },
+      runtimeItemsByIdByThread: {
+        [threadId]: {
+          [parentItem.id]: parentItem,
+        },
+      },
+      runtimeStructuralVersionByThread: { [threadId]: 1 },
+    });
+
+    const view = render(
+      <SubAgentContent threadId={threadId} parentItemId={parentItem.id} hideHeader />,
+    );
+
+    expect(await screen.findByText("Working for 1m 10s")).toBeInTheDocument();
+    await waitFor(() => expect(mockScrollToEnd).toHaveBeenCalled());
+    const scroller = view.container.querySelector<HTMLElement>(
+      '[data-poracode-chat-scroller="true"]',
+    );
+    expect(scroller).not.toBeNull();
+    expect(scroller?.style.maskImage).toContain("var(--top-fade-size");
+    const scrollButton = screen.getByRole("button", { name: "Scroll to bottom" });
+    expect(scrollButton).toHaveClass("opacity-0");
+
+    Object.defineProperties(scroller!, {
+      clientHeight: { configurable: true, value: 200 },
+      scrollHeight: { configurable: true, value: 1_000 },
+    });
+    fireEvent.wheel(scroller!, { deltaY: -10 });
+    scroller!.scrollTop = 100;
+    fireEvent.scroll(scroller!);
+
+    await waitFor(() => expect(scrollButton).toHaveClass("opacity-80"));
+    mockScrollToEnd.mockClear();
+    fireEvent.click(scrollButton);
+    await waitFor(() => expect(mockScrollToEnd).toHaveBeenCalled());
+  });
+
+  it("shows the frozen subagent duration after completion", async () => {
+    const threadId = "thread-1";
+    const startedAt = Date.now() - 75_000;
+    const runningParent = makeSubAgentItem("parent-1");
+    const parentItem: RuntimeChatItem = {
+      ...runningParent,
+      state: "completed",
+      startedAt,
+      completedAt: startedAt + 75_000,
+      payload: { ...(runningParent.payload as ToolCallPayload), status: "success" },
+    };
+
+    useAppStore.setState({
+      runtimeItemIdsByThread: { [threadId]: [parentItem.id] },
+      runtimeItemsByIdByThread: {
+        [threadId]: {
+          [parentItem.id]: parentItem,
+        },
+      },
+      runtimeStructuralVersionByThread: { [threadId]: 1 },
+    });
+
+    render(<SubAgentContent threadId={threadId} parentItemId={parentItem.id} hideHeader />);
+
+    expect(await screen.findByText("Worked for 1m 15s")).toBeInTheDocument();
+  });
+
   it("splits a Crossagent name and model selection into a two-line route header", () => {
     const threadId = "thread-1";
     const parentItem: RuntimeChatItem = {
diff --git a/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.tsx b/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.tsx
index 886d3b08..867a7215 100644
--- a/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.tsx
+++ b/src/renderer/components/thread/ChatPane/parts/items/SubAgentOverlay.tsx
@@ -4,15 +4,21 @@ import { Bot, X } from "lucide-react";
 import type { ProjectLocation, ToolCallPayload } from "@/shared/contracts";
 import { PixelLoader } from "@/renderer/components/common/PixelLoader";
 import { readBridge } from "@/renderer/bridge";
+import { useScrollFade } from "@/renderer/hooks/useScrollFade";
 import { useAppStore } from "@/renderer/state/appStore";
 import { useSharedSettings } from "@/renderer/state/sharedSettingsStore";
-import { getRuntimeItemPayload } from "@/renderer/state/slices/runtimeEventSlice";
+import {
+  getRuntimeItemPayload,
+  type RuntimeChatItem,
+} from "@/renderer/state/slices/runtimeEventSlice";
 import { guiChatFontCssVars } from "../../chatFontVars";
 import {
   getChildTimelineEntriesStoreSelector,
   getRuntimeItemStoreSelector,
   type ChatTimelineEntry,
 } from "../../chatPaneSelectors";
+import { ChatScrollControls, type ChatScrollControlsHandle } from "../../ChatScrollControls";
+import { ChatTurnElapsedFooter, type TurnTiming } from "../../ChatTurnElapsed";
 import { MessageList } from "../MessageList";
 import { buildSubAgentProgressParts } from "./subAgentProgressMeta";
 import { deriveToolDisplay, isCrossagentTool, isWorkflowTool } from "./toolDisplay";
@@ -133,6 +139,7 @@ export function SubAgentContent({
         isRunning,
       }
     : null;
+  const turn = resolveSubAgentTurnTiming(item, payload, isRunning);
 
