diff --git a/classes/aggregator.php b/classes/aggregator.php
index 4afc621..a079aec 100644
--- a/classes/aggregator.php
+++ b/classes/aggregator.php
@@ -194,7 +194,7 @@ abstract class aggregator {
     /**
      * Webservice structure for basic aggregator info
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     public static function basic_structure($value = VALUE_REQUIRED) {
         return new \external_single_structure([
diff --git a/classes/badgeinfo.php b/classes/badgeinfo.php
index a5e50db..f5b35f2 100644
--- a/classes/badgeinfo.php
+++ b/classes/badgeinfo.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Handle badge information 
  * @package    local_treestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
@@ -24,10 +24,22 @@ namespace local_treestudyplan;
 defined('MOODLE_INTERNAL') || die();
 
 require_once($CFG->libdir.'/externallib.php');
+use \core_badges\badge;
 
+/**
+ * Handle badge information in the same style as the other classes
+ */
 class badgeinfo {
-    private $badge; // Holds database record.
+    /**
+     * Holds database record
+     * @var \core_badges\badge
+     */
+    private $badge;
 
+    /**
+     * Maps badge status to strings
+     * @var array
+     */
     private const STATUSINFO = [
         BADGE_STATUS_INACTIVE => 'inactive',
         BADGE_STATUS_ACTIVE => 'active',
@@ -35,6 +47,11 @@ class badgeinfo {
         BADGE_STATUS_ACTIVE_LOCKED => 'active',
         BADGE_STATUS_ARCHIVED => 'archived',
     ];
+
+    /**
+     * Maps badge status to locked or not
+     * @var array
+     */
     private const LOCKEDINFO = [
         BADGE_STATUS_INACTIVE => 0,
         BADGE_STATUS_ACTIVE => 0,
@@ -43,8 +60,11 @@ class badgeinfo {
         BADGE_STATUS_ARCHIVED => 1, // We don't want to edit archived badges anyway....     .
     ];
 
-    public function __construct(\core_badges\badge $badge) {
-        global $DB;
+    /**
+     * Construct new badgeinfo object
+     * @param badge $badge Badge object to use
+     */
+    public function __construct(badge $badge) {
         $this->badge = $badge;
     }
 
@@ -56,12 +76,22 @@ class badgeinfo {
         return $this->badge->name;
     }
 
+    /**
+     * Get the badge id from the badge name
+     * @param string $name Badge name
+     * @return int Badge id
+     */
     public static function id_from_name($name) {
         global $DB;
 
         return $DB->get_field("badge", "id", ['name' => $name]);
     }
 
+    /**
+     * Check if a given badge exists
+     * @param int $id Badge id
+     * @return bool
+     */
     public static function exists($id) {
         global $DB;
         return is_numeric($id) && $DB->record_exists('badge', array('id' => $id));
@@ -92,6 +122,7 @@ class badgeinfo {
 
     /**
      * Webservice model for editor info
+     * @param int[] $studentlist List of user id's to use for checking issueing progress within a study plan
      * @return array Webservice data model
      */
     public function editor_model(array $studentlist = null) {
@@ -197,6 +228,11 @@ class badgeinfo {
         return $badge;
     }
 
+    /**
+     * Count how many of the students in the array have this badge issued
+     * @param int[] $studentids List of user id's to check
+     * @return int
+     */
     public function count_issued(array $studentids) {
         $issuecount = 0;
 
