fix: preserve authoritative archived task state (#1826)

apps/web/components/task/task-page-content-helpers.test.ts

@@ -1,5 +1,10 @@
 import { describe, expect, it, vi } from "vitest";
-import type { Task } from "@/lib/types/http";
+import {
+  taskId as toTaskId,
+  workflowId as toWorkflowId,
+  workspaceId as toWorkspaceId,
+  type Task,
+} from "@/lib/types/http";
 import type { KanbanState } from "@/lib/state/slices";
 import {
   buildArchivedValue,
@@ -12,6 +17,7 @@ import {
 } from "./task-page-content-helpers";
 
 type KanbanTask = KanbanState["tasks"][number];
+const ARCHIVED_AT = "2026-07-19T00:00:00Z";
 
 function makeArchivedTaskDetails(overrides: Partial<Task> = {}): Task {
   return {
@@ -26,8 +32,8 @@ function makeArchivedTaskDetails(overrides: Partial<Task> = {}): Task {
     priority: 0,
     repositories: [],
     created_at: "",
-    updated_at: "2026-07-19T00:00:00Z",
-    archived_at: "2026-07-19T00:00:00Z",
+    updated_at: ARCHIVED_AT,
+    archived_at: ARCHIVED_AT,
     ...overrides,
   } as Task;
 }
@@ -222,15 +228,19 @@ describe("syncActiveTaskSession", () => {
 });
 
 describe("resolveEffectiveTask archived state", () => {
-  // Regression: unarchiving from the detail top bar publishes
-  // task.updated(archived_at=null) which re-adds the task to the kanban, but
-  // the one-shot fetchTask details still carry the old archived_at. The
-  // resolved task must reflect the live kanban entry so the top bar stops
-  // showing the archived UI / Unarchive button — otherwise the task "never
-  // comes back" after a successful unarchive.
-  it("clears a stale archived_at when the task is present in the kanban", () => {
+  it("keeps fetched archived state when a stale matching kanban card remains", () => {
     const taskDetails = makeArchivedTaskDetails();
-    const kanbanTask = makeKanbanTask();
+    const kanbanTask = makeKanbanTask({ updatedAt: "2026-07-18T00:00:00Z" });
+
+    const resolved = resolveEffectiveTask(taskDetails, null, kanbanTask, "task-1");
+
+    expect(resolved?.archived_at).toBe(ARCHIVED_AT);
+    expect(buildArchivedValue(resolved, null).isArchived).toBe(true);
+  });
+
+  it("clears fetched archived state when a matching kanban card is newer", () => {
+    const taskDetails = makeArchivedTaskDetails();
+    const kanbanTask = makeKanbanTask({ updatedAt: "2026-07-20T00:00:00Z" });
 
     const resolved = resolveEffectiveTask(taskDetails, null, kanbanTask, "task-1");
 
@@ -243,7 +253,7 @@ describe("resolveEffectiveTask archived state", () => {
 
     const resolved = resolveEffectiveTask(taskDetails, null, null, "task-1");
 
-    expect(resolved?.archived_at).toBe("2026-07-19T00:00:00Z");
+    expect(resolved?.archived_at).toBe(ARCHIVED_AT);
     expect(buildArchivedValue(resolved, null).isArchived).toBe(true);
   });
 
@@ -257,4 +267,18 @@ describe("resolveEffectiveTask archived state", () => {
     expect(resolved?.state).toBe("IN_PROGRESS");
     expect(resolved?.workspace_id).toBe("ws-1");
   });
+
+  it("does not copy IDs from rejected task details into a kanban-only placeholder", () => {
+    const unrelatedTask = makeArchivedTaskDetails({
+      id: toTaskId("other-task"),
+      workspace_id: toWorkspaceId("other-workspace"),
+      workflow_id: toWorkflowId("other-workflow"),
+    });
+    const kanbanTask = makeKanbanTask({ id: toTaskId("task-1") });
+
+    const resolved = resolveEffectiveTask(unrelatedTask, null, kanbanTask, "task-1");
+
+    expect(resolved?.workspace_id).toBe("");
+    expect(resolved?.workflow_id).toBe("");
+  });
 });

apps/web/components/task/task-page-content-helpers.ts

@@ -118,7 +118,7 @@ export function resolveEffectiveTask(
 
   if (!baseTask && !kanbanTask) return null;
   if (baseTask) return mergeBaseWithKanban(baseTask, kanbanTask);
-  if (kanbanTask) return buildTaskFromKanban(kanbanTask, taskDetails, initialTask);
+  if (kanbanTask) return buildTaskFromKanban(kanbanTask);
   return null;
 }
 
