diff --git a/tests/test-wipe-lib.sh b/tests/test_is_usb_device.sh
similarity index 94%
rename from tests/test-wipe-lib.sh
rename to tests/test_is_usb_device.sh
index dd0e6ad..bfc99db 100755
--- a/tests/test-wipe-lib.sh
+++ b/tests/test_is_usb_device.sh
@@ -1,5 +1,6 @@
 #!/bin/bash
-# Test the is_usb_device logic from wipe-lib.sh
+# Tests for is_usb_device() in autorun/wipe-lib.sh (distinct from
+# test_wipe-lib.sh, which covers detect_drive_type()).
 set -euo pipefail
 
 # Find repo root