diff --git a/heartbeats/plan-git-harden-sh-design-spec-2153.json b/heartbeats/plan-git-harden-sh-design-spec-2153.json
new file mode 100644
index 0000000..e920718
--- /dev/null
+++ b/heartbeats/plan-git-harden-sh-design-spec-2153.json
@@ -0,0 +1,6 @@
+{
+  "agent_id": "plan-git-harden-sh-design-spec-2153",
+  "last_heartbeat": "2026-03-27T16:44:58.647852Z",
+  "active_issue_id": null,
+  "machine_id": "MacBook-Air-4.local"
+}
\ No newline at end of file