   const renderWorkflow = !!(workflow && workflow.manifestPath);
   return (
@@ -155,8 +162,10 @@ export function SubAgentContent({
       ) : (
         <ChildList
           threadId={threadId}
+          parentItemId={parentItemId}
           entries={childEntries}
           stickToBottom={isRunning}
+          turn={turn}
           workflow={workflow}
           workflowProgress={workflowProgress}
         />
@@ -319,42 +328,102 @@ function Shell({
 
 function ChildList({
   threadId,
+  parentItemId,
   entries,
   stickToBottom,
+  turn,
   workflow,
   workflowProgress,
 }: {
   threadId: string;
+  parentItemId: string;
   entries: readonly ChatTimelineEntry[];
   stickToBottom: boolean;
+  turn: TurnTiming | null;
   workflow: WorkflowInfo | null;
   workflowProgress: WorkflowOverlayProgress | null;
 }) {
+  const contentRef = useRef<HTMLDivElement>(null);
+  const scrollControlsRef = useRef<ChatScrollControlsHandle>(null);
+  const virtualScrollToBottomRef = useRef<(() => void) | null>(null);
+  const { setScrollContainer, scrollRef, scrollFadeStyle } = useScrollFade<HTMLDivElement>({
+    contentRef,
+  });
+
   return (
-    <MessageList
-      threadId={threadId}
-      entries={entries}
-      isTurnActive={stickToBottom}
-      markTailAsLive={stickToBottom}
-      canRevertCheckpoints={false}
-      scrollClassName="min-h-0 flex-1 overflow-y-auto [scrollbar-gutter:stable]"
-      contentClassName="poracode-subagent-list-content min-h-full px-3 pt-3"
-      header={
-        workflow ? <WorkflowOverlayHeader workflow={workflow} progress={workflowProgress} /> : null
-      }
-      emptyContent={
-        workflow ? (
-          <WorkflowEmptyState progress={workflowProgress} />
-        ) : (
-          <p className="text-sm text-foreground-muted">
-            <Trans>Working…</Trans>
-          </p>
-        )
-      }
-    />
+    <div className="relative min-h-0 flex-1">
+      <MessageList
+        threadId={threadId}
+        entries={entries}
+        isTurnActive={stickToBottom}
+        markTailAsLive={stickToBottom}
+        canRevertCheckpoints={false}
+        setScrollContainer={setScrollContainer}
+        scrollContentRef={contentRef}
+        onContentHeightChange={() => scrollControlsRef.current?.onContentHeightChange()}
+        onVirtualizerLayoutChange={() => scrollControlsRef.current?.beginVirtualizerLayoutChange()}
+        onLiveVirtualizerLayoutChange={() =>
+          scrollControlsRef.current?.beginLiveVirtualizerLayoutChange()
+        }
+        registerVirtualScrollToBottom={(handler) => {
+          virtualScrollToBottomRef.current = handler;
+        }}
+        scrollClassName="h-full min-h-0 overflow-y-auto [overflow-anchor:none] [scrollbar-gutter:stable]"
+        scrollStyle={scrollFadeStyle}
+        contentClassName="poracode-subagent-list-content min-h-full px-3 pt-3"
+        header={
+          workflow ? (
+            <WorkflowOverlayHeader workflow={workflow} progress={workflowProgress} />
+          ) : null
+        }
+        footer={turn ? <ChatTurnElapsedFooter turn={turn} /> : null}
+        emptyContent={
+          workflow ? (
+            <WorkflowEmptyState progress={workflowProgress} />
+          ) : (
+            <p className="text-sm text-foreground-muted">
+              <Trans>Working…</Trans>
+            </p>
+          )
+        }
+        onWheelCapture={(event) => {
+          if (event.deltaY >= 0) return;
+          scrollControlsRef.current?.markUserScrollIntent();
+          scrollControlsRef.current?.disableStickToBottom();
+        }}
+      />
+      <ChatScrollControls
+        ref={scrollControlsRef}
+        scrollRef={scrollRef}
+        contentRef={contentRef}
+        layoutChangeToken={null}
+        tailEntryId={entries.at(-1)?.id ?? null}
+        threadId={`${threadId}:subagent:${parentItemId}`}
+        tailLoaderVisible={turn !== null}
+        initialScrollSettled
+        initialScrollRevealDelayMs={0}
+        virtualScrollToBottomRef={virtualScrollToBottomRef}
+        onInitialScrollSettled={() => undefined}
+      />
+    </div>
   );
 }
 
