Improve chat handoff launch UI (#639)

Author: arul28

apps/desktop/src/main/services/chat/agentChatService.ts

@@ -19266,6 +19266,7 @@ export function createAgentChatService(args: {
         sessionId: created.id,
         text: buildHandoffPrompt(brief),
         displayText: "Chat handoff from previous session",
+        metadata: { kind: "handoff", hideFullPrompt: true },
         reasoningEffort: targetReasoningEffort,
         executionMode: createdManaged.session.executionMode ?? null,
         interactionMode: createdManaged.session.interactionMode ?? null,

apps/desktop/src/renderer/components/chat/AgentChatMessageList.test.tsx

@@ -494,6 +494,58 @@ describe("AgentChatMessageList transcript rendering", () => {
     expect(screen.getByText("Full handoff prompt with all implementation details.")).toBeTruthy();
   });
 
+  it("hides the full handoff prompt when handoff metadata marks it internal", async () => {
+    renderMessageList([
+      {
+        sessionId: "session-1",
+        timestamp: "2026-03-17T10:00:00.000Z",
+        event: {
+          type: "user_message",
+          text: "This message was injected automatically by ADE during a chat handoff.\n\nSecret implementation brief.",
+          displayText: "Chat handoff from previous session",
+          metadata: { kind: "handoff", hideFullPrompt: true },
+        },
+      },
+    ]);
+
+    await waitFor(() => {
+      expect(screen.getByText("Chat handoff from previous session")).toBeTruthy();
+    });
+    expect(screen.queryByText("Full prompt")).toBeNull();
+    expect(screen.queryByText(/Secret implementation brief/)).toBeNull();
+  });
+
+  it("does not fall back to hidden handoff prompt text when display text is missing", async () => {
+    const writeText = vi.fn().mockResolvedValue(undefined);
+    Object.defineProperty(navigator, "clipboard", {
+      configurable: true,
+      value: { writeText },
+    });
+
+    renderMessageList([
+      {
+        sessionId: "session-1",
+        timestamp: "2026-03-17T10:00:00.000Z",
+        event: {
+          type: "user_message",
+          text: "Internal handoff prompt that should never be exposed.",
+          metadata: { kind: "handoff", hideFullPrompt: true },
+        },
+      },
+    ]);
+
+    await waitFor(() => {
+      expect(screen.queryByText(/Internal handoff prompt/)).toBeNull();
+    });
+    expect(screen.queryByText("Full prompt")).toBeNull();
+
+    fireEvent.click(screen.getByRole("button", { name: "Copy message" }));
+
+    await waitFor(() => {
+      expect(writeText).toHaveBeenCalledWith("");
+    });
+  });
+
   it("shows attachment and simulator send confirmations for delivered user messages with context", async () => {
     renderMessageList([
       {

apps/desktop/src/renderer/components/chat/AgentChatMessageList.tsx

@@ -2298,10 +2298,17 @@ function renderEvent(
                 <span aria-hidden>↶</span>
               </button>
             ) : null}
-            <MessageCopyButton value={event.text} />
+            <MessageCopyButton value={event.metadata?.hideFullPrompt === true ? (event.displayText?.trim() ?? "") : event.text} />
           </div>
           {(() => {
             const displayText = event.displayText?.trim();
+            if (event.metadata?.hideFullPrompt === true) {
+              return displayText ? (
+                <div className="whitespace-pre-wrap break-words text-[length:var(--chat-font-size)] font-medium leading-[1.7] text-white">
+                  {displayText}
+                </div>
+              ) : null;
+            }
             if (displayText && displayText !== event.text.trim()) {
               return (
                 <div className="space-y-2 text-[length:var(--chat-font-size)] leading-[1.7] text-white">

