diff --git a/src/workspaces/officerdev/src/apps/Chat/background-job-prompt.ts b/src/workspaces/officerdev/src/apps/Chat/background-job-prompt.ts
index 2e0c5009..59182667 100644
--- a/src/workspaces/officerdev/src/apps/Chat/background-job-prompt.ts
+++ b/src/workspaces/officerdev/src/apps/Chat/background-job-prompt.ts
@@ -120,5 +120,14 @@ export function buildBackgroundJobPrompt(spec: BackgroundJobSpec): string {
     `Do not read the output back to check it started. If it fails, the exit reaches me on its own —`,
     `that is the entire point of using the harness's mechanism, and checking by hand just adds noise`,
     `to the one case where nothing is wrong.`,
+    ``,
+    `IF IT EXITS:`,
+    ``,
+    `Say so in one line and STOP. Do not restart it. Do not diagnose why. Do not theorise about what`,
+    `else on the machine might have touched it.`,
+    ``,
+    `I can stop a job myself, from a button on its chip — so an exit is at least as likely to be me`,
+    `as it is to be a failure, and a job I stopped that comes back on its own is the opposite of a`,
+    `stop button. If I want it running again I will start it again.`,
   ].join('\n');
 }
diff --git a/src/workspaces/officerdev/src/apps/Chat/components/BackgroundTaskTray.tsx b/src/workspaces/officerdev/src/apps/Chat/components/BackgroundTaskTray.tsx
index 79caa898..6b12b9d8 100644
--- a/src/workspaces/officerdev/src/apps/Chat/components/BackgroundTaskTray.tsx
+++ b/src/workspaces/officerdev/src/apps/Chat/components/BackgroundTaskTray.tsx
@@ -71,7 +71,13 @@ export const BackgroundTaskTray = ({ messages }: BackgroundTaskTrayProps) => {
 
   return (
     <div className="mb-2 rounded-lg border border-border bg-muted/40">
-      {open && <TaskPanel task={open} onClose={() => setOpenId(null)} />}
+      {open && (
+        <TaskPanel
+          task={open}
+          onClose={() => setOpenId(null)}
+          onStop={open.status ? undefined : () => void stopTask(open.taskId)}
+        />
+      )}
 
       {pinned.length > 0 && (
         <TaskStrip label="Pinned" divided={unpinned.length > 0}>
@@ -222,11 +228,13 @@ const TaskChip = ({ task, active, pinned, onClick, onTogglePin, onDismiss, onSto
 // ── Panel ──
 
 type TaskPanelProps = {
+  /** Present only while the task is running — the panel shows a real button rather than a bare glyph. */
+  onStop?: () => void;
   task: BackgroundTask;
   onClose: () => void;
 };
 
-const TaskPanel = ({ task, onClose }: TaskPanelProps) => {
+const TaskPanel = ({ task, onClose, onStop }: TaskPanelProps) => {
   const running = !task.status;
   const { data, isLoading } = useTaskDetail(task.taskId, running);
   const bodyRef = useRef<HTMLDivElement | null>(null);
@@ -249,6 +257,20 @@ const TaskPanel = ({ task, onClose }: TaskPanelProps) => {
           </div>
         </div>
         {running && <Loader2 className="h-3.5 w-3.5 shrink-0 animate-spin text-warning" />}
+        {/* Labelled here, unlike the chip's icon-only version. The panel is where you come to decide
+            whether to keep something running, so the control that ends it should not be a glyph you
+            have to hover to identify. */}
+        {running && onStop && (
+          <button
+            type="button"
+            onClick={onStop}
+            title="Stop this job"
+            className="flex shrink-0 cursor-pointer items-center gap-1 rounded border border-border px-2 py-1 text-xs text-muted-foreground transition-colors hover:border-destructive/40 hover:text-destructive"
+          >
+            <Square className="h-3 w-3" />
+            Stop
+          </button>
+        )}
         <button
           type="button"
           onClick={onClose}