diff --git a/classes/contextinfo.php b/classes/contextinfo.php
index 5ffb405..9f42535 100644
--- a/classes/contextinfo.php
+++ b/classes/contextinfo.php
@@ -41,7 +41,7 @@ class contextinfo {
     /**
      * Describe the result for the webservice model
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     public static function structure($value = VALUE_REQUIRED) {
         return new \external_single_structure([
diff --git a/classes/courseinfo.php b/classes/courseinfo.php
index 42c37a3..fea7c67 100644
--- a/classes/courseinfo.php
+++ b/classes/courseinfo.php
@@ -236,7 +236,7 @@ class courseinfo {
     /**
      * Webservice structure for basic info
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     public static function simple_structure($value = VALUE_REQUIRED) {
         return new \external_single_structure([
diff --git a/classes/gradeinfo.php b/classes/gradeinfo.php
index bfabf58..a9d1f1b 100644
--- a/classes/gradeinfo.php
+++ b/classes/gradeinfo.php
@@ -145,7 +145,7 @@ class gradeinfo {
     /**
      * Get a specific course context from grade item id
      * @param int $id Grade item id
-     * @return context_course
+     * @return \context_course
      * @throws InvalidArgumentException if grade id is not found
      */
     public static function get_coursecontext_by_id($id) : \context_course {
@@ -251,7 +251,7 @@ class gradeinfo {
     /**
      * Webservice structure for editor info
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     /**
      * Webservice structure for editor info
@@ -305,7 +305,7 @@ class gradeinfo {
     /**
      * Webservice structure for user info
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     /**
      * Webservice structure for userinfo
diff --git a/classes/period.php b/classes/period.php
index 735a976..e32fdd3 100644
--- a/classes/period.php
+++ b/classes/period.php
@@ -35,7 +35,7 @@ class period {
      * Holds database record
      * @var stdClass
      */
-    private $r; // Holds database record.
+    private $r;
     /** @var int */
     private $id;
     /** @var studyplanpage */
@@ -46,6 +46,11 @@ class period {
     }
 
     // Cache constructors to avoid multiple creation events in one session.
+    /**
+     * Find record in database and return management object
+     * @param int $id Id of database record
+     * @return self 
+     */
     public static function find_by_id($id): self {
         if (!array_key_exists($id, self::$cache)) {
             self::$cache[$id] = new self($id);
@@ -123,6 +128,10 @@ class period {
         return self::$pagecache[$page->id()];
     }
 
+    /**
+     * Construct new instance from DB record
+     * @param int $id Id of database record
+     */
     private function __construct($id) {
         global $DB;
         $this->id = $id;
@@ -166,10 +175,18 @@ class period {
         return $this->r->period;
     }
 
+    /**
+     * Start date
+     * @return \DateTime
+     */
     public function startdate() {
         return new \DateTime($this->r->startdate);
     }
 
+    /**
+     * End date
+     * @return \DateTime
+     */
     public function enddate() {
         if ($this->r->enddate && strlen($this->r->enddate) > 0) {
             return new \DateTime($this->r->enddate);
diff --git a/classes/studentstudyplanservice.php b/classes/studentstudyplanservice.php
index b4f1524..34aa37d 100644
--- a/classes/studentstudyplanservice.php
+++ b/classes/studentstudyplanservice.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Webservice class for retrieving student studyplans
  * @package    local_treestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
@@ -28,8 +28,14 @@ require_once($CFG->libdir.'/externallib.php');
 use \local_treestudyplan\local\helpers\webservicehelper;
 
 require_once($CFG->libdir.'/badgeslib.php');
-
+/**
+ * Webservice class for retrieving student studyplans
+ */
 class studentstudyplanservice extends \external_api {
+    /**
+     * Capability required to view studyplans of other users
+     * @var string
+     */
     const CAP_VIEWOTHER = "local/treestudyplan:viewuserreports";
     /************************
      *                      *
@@ -57,7 +63,12 @@ class studentstudyplanservice extends \external_api {
         );
     }
 
-    private static function list_user_studyplans($userid) {
+    /**
+     * Return overview of the studyplans for a specific user
+     * @param int $userid ID of user to check specific info for
+     * @return array
+     */
+    public static function list_user_studyplans($userid) {
         global $CFG, $DB;
 
         $list = [];
@@ -96,6 +107,12 @@ class studentstudyplanservice extends \external_api {
             studyplan::user_structure()
         );
     }
+
+    /**
+     * Get the full studyplans for a specific user
+     * @param int $userid ID of user to check specific info for
+     * @return array
+     */
     public static function get_user_studyplans($userid) {
         global $CFG, $DB;
 
@@ -136,6 +153,13 @@ class studentstudyplanservice extends \external_api {
     public static function get_user_studyplan_returns() {
         return studyplan::user_structure();
     }
+
+    /**
+     * Get a specific studyplan for a given user
+     * @param int $userid ID of user to check specific info for
+     * @param int $studyplanid ID of studyplan to view
+     * @return array
+     */
     public static function get_user_studyplan($userid, $studyplanid) {
         global $CFG, $DB;
 