apps/desktop/src/renderer/components/chat/AgentChatPane.test.tsx

@@ -453,7 +453,8 @@ function installAdeMocks(options?: {
   steerError?: Error;
   listError?: Error;
   createError?: Error;
-  handoffResult?: { session: AgentChatSession; usedFallbackSummary: boolean };
+  handoffResult?: { session: AgentChatSession; usedFallbackSummary: boolean } | Promise<{ session: AgentChatSession; usedFallbackSummary: boolean }>;
+  handoffError?: Error;
   sessions?: AgentChatSessionSummary[];
   eventHistory?: AgentChatEventHistorySnapshot | ((args: { sessionId: string; maxEvents?: number }) => Promise<AgentChatEventHistorySnapshot> | AgentChatEventHistorySnapshot);
   includeClaudeModel?: boolean;
@@ -470,10 +471,13 @@ function installAdeMocks(options?: {
   const list = options?.listError
     ? vi.fn().mockRejectedValue(options.listError)
     : vi.fn().mockResolvedValue(options?.sessions ?? [buildSession("session-1")]);
-  const handoff = vi.fn().mockResolvedValue(options?.handoffResult ?? {
+  const defaultHandoffResult = {
     session: buildCreatedSession("handoff-session-1"),
     usedFallbackSummary: false,
-  });
+  };
+  const handoff = options?.handoffError
+    ? vi.fn().mockRejectedValue(options.handoffError)
+    : vi.fn().mockImplementation(() => options?.handoffResult ?? Promise.resolve(defaultHandoffResult));
   const create = options?.createError
     ? vi.fn().mockRejectedValue(options.createError)
     : vi.fn().mockImplementation(async (args: Record<string, unknown> = {}) => {
@@ -705,6 +709,7 @@ function resetChatTestStore() {
     workViewByProject: {},
     laneWorkViewByScope: {},
     draftLaunchJobsByScope: {},
+    handoffLaunchJobsByScope: {},
   });
 }
 
@@ -3070,7 +3075,48 @@ describe("AgentChatPane submit recovery", () => {
         cursorModeId: "agent",
         cursorConfigValues: {},
       }));
-      expect(onSessionCreated).toHaveBeenCalledWith(expect.objectContaining({ id: "session-2" }));
+      expect(onSessionCreated).toHaveBeenCalledWith(expect.objectContaining({ id: "session-2" }), { source: "handoff" });
+    });
+  });
+
+  it("tracks an ephemeral sidebar handoff launch job while handoff is in flight", async () => {
+    const session = buildSession("session-1", { status: "idle" });
+    let resolveHandoff!: (result: { session: AgentChatSession; usedFallbackSummary: boolean }) => void;
+    const pendingHandoff = new Promise<{ session: AgentChatSession; usedFallbackSummary: boolean }>((resolve) => {
+      resolveHandoff = resolve;
+    });
+    installAdeMocks({
+      handoffResult: pendingHandoff,
+    });
+
+    renderPane(session);
+
+    fireEvent.click(await screen.findByRole("button", { name: "Open chat actions drawer" }));
+    fireEvent.click(await screen.findByRole("button", { name: "Handoff" }));
+    fireEvent.click(await screen.findByRole("button", { name: "Create handoff chat" }));
+
+    await waitFor(() => {
+      const jobs = Object.values(useAppStore.getState().handoffLaunchJobsByScope).flat();
+      expect(jobs).toHaveLength(1);
+      expect(jobs[0]).toEqual(expect.objectContaining({
+        sourceSessionId: session.sessionId,
+        laneId: session.laneId,
+        targetModelLabel: "GPT-5.4-Mini",
+        targetToolType: "codex-chat",
+        status: "preparing-summary",
+      }));
+    });
+
+    await act(async () => {
+      resolveHandoff({
+        session: buildCreatedSession("session-2"),
+        usedFallbackSummary: false,
+      });
+      await pendingHandoff;
+    });
+
+    await waitFor(() => {
+      expect(Object.values(useAppStore.getState().handoffLaunchJobsByScope).flat()).toHaveLength(0);
     });
   });
 