+function resolveSubAgentTurnTiming(
+  item: RuntimeChatItem,
+  payload: ToolCallPayload | undefined,
+  isRunning: boolean,
+): TurnTiming | null {
+  if (isRunning) {
+    return item.startedAt === undefined ? null : { startedAt: item.startedAt, endedAt: null };
+  }
+  const durationMs =
+    item.startedAt !== undefined && item.completedAt !== undefined
+      ? item.completedAt - item.startedAt
+      : payload?.progress?.durationMs;
+  return durationMs === undefined ? null : { startedAt: 0, endedAt: Math.max(0, durationMs) };
+}
+
 function WorkflowOverlayHeader({
   workflow,
   progress,
diff --git a/src/renderer/locales/de/messages.po b/src/renderer/locales/de/messages.po
index 8277eca4..b4990ca8 100644
--- a/src/renderer/locales/de/messages.po
+++ b/src/renderer/locales/de/messages.po
@@ -11793,7 +11793,7 @@ msgstr "Arbeit"
 msgid "Work in the current checkout"
 msgstr "Im aktuellen Checkout arbeiten"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Gearbeitet für {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Workflows"
 msgid "Working"
 msgstr "Arbeiten"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Arbeitet seit {elapsed}"
 
diff --git a/src/renderer/locales/en/messages.po b/src/renderer/locales/en/messages.po
index 9208ad7d..6cd8edc9 100644
--- a/src/renderer/locales/en/messages.po
+++ b/src/renderer/locales/en/messages.po
@@ -11793,7 +11793,7 @@ msgstr "Work"
 msgid "Work in the current checkout"
 msgstr "Work in the current checkout"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Worked for {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Workflows"
 msgid "Working"
 msgstr "Working"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Working for {elapsed}"
 
diff --git a/src/renderer/locales/es/messages.po b/src/renderer/locales/es/messages.po
index 569e0ab5..a4d45f56 100644
--- a/src/renderer/locales/es/messages.po
+++ b/src/renderer/locales/es/messages.po
@@ -11793,7 +11793,7 @@ msgstr "Trabajo"
 msgid "Work in the current checkout"
 msgstr "Trabajar en el checkout actual"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Trabajó durante {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Flujos de trabajo"
 msgid "Working"
 msgstr "Trabajando"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Trabajando durante {elapsed}"
 
diff --git a/src/renderer/locales/fr/messages.po b/src/renderer/locales/fr/messages.po
index 55aa3b66..25835df1 100644
--- a/src/renderer/locales/fr/messages.po
+++ b/src/renderer/locales/fr/messages.po
@@ -11792,7 +11792,7 @@ msgstr "Travail"
 msgid "Work in the current checkout"
 msgstr "Travailler dans la copie de travail actuelle"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "A travaillé pendant {elapsed}"
@@ -11835,7 +11835,7 @@ msgstr "Flux de travail"
 msgid "Working"
 msgstr "En cours"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "En cours depuis {elapsed}"
 
diff --git a/src/renderer/locales/ja/messages.po b/src/renderer/locales/ja/messages.po
index c62caf95..1a98479c 100644
--- a/src/renderer/locales/ja/messages.po
+++ b/src/renderer/locales/ja/messages.po
@@ -11791,7 +11791,7 @@ msgstr "作業"
 msgid "Work in the current checkout"
 msgstr "現在のチェックアウトでの作業"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "{elapsed}稼働しました"
@@ -11834,7 +11834,7 @@ msgstr "ワークフロー"
 msgid "Working"
 msgstr "実行中"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "{elapsed}稼働中"
 
diff --git a/src/renderer/locales/ko/messages.po b/src/renderer/locales/ko/messages.po
index e8615d3f..be12ebaf 100644
--- a/src/renderer/locales/ko/messages.po
+++ b/src/renderer/locales/ko/messages.po
@@ -11793,7 +11793,7 @@ msgstr "작업"
 msgid "Work in the current checkout"
 msgstr "현재 체크아웃에서 작업"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "{elapsed} 동안 작업함"
@@ -11836,7 +11836,7 @@ msgstr "워크플로"
 msgid "Working"
 msgstr "작업 중"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "{elapsed} 동안 작업 중"
 