@@ -174,6 +198,12 @@ class studentstudyplanservice extends \external_api {
             studyplan::user_structure()
         );
     }
+
+    /**
+     * Get studyplan based on invite key
+     * @param int $invitekey Invitation key
+     * @return array
+     */
     public static function get_invited_studyplan($invitekey) {
         global $CFG, $DB;
 
@@ -224,7 +254,11 @@ class studentstudyplanservice extends \external_api {
         );
     }
 
-    private static function list_own_studyplans() {
+    /**
+     * Return overview of the studyplans the current user is linked to
+     * @return array
+     */
+    public static function list_own_studyplans() {
         global $CFG, $DB, $USER;
         $userid = $USER->id;
 
@@ -262,6 +296,11 @@ class studentstudyplanservice extends \external_api {
         );
     }
 
+    /**
+     * Get all studyplans for current user or a specific one
+     * @param int $id Optional id of specific studyplan
+     * @return array
+     */
     public static function get_own_studyplan($id = null) {
         global $USER;
 
@@ -314,6 +353,11 @@ class studentstudyplanservice extends \external_api {
         );
     }
 
+    /**
+     * Get all or one studyplan the current user is teaching in
+     * @param int $id Optional specific id of studyplan
+     * @return array
+     */
     public static function get_teaching_studyplans($id = null) {
         global $CFG, $DB, $USER;
         $userid = $USER->id;
diff --git a/classes/studyitem.php b/classes/studyitem.php
index e6e58b6..136958f 100644
--- a/classes/studyitem.php
+++ b/classes/studyitem.php
@@ -42,14 +42,14 @@ class studyitem {
      * Holds database record
      * @var stdClass
      */
-    private $r; // Holds database record.
+    private $r;
     /** @var int */
     private $id;
 
     private $courseinfo = null;
     private $studyline;
-    /** @var aggragator[] */
-    /** @var aggragator */
+    /** @var aggregator[] */
+    /** @var aggregator */
     private $aggregator;
 
 
@@ -69,6 +69,11 @@ class studyitem {
         return $this->r->conditions;
     }
 
+    /**
+     * Find record in database and return management object
+     * @param int $id Id of database record
+     * @return self 
+     */
     public static function find_by_id($id): self {
         if (!array_key_exists($id, self::$studyitemcache)) {
             self::$studyitemcache[$id] = new self($id);
@@ -315,12 +320,16 @@ class studyitem {
         global $DB;
 
         foreach ($resequence as $sq) {
-            $DB->update_record(self::TABLE, [
-                'id' => $sq['id'],
-                'line_id' => $sq['line_id'],
-                'slot' => $sq['slot'],
-                'layer' => $sq['layer'],
-            ]);
+            // Only change line_id if new line is within the same studyplan page
+            if ( studyitem::find_by_id($sq['id'])->studyline()->page()->id() == 
+                 studyline::find_by_id($sq['line_id'])->page()->id() ) {
+                $DB->update_record(self::TABLE, [
+                    'id' => $sq['id'],
+                    'line_id' => $sq['line_id'],
+                    'slot' => $sq['slot'],
+                    'layer' => $sq['layer'],
+                ]);
+            }
         }
 
         return success::success();
diff --git a/classes/studyitemconnection.php b/classes/studyitemconnection.php
index 86bb89a..3ce01fe 100644
--- a/classes/studyitemconnection.php
+++ b/classes/studyitemconnection.php
@@ -55,7 +55,7 @@ class studyitemconnection {
     /**
      * Webservice structure for basic info
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     public static function structure($value = VALUE_REQUIRED) {
         return new \external_single_structure([
diff --git a/classes/studyline.php b/classes/studyline.php
index d650750..de1de40 100644
--- a/classes/studyline.php
+++ b/classes/studyline.php
@@ -51,7 +51,7 @@ class studyline {
      * Holds database record
      * @var stdClass
      */
-    private $r; // Holds database record.
+    private $r;
     /** @var int */
     private $id;
     /** @var studyplanpage */
@@ -76,6 +76,11 @@ class studyline {
         return $this->page;
     }
 