apps/desktop/src/renderer/components/chat/AgentChatPane.tsx

@@ -171,6 +171,12 @@ import {
   type NativeControlState,
   type PreparedDraftLaunch,
 } from "../../lib/draftLaunchJobs";
+import {
+  buildHandoffLaunchJobsScopeKey,
+  createHandoffLaunchJobId,
+  type HandoffLaunchJob,
+  type HandoffLaunchJobStatus,
+} from "../../lib/handoffLaunchJobs";
 import {
   createAppControlContextInstanceId,
   createBuiltInBrowserContextInstanceId,
@@ -2924,6 +2930,15 @@ export function AgentChatPane({
   ) => {
     rootAppStoreApi.getState().setDraftLaunchJobs(draftLaunchJobsScopeKey, next);
   }, [draftLaunchJobsScopeKey]);
+  const handoffLaunchJobsScopeKey = useMemo(
+    () => buildHandoffLaunchJobsScopeKey({ projectBinding, projectRoot }),
+    [projectBinding, projectRoot],
+  );
+  const setHandoffLaunchJobs = useCallback((
+    next: HandoffLaunchJob[] | ((prev: HandoffLaunchJob[]) => HandoffLaunchJob[]),
+  ) => {
+    rootAppStoreApi.getState().setHandoffLaunchJobs(handoffLaunchJobsScopeKey, next);
+  }, [handoffLaunchJobsScopeKey]);
   const hasActiveDraftLaunchJobs = useMemo(
     () => draftLaunchJobs.some((job) => !isDraftLaunchJobTerminal(job.status)),
     [draftLaunchJobs],
@@ -3033,6 +3048,7 @@ export function AgentChatPane({
   const [loading, setLoading] = useState(false);
   const [preferencesReady, setPreferencesReady] = useState(false);
   const [error, setError] = useState<string | null>(null);
+  const handoffErrorClearTimerRef = useRef<number | null>(null);
   const [deletingChatSessionId, setDeletingChatSessionId] = useState<string | null>(null);
   const [computerUseSnapshot, setComputerUseSnapshot] = useState<ComputerUseOwnerSnapshot | null>(null);
   const [chatActionsOpen, setChatActionsOpen] = useState(
@@ -3064,6 +3080,12 @@ export function AgentChatPane({
     });
     return () => { cancelled = true; unsubscribe(); };
   }, [laneId]);
+  useEffect(() => () => {
+    if (handoffErrorClearTimerRef.current != null) {
+      window.clearTimeout(handoffErrorClearTimerRef.current);
+      handoffErrorClearTimerRef.current = null;
+    }
+  }, []);
   const [chatActionsTab, setChatActionsTab] = useState<ChatActionsTab>(
     () => readChatCompanionUiState(initialCompanionStateKey).chatActionsTab,
   );
@@ -7465,8 +7487,36 @@ export function AgentChatPane({
 
   const handoffSession = useCallback(async (mode: "brief" | "fork" = "brief") => {
     if (!canShowHandoff || !selectedSessionId || !handoffModelId || handoffBlocked) return;
+    const sourceLaneId = selectedSession?.laneId ?? laneId;
+    if (!sourceLaneId) return;
+    const jobId = createHandoffLaunchJobId();
+    const stageTimerIds: number[] = [];
+    const patchHandoffJob = (status: HandoffLaunchJobStatus) => {
+      setHandoffLaunchJobs((current) => current.map((job) => (
+        job.id === jobId ? { ...job, status } : job
+      )));
+    };
+    const targetModelLabel = handoffTargetDescriptor?.displayName
+      ?? formatLocalModelLabel(handoffModelId);
+    setHandoffLaunchJobs((current) => [
+      {
+        id: jobId,
+        sourceSessionId: selectedSessionId,
+        laneId: sourceLaneId,
+        laneName: laneDisplayLabel ?? sourceLaneId,
+        targetModelId: handoffModelId,
+        targetModelLabel,
+        targetToolType: handoffTargetProvider ? chatToolTypeForProvider(handoffTargetProvider) : "other",
+        status: "preparing-summary",
+        createdAtMs: Date.now(),
+      },
+      ...current.filter((job) => job.sourceSessionId !== selectedSessionId),
+    ]);
     setError(null);
     setHandoffBusy(true);
+    setChatActionsOpen(false);
+    stageTimerIds.push(window.setTimeout(() => patchHandoffJob("creating-chat"), 700));
+    stageTimerIds.push(window.setTimeout(() => patchHandoffJob("sending-handoff"), 1500));
     try {
       const resolvedHandoffPermissionMode = handoffNativePermissionMode ?? selectedSession?.permissionMode;
       const result = await window.ade.agentChat.handoff({
@@ -7487,13 +7537,22 @@ export function AgentChatPane({
         cursorModeId: handoffCursorModeId,
         cursorConfigValues: handoffCursorConfigValues,
       });
-      setChatActionsOpen(false);
-      notifySessionCreated(result.session);
+      notifySessionCreated(result.session, { source: "handoff" });
       invalidateCurrentChatSessionList();
       void refreshSessions({ force: true }).catch(() => {});
     } catch (handoffError) {
-      setError(handoffError instanceof Error ? handoffError.message : String(handoffError));
+      const message = handoffError instanceof Error ? handoffError.message : String(handoffError);
+      setError(message);
+      if (handoffErrorClearTimerRef.current != null) {
+        window.clearTimeout(handoffErrorClearTimerRef.current);
+      }
+      handoffErrorClearTimerRef.current = window.setTimeout(() => {
+        handoffErrorClearTimerRef.current = null;
+        setError((current) => (current === message ? null : current));
+      }, 6000);
     } finally {
+      stageTimerIds.forEach((timerId) => window.clearTimeout(timerId));
+      setHandoffLaunchJobs((current) => current.filter((job) => job.id !== jobId));
       setHandoffBusy(false);
     }
   }, [
@@ -7502,6 +7561,7 @@ export function AgentChatPane({
     handoffClaudePermissionMode,
     handoffCodexApprovalPolicy,
     handoffCodexConfigSource,
+    handoffTargetDescriptor,
     handoffFastMode,
     handoffCodexSandbox,
     handoffCursorConfigValues,
@@ -7513,10 +7573,14 @@ export function AgentChatPane({
     handoffReasoningEffort,
     handoffTargetProvider,
     invalidateCurrentChatSessionList,
+    laneDisplayLabel,
+    laneId,
     notifySessionCreated,
     refreshSessions,
     selectedSession?.permissionMode,
+    selectedSession?.laneId,
     selectedSessionId,
+    setHandoffLaunchJobs,
   ]);
 
