diff --git a/update-makefiles.sh b/update-makefiles.sh
index b7e4235..14c5b01 100755
--- a/update-makefiles.sh
+++ b/update-makefiles.sh
@@ -1,4 +1,12 @@
 #!/bin/bash
+# Script to update Android make-files for HAL and VTS modules.
+
+set -e
+
+if [ -z "$ANDROID_BUILD_TOP" ]; then
+    echo "Missing ANDROID_BUILD_TOP env variable. Run 'lunch' first."
+    exit 1
+fi
 
 source $ANDROID_BUILD_TOP/system/tools/hidl/update-makefiles-helper.sh
 
@@ -6,3 +14,8 @@
   "android.hardware:hardware/interfaces" \
   "android.hidl:system/libhidl/transport"
 
+echo "Updating files at $ANDROID_BUILD_TOP/test/vts-testcase/hal"
+pushd $ANDROID_BUILD_TOP/test/vts-testcase/hal
+./script/update_makefiles.py
+popd
+