diff --git a/trust/allowed_signers b/trust/allowed_signers
index b2551e0..f41ccec 100644
--- a/trust/allowed_signers
+++ b/trust/allowed_signers
@@ -2,3 +2,5 @@
 # Format: <principal> <key-type> <base64-key> [comment]
 # approved by flo at 2026-03-27 16:20:17 UTC
 plan-git-harden-sh-design-spec-8b87@crosslink ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIC3h70Zc6CSo7PkaMRBZuV9N/Z/p5UIL9x22Sl2Qvhwj crosslink-agent:plan-git-harden-sh-design-spec-8b87@MacBook-Air-4.local
+# approved by flo at 2026-03-27 16:44:46 UTC
+plan-git-harden-sh-design-spec-2153@crosslink ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIBwDU4LSGVWu7leZ/Y5RSz/UnZHkgdInXPr21KI1Bjku crosslink-agent:plan-git-harden-sh-design-spec-2153@MacBook-Air-4.local
diff --git a/trust/approvals/plan-git-harden-sh-design-spec-2153.json b/trust/approvals/plan-git-harden-sh-design-spec-2153.json
new file mode 100644
index 0000000..efde30d
--- /dev/null
+++ b/trust/approvals/plan-git-harden-sh-design-spec-2153.json
@@ -0,0 +1,6 @@
+{
+  "agent_id": "plan-git-harden-sh-design-spec-2153",
+  "principal": "plan-git-harden-sh-design-spec-2153@crosslink",
+  "approved_by": null,
+  "approved_at": "2026-03-27T16:44:46.355089+00:00"
+}
\ No newline at end of file