   const handleDeleteSelectedChat = useCallback(() => {

apps/desktop/src/renderer/components/chat/chatUserMinimap.logic.test.ts

@@ -64,6 +64,38 @@ describe("chatUserMinimap.logic", () => {
     expect(entries.map((e) => e.fullUserOrdinal)).toEqual([0, 1]);
   });
 
+  it("uses display text for hidden handoff prompts and skips empty hidden prompts", () => {
+    const rows: ChatTranscriptGroupedEnvelope[] = [
+      {
+        key: "handoff-display",
+        timestamp: "2026-01-01T00:00:00.000Z",
+        event: {
+          type: "user_message",
+          text: "Internal handoff prompt that should not appear in the minimap.",
+          displayText: "Chat handoff from previous session",
+          metadata: { kind: "handoff", hideFullPrompt: true },
+        },
+      },
+      {
+        key: "handoff-hidden",
+        timestamp: "2026-01-01T00:00:01.000Z",
+        event: {
+          type: "user_message",
+          text: "Internal handoff prompt without display text.",
+          metadata: { kind: "handoff", hideFullPrompt: true },
+        },
+      },
+      userRow("normal prompt", "normal"),
+    ];
+
+    const entries = collectUserMessageMinimapSourceEntries(rows);
+
+    expect(entries.map((entry) => entry.preview)).toEqual([
+      "Chat handoff from previous session",
+      "normal prompt",
+    ]);
+  });
+
   it("samples when above max markers", () => {
     const entries = Array.from({ length: 100 }, (_, i) => ({
       rowIndex: i,

apps/desktop/src/renderer/components/chat/chatUserMinimap.logic.ts

@@ -46,7 +46,10 @@ export function collectUserMessageMinimapSourceEntries(
     const row = groupedRows[rowIndex]!;
     if (!isTimelineUserMessageRow(row)) continue;
     const event = row.event;
-    const preview = summarizeInlineText(event.text ?? "", PREVIEW_MAX_CHARS);
+    const hideFullPrompt = event.metadata?.hideFullPrompt === true;
+    const previewSource = hideFullPrompt ? (event.displayText?.trim() ?? "") : (event.text ?? "");
+    const preview = summarizeInlineText(previewSource, PREVIEW_MAX_CHARS);
+    if (hideFullPrompt && preview.length === 0) continue;
     out.push({
       rowIndex,
       key: row.key,

apps/desktop/src/renderer/components/terminals/SessionListPane.test.tsx

@@ -110,6 +110,31 @@ describe("SessionListPane", () => {
     expect(screen.getByText("Mobile Tool Streaming UI")).toBeTruthy();
   });
 
+  it("renders in-flight handoff placeholders in the matching lane group", () => {
+    renderPane({
+      runningFiltered: [],
+      sessionsGroupedByLane: new Map(),
+      handoffJobs: [
+        {
+          id: "handoff-job-1",
+          sourceSessionId: "source-session",
+          laneId: "lane-known",
+          laneName: "Known Lane",
+          targetModelId: "openai/gpt-5.4-mini",
+          targetModelLabel: "GPT-5.4-Mini",
+          targetToolType: "codex-chat",
+          status: "creating-chat",
+          createdAtMs: Date.now(),
+        },
+      ],
+    });
+
+    expect(screen.getByTestId("handoff-launch-placeholder")).toBeTruthy();
+    expect(screen.getByText("Handoff to GPT-5.4-Mini")).toBeTruthy();
+    expect(screen.getByText("Creating chat...")).toBeTruthy();
+    expect(screen.getByText("First message: Chat handoff from previous session")).toBeTruthy();
+  });
+
   it("lets the user set the group organization from the filter panel", () => {
     const setSessionListOrganization = vi.fn();
     const view = renderPane({ setSessionListOrganization });