diff --git a/apps/web/src/commandPaletteStore.test.ts b/apps/web/src/commandPaletteStore.test.ts
new file mode 100644
index 000000000..917217bbc
--- /dev/null
+++ b/apps/web/src/commandPaletteStore.test.ts
@@ -0,0 +1,57 @@
+import { beforeEach, describe, expect, it } from "vite-plus/test";
+
+import { useCommandPaletteStore } from "./commandPaletteStore";
+
+function resetStore(): void {
+  useCommandPaletteStore.setState({ open: false, openGeneration: 0, openIntent: null });
+}
+
+describe("command palette store", () => {
+  beforeEach(resetStore);
+
+  it("advances the open generation once per opening, not per open call", () => {
+    const { setOpen, openAddProject } = useCommandPaletteStore.getState();
+
+    setOpen(true);
+    expect(useCommandPaletteStore.getState().openGeneration).toBe(1);
+
+    // Re-purposing an already-open palette stays in the same session.
+    setOpen(true);
+    openAddProject();
+    expect(useCommandPaletteStore.getState().openGeneration).toBe(1);
+
+    setOpen(false);
+    setOpen(true);
+    expect(useCommandPaletteStore.getState().openGeneration).toBe(2);
+  });
+
+  it("closes via closeIfGeneration only for the current session", () => {
+    const { setOpen, closeIfGeneration } = useCommandPaletteStore.getState();
+
+    setOpen(true);
+    const firstSession = useCommandPaletteStore.getState().openGeneration;
+    setOpen(false);
+    setOpen(true);
+
+    // A continuation from the first session must not close the second.
+    closeIfGeneration(firstSession);
+    expect(useCommandPaletteStore.getState().open).toBe(true);
+
+    closeIfGeneration(useCommandPaletteStore.getState().openGeneration);
+    expect(useCommandPaletteStore.getState().open).toBe(false);
+
+    // Already closed: a repeat stale close stays a no-op.
+    closeIfGeneration(firstSession);
+    expect(useCommandPaletteStore.getState().open).toBe(false);
+  });
+
+  it("clears the open intent when a guarded close lands", () => {
+    const { openAddProject, closeIfGeneration } = useCommandPaletteStore.getState();
+
+    openAddProject();
+    expect(useCommandPaletteStore.getState().openIntent?.kind).toBe("add-project");
+
+    closeIfGeneration(useCommandPaletteStore.getState().openGeneration);
+    expect(useCommandPaletteStore.getState().openIntent).toBeNull();
+  });
+});
diff --git a/apps/web/src/commandPaletteStore.ts b/apps/web/src/commandPaletteStore.ts
index 9bff87b53..5d07a961b 100644
--- a/apps/web/src/commandPaletteStore.ts
+++ b/apps/web/src/commandPaletteStore.ts
@@ -13,8 +13,18 @@ type CommandPaletteOpenIntent =
 
 interface CommandPaletteStore {
   open: boolean;
+  /**
+   * Increments on every opening. Async flows that close the palette after an
+   * await must capture this when they start and close via `closeIfGeneration`,
+   * so a continuation that outlives its own palette session (the user closed
+   * or reopened it while the request was in flight) cannot slam a palette it
+   * does not own.
+   */
+  openGeneration: number;
   openIntent: CommandPaletteOpenIntent | null;
   setOpen: (open: boolean) => void;
+  /** Closes only if the palette is still on the given open generation. */
+  closeIfGeneration: (generation: number) => void;
   toggleOpen: () => void;
   openAddProject: () => void;
   openThreadSearch: (request: CommandPaletteThreadSearchRequest) => void;
@@ -23,13 +33,30 @@ interface CommandPaletteStore {
 