+    /**
+     * Find record in database and return management object
+     * @param int $id Id of database record
+     * @return self 
+     */
     public static function find_by_id($id): self {
         if (!array_key_exists($id, self::$studylinecache)) {
             self::$studylinecache[$id] = new self($id);
@@ -83,6 +88,10 @@ class studyline {
         return self::$studylinecache[$id];
     }
 
+    /**
+     * Construct new instance from DB record
+     * @param int $id Id of database record
+     */
     private function __construct($id) {
         global $DB;
         $this->id = $id;
diff --git a/classes/studyplan.php b/classes/studyplan.php
index 4bca67b..3ec054f 100644
--- a/classes/studyplan.php
+++ b/classes/studyplan.php
@@ -35,10 +35,10 @@ class studyplan {
      * Holds database record
      * @var stdClass
      */
-    private $r; // Holds database record.
+    private $r;
     /** @var int */
     private $id;
-    /** @var aggragator */
+    /** @var aggregator */
     private $aggregator;
     private $context = null; // Hold context object once retrieved.
     private $linkeduserids = null; // Cache lookup of linked users (saves queries).
@@ -50,6 +50,11 @@ class studyplan {
     }
 
     // Cache constructors to avoid multiple creation events in one session.
+    /**
+     * Find record in database and return management object
+     * @param int $id Id of database record
+     * @return self 
+     */
     public static function find_by_id($id): self {
         if (!array_key_exists($id, self::$studyplancache)) {
             self::$studyplancache[$id] = new self($id);
@@ -57,6 +62,10 @@ class studyplan {
         return self::$studyplancache[$id];
     }
 
+    /**
+     * Construct new instance from DB record
+     * @param int $id Id of database record
+     */
     private function __construct($id) {
         global $DB;
         $this->id = $id;
@@ -119,7 +128,7 @@ class studyplan {
     /**
      * Webservice structure for basic info
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     public static function simple_structure($value = VALUE_REQUIRED) {
         return new \external_single_structure([
@@ -546,6 +555,10 @@ class studyplan {
         return $newplan;
     }
 
+    /**
+     * Description of export structure for webservices
+     * @return \external_description
+     */
     public static function export_structure() {
         return new \external_single_structure([
             "format" => new \external_value(PARAM_TEXT, 'format of studyplan export'),
diff --git a/classes/studyplanpage.php b/classes/studyplanpage.php
index 2eb5434..3be1d30 100644
--- a/classes/studyplanpage.php
+++ b/classes/studyplanpage.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Studyplan page management class
  * @package    local_treestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
@@ -24,11 +24,18 @@ namespace local_treestudyplan;
 defined('MOODLE_INTERNAL') || die();
 
 require_once($CFG->libdir.'/externallib.php');
-
+/**
+ * Studyplan page management class
+ */
 class studyplanpage {
 
-    /** @var string */
+    /** 
+     * Database table this class models for
+     * @var string */
     const TABLE = "local_treestudyplan_page";
+    /**
+     * Cache for finding previously loaded pages
+     * @var array */
     private static $cache = [];
 
     /**
@@ -41,11 +48,19 @@ class studyplanpage {
     /** @var studyplan*/
     private $studyplan;
 
-    public function aggregator() {
+    /**
+     * Get aggregator for the studyplan (page)
+     * @return aggregator
+     */
+    public function aggregator() : aggregator {
         return $this->studyplan->aggregator();
     }
 
-    // Cache constructors to avoid multiple creation events in one session.
+    /**
+     * Find record in database and return management object
+     * @param int $id Id of database record
+     * @return self 
+     */
     public static function find_by_id($id): self {
         if (!array_key_exists($id, self::$cache)) {
             self::$cache[$id] = new self($id);
@@ -53,6 +68,10 @@ class studyplanpage {
         return self::$cache[$id];
     }
 
+    /**
+     * Construct new instance from DB record
+     * @param int $id Id of database record
+     */
     private function __construct($id) {
         global $DB;
         $this->id = $id;
@@ -68,6 +87,9 @@ class studyplanpage {
         return $this->id;
     }
 