diff --git a/src/renderer/locales/pl/messages.po b/src/renderer/locales/pl/messages.po
index 769aa1fa..6129879c 100644
--- a/src/renderer/locales/pl/messages.po
+++ b/src/renderer/locales/pl/messages.po
@@ -11793,7 +11793,7 @@ msgstr "Praca"
 msgid "Work in the current checkout"
 msgstr "Pracuj w bieżącym checkoucie"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Pracował przez {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Przepływy pracy"
 msgid "Working"
 msgstr "Pracuje"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Praca przez {elapsed}"
 
diff --git a/src/renderer/locales/pt-BR/messages.po b/src/renderer/locales/pt-BR/messages.po
index d37dcaa9..788d2d52 100644
--- a/src/renderer/locales/pt-BR/messages.po
+++ b/src/renderer/locales/pt-BR/messages.po
@@ -11793,7 +11793,7 @@ msgstr "Trabalho"
 msgid "Work in the current checkout"
 msgstr "Trabalhar no checkout atual"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Trabalhou por {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Fluxos de trabalho"
 msgid "Working"
 msgstr "Trabalhando"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Trabalhando por {elapsed}"
 
diff --git a/src/renderer/locales/ru/messages.po b/src/renderer/locales/ru/messages.po
index c413c776..3973c8ae 100644
--- a/src/renderer/locales/ru/messages.po
+++ b/src/renderer/locales/ru/messages.po
@@ -11793,7 +11793,7 @@ msgstr "Работа"
 msgid "Work in the current checkout"
 msgstr "Работать в текущем checkout"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Работал {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Рабочие процессы"
 msgid "Working"
 msgstr "Работает"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Работает {elapsed}"
 
diff --git a/src/renderer/locales/tr/messages.po b/src/renderer/locales/tr/messages.po
index 55f69124..bb8d098d 100644
--- a/src/renderer/locales/tr/messages.po
+++ b/src/renderer/locales/tr/messages.po
@@ -11793,7 +11793,7 @@ msgstr "İş"
 msgid "Work in the current checkout"
 msgstr "Mevcut çalışma kopyasında çalışın"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "{elapsed} boyunca çalıştı"
@@ -11836,7 +11836,7 @@ msgstr "İş akışları"
 msgid "Working"
 msgstr "Çalışıyor"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "{elapsed} boyunca çalışıyor"
 
diff --git a/src/renderer/locales/uk/messages.po b/src/renderer/locales/uk/messages.po
index ce654ec0..99b9b0a2 100644
--- a/src/renderer/locales/uk/messages.po
+++ b/src/renderer/locales/uk/messages.po
@@ -11793,7 +11793,7 @@ msgstr "Робота"
 msgid "Work in the current checkout"
 msgstr "Працювати в поточному checkout"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Працював {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Робочі процеси"
 msgid "Working"
 msgstr "Працює"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Працює {elapsed}"
 
diff --git a/src/renderer/locales/vi/messages.po b/src/renderer/locales/vi/messages.po
index 568b0e95..77708486 100644
--- a/src/renderer/locales/vi/messages.po
+++ b/src/renderer/locales/vi/messages.po
@@ -11793,7 +11793,7 @@ msgstr "công việc"
 msgid "Work in the current checkout"
 msgstr "Làm việc trong checkout hiện tại"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "Đã làm việc trong {elapsed}"
@@ -11836,7 +11836,7 @@ msgstr "Quy trình làm việc"
 msgid "Working"
 msgstr "Đang làm việc"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "Đang làm việc trong {elapsed}"
 
diff --git a/src/renderer/locales/zh-CN/messages.po b/src/renderer/locales/zh-CN/messages.po
index 8362ac85..a8bb4a79 100644
--- a/src/renderer/locales/zh-CN/messages.po
+++ b/src/renderer/locales/zh-CN/messages.po
@@ -11792,7 +11792,7 @@ msgstr "工作"
 msgid "Work in the current checkout"
 msgstr "在当前检出中工作"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 #: src/renderer/components/thread/ChatPane/parts/MessageList.tsx
 msgid "Worked for {elapsed}"
 msgstr "已工作 {elapsed}"
@@ -11835,7 +11835,7 @@ msgstr "工作流程"
 msgid "Working"
 msgstr "工作中"
 