@@ -127,6 +127,13 @@ export function mergeBaseWithKanban(
   kanbanTask: KanbanState["tasks"][number] | null,
 ): Task {
   if (!kanbanTask) return baseTask;
+  const kanbanUpdatedAt = Date.parse(kanbanTask.updatedAt ?? "");
+  const baseUpdatedAt = Date.parse(baseTask.updated_at ?? "");
+  const hasNewerKanbanState =
+    Boolean(baseTask.archived_at) &&
+    Number.isFinite(kanbanUpdatedAt) &&
+    Number.isFinite(baseUpdatedAt) &&
+    kanbanUpdatedAt > baseUpdatedAt;
   return {
     ...baseTask,
     title: kanbanTask.title ?? baseTask.title,
@@ -136,25 +143,11 @@ export function mergeBaseWithKanban(
     position: kanbanTask.position ?? baseTask.position,
     state: (kanbanTask.state as Task["state"] | undefined) ?? baseTask.state,
     repositories: baseTask.repositories,
-    // A task present in the kanban board is by definition not archived: the
-    // board never holds archived tasks, and unarchive re-adds it via
-    // task.updated(archived_at=null). The one-shot `fetchTask` that seeds
-    // baseTask only refetches on task-id change, so it keeps a stale
-    // archived_at after an in-place unarchive from the detail top bar —
-    // trust the live kanban entry instead. Without this the top bar keeps
-    // showing the Unarchive button / archived banner and the task "never
-    // comes back" even though the backend restored it.
-    archived_at: null,
+    archived_at: hasNewerKanbanState ? null : baseTask.archived_at,
   };
 }
 
-export function buildTaskFromKanban(
-  kanbanTask: KanbanState["tasks"][number],
-  taskDetails: Task | null,
-  initialTask: Task | null,
-): Task {
-  const prevWorkspaceId = taskDetails?.workspace_id ?? initialTask?.workspace_id;
-  const prevBoardId = taskDetails?.workflow_id ?? initialTask?.workflow_id;
+export function buildTaskFromKanban(kanbanTask: KanbanState["tasks"][number]): Task {
   return {
     id: toTaskId(kanbanTask.id),
     title: kanbanTask.title,
@@ -162,8 +155,8 @@ export function buildTaskFromKanban(
     workflow_step_id: kanbanTask.workflowStepId,
     position: kanbanTask.position,
     state: kanbanTask.state ?? "CREATED",
-    workspace_id: prevWorkspaceId ?? toWorkspaceId(""),
-    workflow_id: prevBoardId ?? toWorkflowId(""),
+    workspace_id: toWorkspaceId(""),
+    workflow_id: toWorkflowId(""),
     priority: 0,
     repositories: [],
     created_at: "",

apps/web/components/task/task-page-content.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useEffect, useMemo, useState } from "react";
+import { useCallback, useEffect, useMemo, useState } from "react";
 import { IconAlertTriangle } from "@tabler/icons-react";
 import type { Repository, RepositoryScript, Task } from "@/lib/types/http";
 import type { Terminal } from "@/hooks/domains/session/use-terminals";
@@ -217,7 +217,18 @@ function useTaskDetails(activeTaskId: string | null, initialTask: Task | null) {
     setTaskDetails,
   ]);
 
-  return { task, kanbanTask, taskLoadError: hasTaskDetails ? null : taskLoadError };
+  const onTaskUnarchived = useCallback((taskId: string) => {
+    setTaskDetails((current) =>
+      current?.id === taskId ? { ...current, archived_at: null } : current,
+    );
+  }, []);
+
+  return {
+    task,
+    kanbanTask,
+    taskLoadError: hasTaskDetails ? null : taskLoadError,
+    onTaskUnarchived,
+  };
 }
 
 function useTaskPageData(
@@ -239,7 +250,7 @@ function useTaskPageData(
     return session?.task_id === activeTaskId ? sid : null;
   });
 
-  const { task, taskLoadError } = useTaskDetails(activeTaskId, initialTask);
+  const { task, taskLoadError, onTaskUnarchived } = useTaskDetails(activeTaskId, initialTask);
 
   const agent = useSessionAgent(task);
   const ensureSession = useEnsureTaskSession(task);
@@ -266,7 +277,15 @@ function useTaskPageData(
     [effectiveRepositories, task?.repositories],
   );
 
-  return { task, taskLoadError, agent, effectiveSessionId, repository, ensureSession };
+  return {
+    task,
+    taskLoadError,
+    agent,
+    effectiveSessionId,
+    repository,
+    ensureSession,
+    onTaskUnarchived,
+  };
 }
 
 export function TaskPageContent({
@@ -285,8 +304,15 @@ export function TaskPageContent({
   const { isMobile } = useResponsiveBreakpoint();
   const connectionStatus = useAppStore((state) => state.connection.status);
 
