diff --git a/web/src/app/app/admin/_components/WorkerHealthAlert.tsx b/web/src/app/app/admin/_components/WorkerHealthAlert.tsx
new file mode 100644
index 00000000..6d9f5df8
--- /dev/null
+++ b/web/src/app/app/admin/_components/WorkerHealthAlert.tsx
@@ -0,0 +1,78 @@
+// Cross-page worker health banner. Renders at the top of every admin page
+// when any worker needs attention (errored, offline, or stuck mid-install).
+// Click the banner to jump into the workers list with the relevant filter
+// pre-applied.
+
+import { useMemo } from "react";
+import { useQuery } from "@tanstack/react-query";
+import { Link, useLocation } from "react-router-dom";
+import { listManagedWorkers } from "@/lib/api/client/app/admin/workers";
+
+const OFFLINE_MS = 5 * 60_000;
+
+export default function WorkerHealthAlert() {
+    const { pathname } = useLocation();
+    // Don't render on the workers list page itself — that page has its own
+    // richer banner with filter chips, no point doubling up.
+    const onWorkersPage = pathname.startsWith("/app/admin/workers");
+
+    const { data } = useQuery({
+        queryKey: ["admin", "workers", "managed"],
+        queryFn: listManagedWorkers,
+        refetchInterval: 30_000,
+        // Stale time covers fast nav between admin pages without re-fetching.
+        staleTime: 10_000,
+    });
+
+    const summary = useMemo(() => {
+        let errored = 0, offline = 0, inProgress = 0;
+        for (const w of data?.data ?? []) {
+            if (w.install_state === "error") {
+                errored++;
+                continue;
+            }
+            if (
+                w.install_state === "pending" ||
+                w.install_state === "provisioning" ||
+                w.install_state === "uninstalling"
+            ) {
+                inProgress++;
+                continue;
+            }
+            if (w.install_state !== "installed") continue;
+            const seenAge = w.last_seen_at ? Date.now() - new Date(w.last_seen_at).getTime() : Infinity;
+            if (seenAge > OFFLINE_MS) offline++;
+        }
+        return { errored, offline, inProgress, total: errored + offline + inProgress };
+    }, [data]);
+
+    if (onWorkersPage || summary.total === 0) return null;
+
+    // Pick the most urgent category first.
+    const tone = summary.errored > 0 || summary.offline > 0 ? "red" : "amber";
+    const toneCls = tone === "red"
+        ? "bg-red-50 border-red-300 text-red-800"
+        : "bg-amber-50 border-amber-300 text-amber-800";
+
+    const parts: string[] = [];
+    if (summary.errored > 0) parts.push(`${summary.errored} errored`);
+    if (summary.offline > 0) parts.push(`${summary.offline} offline`);
+    if (summary.inProgress > 0) parts.push(`${summary.inProgress} in progress`);
+
+    return (
+        <div className={`border rounded-lg px-3 py-2 mb-4 text-sm flex items-center justify-between ${toneCls}`}>
+            <div>
+                <span className="font-semibold">
+                    {summary.total} worker{summary.total === 1 ? "" : "s"} need attention
+                </span>
+                <span className="ml-2 opacity-80">— {parts.join(" · ")}</span>
+            </div>
+            <Link
+                to="/app/admin/workers"
+                className="text-xs font-medium underline hover:no-underline"
+            >
+                review →
+            </Link>
+        </div>
+    );
+}