-#: src/renderer/components/thread/ChatPane/ChatPane.tsx
+#: src/renderer/components/thread/ChatPane/ChatTurnElapsed.tsx
 msgid "Working for {elapsed}"
 msgstr "已工作 {elapsed}"
 
diff --git a/src/renderer/state/slices/runtimeEventReducer.ts b/src/renderer/state/slices/runtimeEventReducer.ts
index 142cdef4..8633ac43 100644
--- a/src/renderer/state/slices/runtimeEventReducer.ts
+++ b/src/renderer/state/slices/runtimeEventReducer.ts
@@ -1,4 +1,5 @@
-import type { RuntimeEvent, ThreadContextUsage } from "@/shared/contracts";
+import type { RuntimeEvent, ThreadContextUsage, ToolCallPayload } from "@/shared/contracts";
+import { isDelegatedAgentTool } from "@/shared/toolCallClassification";
 import type { AppStoreState } from "./shared";
 import {
   type CompletedTurnRecord,
@@ -243,6 +244,9 @@ function applyRuntimeEventToRuntimeState(
         id: event.itemId,
         type: event.itemType,
         state: "started",
+        ...(isDelegatedAgentTool(event.payload as ToolCallPayload | undefined)
+          ? { startedAt: Date.now() }
+          : {}),
         payload: event.payload,
         streams: {},
         observedLive: true,
@@ -264,10 +268,15 @@ function applyRuntimeEventToRuntimeState(
       const items = state.runtimeItemsByIdByThread[threadId];
       const prev = items?.[event.itemId];
       if (!prev || !items) return {};
+      const payload = mergePayload(prev.payload, event.payload);
       const next: RuntimeChatItem = {
         ...prev,
         state: prev.state === "completed" ? "completed" : "updated",
-        payload: mergePayload(prev.payload, event.payload),
+        ...(prev.startedAt === undefined &&
+        isDelegatedAgentTool(payload as ToolCallPayload | undefined)
+          ? { startedAt: Date.now() }
+          : {}),
+        payload,
       };
       return {
         runtimeItemsByIdByThread: {
@@ -284,6 +293,7 @@ function applyRuntimeEventToRuntimeState(
       const next: RuntimeChatItem = {
         ...prev,
         state: "completed",
+        ...(prev.startedAt !== undefined ? { completedAt: Date.now() } : {}),
         payload:
           event.payload !== undefined ? mergePayload(prev.payload, event.payload) : prev.payload,
       };
diff --git a/src/renderer/state/slices/runtimeEventSlice.test.ts b/src/renderer/state/slices/runtimeEventSlice.test.ts
index d0b3846d..6eb674e9 100644
--- a/src/renderer/state/slices/runtimeEventSlice.test.ts
+++ b/src/renderer/state/slices/runtimeEventSlice.test.ts
@@ -50,6 +50,30 @@ describe("runtimeEventSlice.applyRuntimeEvent", () => {
     });
   });
 
+  it("records a local completion timestamp without replacing the start timestamp", () => {
+    const startedBefore = Date.now();
+    apply("t1", {
+      type: "item.started",
+      threadId: "t1",
+      itemId: "i1",
+      itemType: "tool_call",
+      payload: { name: "spawnAgent", status: "running", isSubAgent: true },
+    });
+    const startedAt = store.getState().runtimeItemsByIdByThread["t1"]?.["i1"]?.startedAt;
+    expect(startedAt).toBeGreaterThanOrEqual(startedBefore);
+
+    apply("t1", {
+      type: "item.completed",
+      threadId: "t1",
+      itemId: "i1",
+      payload: { status: "success" },
+    });
+
+    const item = store.getState().runtimeItemsByIdByThread["t1"]?.["i1"];
+    expect(item?.startedAt).toBe(startedAt);
+    expect(item?.completedAt).toBeGreaterThanOrEqual(startedAt ?? 0);
+  });
+
   it("is idempotent for repeated item.started with the same id", () => {
     apply("t1", {
       type: "item.started",
diff --git a/src/renderer/state/slices/runtimeEventSlice.ts b/src/renderer/state/slices/runtimeEventSlice.ts
index 472331c2..cfe59aa9 100644
--- a/src/renderer/state/slices/runtimeEventSlice.ts
+++ b/src/renderer/state/slices/runtimeEventSlice.ts
@@ -44,6 +44,9 @@ export interface RuntimeChatItem {
   type: CanonicalItemType;
   /** "started" / "updated" land on items that haven't ended yet; "completed" → final. */
   state: "started" | "updated" | "completed";
+  /** Local wall-clock timing for delegated-agent parents. Not persisted; provider duration is the reload fallback. */
+  startedAt?: number;
+  completedAt?: number;
   /** Last payload object reported via `item.started` or `item.updated`. */
   payload?: unknown;
   /** Streamed content buckets (markdown text, command output, etc.). */