 export const useCommandPaletteStore = create<CommandPaletteStore>((set) => ({
   open: false,
+  openGeneration: 0,
   openIntent: null,
-  setOpen: (open) => set({ open, ...(open ? {} : { openIntent: null }) }),
+  setOpen: (open) =>
+    set((state) => ({
+      open,
+      ...(open
+        ? state.open
+          ? {}
+          : { openGeneration: state.openGeneration + 1 }
+        : { openIntent: null }),
+    })),
+  closeIfGeneration: (generation) =>
+    set((state) =>
+      state.open && state.openGeneration === generation ? { open: false, openIntent: null } : state,
+    ),
   toggleOpen: () =>
-    set((state) => ({ open: !state.open, ...(state.open ? { openIntent: null } : {}) })),
+    set((state) => ({
+      open: !state.open,
+      ...(state.open ? { openIntent: null } : { openGeneration: state.openGeneration + 1 }),
+    })),
   openAddProject: () =>
     set((state) => ({
       open: true,
+      ...(state.open ? {} : { openGeneration: state.openGeneration + 1 }),
       openIntent: {
         kind: "add-project",
         requestId: (state.openIntent?.requestId ?? 0) + 1,
@@ -38,6 +65,7 @@ export const useCommandPaletteStore = create<CommandPaletteStore>((set) => ({
   openThreadSearch: (request) =>
     set((state) => ({
       open: true,
+      ...(state.open ? {} : { openGeneration: state.openGeneration + 1 }),
       openIntent: {
         kind: "search-threads",
         requestId: (state.openIntent?.requestId ?? 0) + 1,
diff --git a/apps/web/src/components/CommandPalette.tsx b/apps/web/src/components/CommandPalette.tsx
index 5fefbbc97..ef4d1a56b 100644
--- a/apps/web/src/components/CommandPalette.tsx
+++ b/apps/web/src/components/CommandPalette.tsx
@@ -445,13 +445,6 @@ export function CommandPalette({ children }: { children: ReactNode }) {
 
 function CommandPaletteDialog() {
   const open = useCommandPaletteStore((store) => store.open);
-  const setOpen = useCommandPaletteStore((store) => store.setOpen);
-
-  useEffect(() => {
-    return () => {
-      setOpen(false);
-    };
-  }, [setOpen]);
 
   if (!open) {
     return null;
@@ -463,9 +456,23 @@ function CommandPaletteDialog() {
 function OpenCommandPaletteDialog() {
   const navigate = useNavigate();
   const setOpen = useCommandPaletteStore((store) => store.setOpen);
+  const closeIfGeneration = useCommandPaletteStore((store) => store.closeIfGeneration);
   const openIntent = useCommandPaletteStore((store) => store.openIntent);
   const clearOpenIntent = useCommandPaletteStore((store) => store.clearOpenIntent);
   const composerHandleRef = useComposerHandleContext();
+  // This component mounts once per palette session, so its mount-time
+  // generation identifies the session every deferred close below belongs to.
+  // Async flows and the unmount reset close via `closeIfGeneration`: if the
+  // user closed or reopened the palette while a request was in flight (or
+  // React deferred the unmount cleanup past a new session), the stale close
+  // is a no-op instead of slamming a palette it does not own.
+  const [sessionGeneration] = useState(() => useCommandPaletteStore.getState().openGeneration);
+
+  useEffect(() => {
+    return () => {
+      closeIfGeneration(sessionGeneration);
+    };
+  }, [closeIfGeneration, sessionGeneration]);
   const [query, setQuery] = useState("");
   const deferredQuery = useDeferredValue(query);
   const isActionsOnly = deferredQuery.startsWith(">");
@@ -1413,7 +1420,7 @@ function OpenCommandPaletteDialog() {
           runtimeMode:
             activeThread?.runtimeMode ?? activeDraftThread?.runtimeMode ?? DEFAULT_RUNTIME_MODE,
         });
-        setOpen(false);
+        closeIfGeneration(sessionGeneration);
         await navigate({
           to: "/$environmentId/$threadId",
           params: buildThreadRouteParams(
@@ -1428,11 +1435,12 @@ function OpenCommandPaletteDialog() {
       activeDraftThread?.runtimeMode,
       activeThread?.runtimeMode,
       codexSessionFlow,
+      closeIfGeneration,
       currentEnvironmentProviders,
       currentEnvironmentSettings,
       importingProviderThreadId,
       navigate,
-      setOpen,
+      sessionGeneration,
     ],
   );
 
@@ -1691,7 +1699,7 @@ function OpenCommandPaletteDialog() {
             envMode: settings.defaultThreadEnvMode,
           }).catch(() => undefined);
         }
-        setOpen(false);
+        closeIfGeneration(sessionGeneration);
         return;
       }
 
@@ -1717,7 +1725,7 @@ function OpenCommandPaletteDialog() {
         await handleNewThread(createdProjectRef, {
           envMode: settings.defaultThreadEnvMode,
         }).catch(() => undefined);
-        setOpen(false);
+        closeIfGeneration(sessionGeneration);
       } catch (error) {
         toastManager.add(
           stackedThreadToast({
@@ -1731,11 +1739,12 @@ function OpenCommandPaletteDialog() {
     [
       browseEnvironmentId,
       browseEnvironmentPlatform,
+      closeIfGeneration,
       currentProjectCwdForBrowse,
       handleNewThread,
       navigate,
       projects,
-      setOpen,
+      sessionGeneration,
       settings.defaultThreadEnvMode,
       settings.sidebarThreadSortOrder,
       threads,