diff --git a/auth.php b/auth.php
index 91c2321..38ab397 100644
--- a/auth.php
+++ b/auth.php
@@ -32,6 +32,11 @@
  */
 class auth_plugin_basic extends auth_plugin_base {
 
+    /**
+     * Defaults.
+     *
+     * @var int[]
+     */
     public $defaults = array(
         'debug'     => 0,
         'send401'   => 0,
@@ -49,9 +54,9 @@ public function __construct() {
     /**
      * A debug function, dumps to the php log as well as into the
      * response headers for easy curl based debugging
-     *
+     * @param string $msg Message
      */
-    private function log($msg) {
+    private function log(string $msg) {
         if ($this->config->debug) {
             // @codingStandardsIgnoreStart
             error_log('auth_basic: ' . $msg);
@@ -161,17 +166,16 @@ public function loginpage_hook() {
      * @param string $username The username
      * @param string $password The password
      * @return bool Authentication success or failure.
-     *
-     * @SuppressWarnings("unused")
      */
     public function user_login ($username, $password) {
         return false;
     }
 
     /**
+     * Check if provided password is master password.
+     *
      * @param $userpassword
      * @return bool
-     * @throws dml_exception
      */
     private function is_master_password($userpassword) {
         global $CFG, $DB;
@@ -213,8 +217,9 @@ private function get_random_user() {
 
     /**
      * Get a user by site role.
+     *
+     * @param mixed $roleid Role ID
      * @return bool|mixed
-     * @throws dml_exception
      */
     private function get_random_user_by_roleid($roleid) {
         $sql = "SELECT u.*
@@ -243,7 +248,10 @@ private function get_random_user_by_courseid($courseid) {
      * Get a user who is enrolled in a course with a specified role.
      * This will only get student with role at Course Level.
      * It will ignore roles at other context level (module, category, block, site).
-     * @param $courseid
+     *
+     * @param mixed $courseid
+     * @param mixed $roleid Role ID
+     *
      * @return bool|mixed
      * @throws dml_exception
      */
@@ -260,9 +268,9 @@ private function get_random_user_by_courseid_with_roleid($courseid, $roleid) {
 
     /**
      * Get user based on template value.
-     * @param $template
+     *
+     * @param mixed $template
      * @return bool|mixed
-     * @throws dml_exception
      */
     private function get_user($template) {
         $user = false;
@@ -300,12 +308,13 @@ private function get_user($template) {
 
     /**
      * Get random record.
-     * @param $sql
-     * @param null $params
+     *
+     * @param string $sql SQL
+     * @param null|array $params
      * @return mixed
      * @throws dml_exception
      */
-    private function random_record($sql, $params=null) {
+    private function random_record(string $sql, ?array $params = null) {
         global $DB;
         if ($DB->get_dbfamily() == 'mysql') {
             $sql = $sql . " ORDER BY rand() LIMIT 1";
diff --git a/classes/form/savepassword.php b/classes/form/savepassword.php
index bf87d19..7bb4dff 100644
--- a/classes/form/savepassword.php
+++ b/classes/form/savepassword.php
@@ -14,6 +14,10 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
 
+
+defined('MOODLE_INTERNAL') || die();
+require_once("$CFG->libdir/formslib.php");
+
 /**
  * Master Password Form
  *
@@ -21,12 +25,13 @@
  * @copyright  2018 Nathan Nguyen <nathannguyen@catalyst-au.nete>
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-
-defined('MOODLE_INTERNAL') || die();
-require_once("$CFG->libdir/formslib.php");
-
 class savepassword extends moodleform {
 
+    /**
+     * Form definition.
+     *
+     * @return void
+     */
     protected function definition() {
         $mform = $this->_form;
 
diff --git a/classes/privacy/provider.php b/classes/privacy/provider.php
index 57adca0..abb0616 100644
--- a/classes/privacy/provider.php
+++ b/classes/privacy/provider.php
@@ -13,13 +13,6 @@
 //
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
-/**
- * Privacy Subsystem implementation for auth_basic.
- *
- * @package    auth_basic
- * @copyright  2018 Olivier SECRET <olivier.secret@catalyst-au.net>
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
 
 namespace auth_basic\privacy;
 
@@ -33,6 +26,13 @@
 use core_privacy\local\request\userlist;
 use core_privacy\local\request\writer;
 
+/**
+ * Privacy Subsystem implementation for auth_basic.
+ *
+ * @package    auth_basic
+ * @copyright  2018 Olivier SECRET <olivier.secret@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
 class provider implements
     \core_privacy\local\metadata\provider,
     \core_privacy\local\request\core_userlist_provider,
diff --git a/db/upgrade.php b/db/upgrade.php
index 22ab962..91725b3 100644
--- a/db/upgrade.php
+++ b/db/upgrade.php
@@ -24,6 +24,11 @@
 
 defined('MOODLE_INTERNAL') || die();
 
+/**
+ * Upgrade hook.
+ *
+ * @param int $oldversion the version we are upgrading from
+ */
 function xmldb_auth_basic_upgrade($oldversion) {
     global $DB;
 
diff --git a/tests/auth_basic_test.php b/tests/auth_basic_test.php
index bfebcee..67dba58 100644
--- a/tests/auth_basic_test.php
+++ b/tests/auth_basic_test.php
@@ -13,19 +13,19 @@
 //
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
-/**
- * Base class for unit tests for auth_basic.
- *
- * @package    auth_basic
- * @category   test
- * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
 
 defined('MOODLE_INTERNAL') || die();
 
 global $CFG;
 require_once($CFG->dirroot.'/auth/basic/auth.php');
 
+/**
+ * Base class for unit tests for auth_basic.
+ * @package    auth_basic
+ * @category   test
+ * @copyright  Brendan Heywood <brendan@catalyst-au.net>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
 class auth_basic_test extends advanced_testcase {
     /** @var auth_plugin_basic Keeps the authentication plugin. */
     protected $authplugin;