diff --git a/bin/gstack-repo-mode b/bin/gstack-repo-mode
index 0c9ce904..563f6a16 100755
--- a/bin/gstack-repo-mode
+++ b/bin/gstack-repo-mode
@@ -13,7 +13,12 @@ set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
 # Compute SLUG directly (avoid eval of gstack-slug — branch names can contain shell metacharacters)
-SLUG=$(git remote get-url origin 2>/dev/null | sed 's|.*[:/]\([^/]*/[^/]*\)\.git$|\1|;s|.*[:/]\([^/]*/[^/]*\)$|\1|' | tr '/' '-')
+REMOTE_URL=$(git remote get-url origin 2>/dev/null || true)
+if [ -z "$REMOTE_URL" ]; then
+  echo "REPO_MODE=unknown"
+  exit 0
+fi
+SLUG=$(echo "$REMOTE_URL" | sed 's|.*[:/]\([^/]*/[^/]*\)\.git$|\1|;s|.*[:/]\([^/]*/[^/]*\)$|\1|' | tr '/' '-')
 [ -z "${SLUG:-}" ] && { echo "REPO_MODE=unknown"; exit 0; }
 
 # Validate: only allow known values (prevent shell injection via source <(...))