-  const { task, taskLoadError, agent, effectiveSessionId, repository, ensureSession } =
-    useTaskPageData(initialTask, initialTaskId, sessionId, initialRepositories);
+  const {
+    task,
+    taskLoadError,
+    agent,
+    effectiveSessionId,
+    repository,
+    ensureSession,
+    onTaskUnarchived,
+  } = useTaskPageData(initialTask, initialTaskId, sessionId, initialRepositories);
 
   const workflowSteps = useWorkflowStepsMapped();
   const sessionPanel = useSessionPanelState(effectiveSessionId);
@@ -334,6 +360,7 @@ export function TaskPageContent({
       initialLayout={initialLayout}
       officeTaskHref={officeTaskHref}
       ensureSession={ensureSession}
+      onTaskUnarchived={onTaskUnarchived}
     />
   );
 }

apps/web/components/task/task-page-inner.tsx

@@ -50,6 +50,7 @@ export type TaskPageInnerProps = {
   initialLayout?: string | null;
   officeTaskHref?: string | null;
   ensureSession: UseEnsureTaskSessionResult;
+  onTaskUnarchived: (taskId: string) => void;
 };
 
 type RemoteExecutorStatus = {
@@ -100,6 +101,7 @@ function buildTaskTopBarProps(params: {
   sessionWorkflowStepId: string | null;
   agentctlReady: boolean;
   officeTaskHref?: string | null;
+  onTaskUnarchived: (taskId: string) => void;
 }) {
   const { taskProps, agent, merged, workflowSteps, showDebugOverlay, onToggleDebugOverlay } =
     params;
@@ -124,6 +126,7 @@ function buildTaskTopBarProps(params: {
     isAgentctlReady: params.agentctlReady,
     remoteExecutorType: params.remote.remoteExecutorType,
     officeTaskHref: params.officeTaskHref,
+    onTaskUnarchived: params.onTaskUnarchived,
   };
 }
 
@@ -212,6 +215,7 @@ export function TaskPageInner({
   initialLayout,
   officeTaskHref,
   ensureSession,
+  onTaskUnarchived,
 }: TaskPageInnerProps) {
   const taskProps = resolveTaskProps(task, repository);
   const remote = resolveRemoteExecutor(resumption.sessionStatus as RemoteExecutorStatus | null);
@@ -241,6 +245,7 @@ export function TaskPageInner({
     sessionWorkflowStepId: sessionPanel.sessionWorkflowStepId,
     agentctlReady: agentctlStatus.isReady,
     officeTaskHref,
+    onTaskUnarchived,
   });
   const layoutProps = buildTaskLayoutProps({
     taskProps,

apps/web/components/task/task-top-bar.tsx

@@ -43,6 +43,7 @@ type TaskTopBarProps = {
   isAgentctlReady?: boolean;
   remoteExecutorType?: string | null;
   officeTaskHref?: string | null;
+  onTaskUnarchived?: (taskId: string) => void;
 };
 
 type TopBarLeftProps = {
@@ -70,6 +71,7 @@ const TaskTopBar = memo(function TaskTopBar({
   issueNumber,
   remoteExecutorType,
   officeTaskHref,
+  onTaskUnarchived,
 }: TaskTopBarProps) {
   return (
     <header
@@ -107,6 +109,7 @@ const TaskTopBar = memo(function TaskTopBar({
         issueUrl={issueUrl}
         issueNumber={issueNumber}
         officeTaskHref={officeTaskHref}
+        onTaskUnarchived={onTaskUnarchived}
       />
     </header>
   );
@@ -336,6 +339,7 @@ function TopBarRight({
   issueUrl,
   issueNumber,
   officeTaskHref,
+  onTaskUnarchived,
 }: {
   taskId?: string | null;
   activeSessionId?: string | null;
@@ -349,13 +353,14 @@ function TopBarRight({
   issueUrl?: string;
   issueNumber?: number;
   officeTaskHref?: string | null;
+  onTaskUnarchived?: (taskId: string) => void;
 }) {
   return (
     <div className="flex items-center justify-self-end gap-2 [&_button]:whitespace-nowrap">
       <TopbarMetrics activeSessionId={activeSessionId} size="sm" />
       {isArchived && (
         <TopbarCluster label="Unarchive task" className="[&_button]:h-7 [&_button]:text-xs">
-          <TaskUnarchiveButton taskId={taskId} />
+          <TaskUnarchiveButton taskId={taskId} onUnarchived={onTaskUnarchived} />
         </TopbarCluster>
       )}
       {officeTaskHref && (

apps/web/components/task/task-unarchive-button.tsx

@@ -7,10 +7,13 @@ import { unarchiveTask } from "@/lib/api";
 import { unarchiveToastPayload } from "@/lib/tasks/unarchive-feedback";
 import { useToast } from "@/components/toast-provider";
 
