diff --git a/tests/include/drivers/keygen.h b/tests/include/drivers/keygen.h
index f0eb569..af1f499 100644
--- a/tests/include/drivers/keygen.h
+++ b/tests/include/drivers/keygen.h
@@ -1,5 +1,5 @@
 /*
- * Test driver for signature functions
+ * Test driver for generating keys.
  */
 /*  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0
diff --git a/tests/include/drivers/signature.h b/tests/include/drivers/signature.h
index 900f0c8..1506bac 100644
--- a/tests/include/drivers/signature.h
+++ b/tests/include/drivers/signature.h
@@ -1,5 +1,5 @@
 /*
- * Test driver for signature functions
+ * Test driver for signature functions.
  */
 /*  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0