-// Shown in the task top bar when the task is archived. On success the
-// backend publishes task.updated with archived_at=null, which restores the
-// task in the kanban/store — no manual refetch needed here.
-export function TaskUnarchiveButton({ taskId }: { taskId?: string | null }) {
+export function TaskUnarchiveButton({
+  taskId,
+  onUnarchived,
+}: {
+  taskId?: string | null;
+  onUnarchived?: (taskId: string) => void;
+}) {
   const { toast } = useToast();
   const [isPending, setIsPending] = useState(false);
   if (!taskId) return null;
@@ -20,6 +23,11 @@ export function TaskUnarchiveButton({ taskId }: { taskId?: string | null }) {
     try {
       const result = await unarchiveTask(taskId);
       toast(unarchiveToastPayload(result));
+      if (result.success && result.unarchived_ids.includes(taskId)) {
+        onUnarchived?.(taskId);
+      } else if (result.success) {
+        console.warn("[TaskUnarchiveButton] task missing from successful response", taskId);
+      }
     } catch (err) {
       toast({
         title: "Failed to unarchive task",

apps/web/e2e/tests/task/unarchive-detail-topbar.spec.ts

@@ -2,12 +2,8 @@ import { test, expect } from "../../fixtures/test-base";
 
 // Regression: unarchiving from the task-detail top bar must clear the archived
 // UI *in place*. The detail view seeds `archived_at` from a one-shot fetchTask
-// that only re-fetches when the task id changes. Unarchive publishes
-// task.updated(archived_at=null), which re-adds the task to the kanban, and the
-// task resolver must trust that live entry over the stale fetch. Before the fix
-// the merge kept the stale archived_at, so the Unarchive button stayed and the
-// task "never came back" even though the backend restored it and the toast said
-// success.
+// that only re-fetches when the task id changes, so the successful lifecycle
+// request must explicitly clear that local detail state.
 test("unarchiving from the detail top bar clears the archived UI in place", async ({
   testPage,
   apiClient,
@@ -35,5 +31,5 @@ test("unarchiving from the detail top bar clears the archived UI in place", asyn
   // proves the detail view observed the unarchive without a navigation/refetch.
   await expect(unarchiveButton).toHaveCount(0);
   // No redirect away — unarchive keeps the user on the same task route.
-  await expect(testPage).toHaveURL(new RegExp(`/t/${task.id}`));
+  await expect(testPage).toHaveURL((url) => url.pathname === `/t/${task.id}`);
 });

apps/web/lib/ws/handlers/tasks-unarchive.test.ts

@@ -56,11 +56,10 @@ function makeUpdatedMessage(payload: Record<string, unknown>) {
   } as Parameters<NonNullable<ReturnType<typeof registerTasksHandlers>["task.updated"]>>[0];
 }
 
-// Unarchive is delivered as task.updated with archived_at back to null. The
-// handler must re-add the task to the kanban caches (mirror of the archive
-// removal path).
+// The backend omits archived_at after unarchive because the field is nil. The
+// resulting task.updated event must still re-add the task to the kanban caches.
 describe("task.updated unarchive restore", () => {
-  it("re-adds the task to the active kanban when archived_at clears", () => {
+  it("re-adds the task to the active kanban when archived_at is omitted", () => {
     const store = makeStore();
     const handlers = registerTasksHandlers(store);
 
@@ -72,7 +71,6 @@ describe("task.updated unarchive restore", () => {
         title: "Restored task",
         state: "TODO",
         is_ephemeral: false,
-        archived_at: null,
       }),
     );
 
@@ -80,7 +78,7 @@ describe("task.updated unarchive restore", () => {
     expect(state.kanban.tasks.map((t) => t.id)).toContain(TASK_ID);
   });
 
-  it("re-adds the task to a multi-kanban snapshot when archived_at clears", () => {
+  it("re-adds the task to a multi-kanban snapshot when archived_at is omitted", () => {
     const store = makeStore({
       kanban: { workflowId: "wf-other", steps: [], tasks: [] } as unknown as AppState["kanban"],
       kanbanMulti: {
@@ -100,7 +98,6 @@ describe("task.updated unarchive restore", () => {
         title: "Restored task",
         state: "TODO",
         is_ephemeral: false,
-        archived_at: null,
       }),
     );