+    /**
+     * Find studyplan for this page
+     */
     public function studyplan() : studyplan {
         return $this->studyplan;
     }
@@ -80,6 +102,9 @@ class studyplanpage {
         return $this->r->shortname;
     }
 
+    /**
+     * Numer of periods for this page
+     */
     public function periods() {
         return $this->r->periods;
     }
@@ -92,10 +117,18 @@ class studyplanpage {
         return $this->r->fullname;
     }
 
+    /**
+     * Start date
+     * @return \DateTime
+     */
     public function startdate() {
         return new \DateTime($this->r->startdate);
     }
 
+    /**
+     * End date
+     * @return \DateTime
+     */
     public function enddate() {
         if ($this->r->enddate && strlen($this->r->enddate) > 0) {
             return new \DateTime($this->r->enddate);
@@ -109,7 +142,7 @@ class studyplanpage {
     /**
      * Webservice structure for basic info
      * @param int $value Webservice requirement constant
-     * @return external_single_structure Webservice output structure
+     * @return \external_description Webservice output structure
      */
     public static function simple_structure($value = VALUE_REQUIRED) {
         return new \external_single_structure([
@@ -186,6 +219,11 @@ class studyplanpage {
         return $model;
     }
 
+    /**
+     * Add new study plan page
+     * @param mixed $fields Parameter for new study plan page
+     * @return self
+     */
     public static function add($fields) {
         global $CFG, $DB;
 
@@ -210,6 +248,11 @@ class studyplanpage {
         return self::find_by_id($id); // Make sure the new page is immediately cached.
     }
 
+    /**
+     * Edit studyplan page
+     * @param mixed $fields Parameters to change
+     * @return self
+     */
     public function edit($fields) {
         global $DB;
         $editable = ['fullname', 'shortname', 'description', 'periods', 'startdate', 'enddate'];
@@ -230,6 +273,11 @@ class studyplanpage {
         return $this;
     }
 
+    /**
+     * Delete study plan page
+     * @param bool $force Force deletion even if not empty
+     * @return success
+     */
     public function delete($force = false) {
         global $DB;
 
@@ -293,6 +341,11 @@ class studyplanpage {
         return $model;
     }
 
+    /**
+     * Find list of pages belonging to a specified study plan
+     * @param studyplan $plan Studyplan to search pages for
+     * @return self[]
+     */
     public static function find_studyplan_children(studyplan $plan) {
         global $DB;
         $list = [];
@@ -304,13 +357,24 @@ class studyplanpage {
         return $list;
     }
 
-    public static function duplicate_page($pageid, $name, $shortname) {
+    /**
+     * Duplicate a studyplan page
+     * @param int $pageid Id of the page to copy
+     * @param studyplan $newstudyplan Studyplan to copy the page into
+     * @return self
+     */
+    public static function duplicate_page(int $pageid, studyplan $newstudyplan) {
         $ori = self::find_by_id($pageid);
-        $new = $ori->duplicate($name, $shortname);
-        return $new->simple_model();
+        $new = $ori->duplicate($newstudyplan);
+        return $new;
     }
 
-    public function duplicate($newstudyplan) {
+    /**
+     * Duplicate this studyplan page
+     * @param studyplan $newstudyplan Studyplan to copy the page into
+     * @return self
+     */
+    public function duplicate(studyplan $newstudyplan) {
         // First duplicate the studyplan structure.
         $new = self::add([
             'studyplan_id' => $newstudyplan->id(),
@@ -345,6 +409,10 @@ class studyplanpage {
         return $new;
     }
 
+    /**
+     * Description of export structure for webservices
+     * @return \external_description
+     */
     public static function export_structure() {
         return new \external_single_structure([
             "format" => new \external_value(PARAM_TEXT, 'format of studyplan export'),
@@ -352,6 +420,10 @@ class studyplanpage {
         ], 'Exported studyplan');
     }
 
+    /**
+     * Export this page into a json model
+     * @return array
+     */
     public function export_page() {
         $model = $this->export_model();
         $json = json_encode([
@@ -362,6 +434,10 @@ class studyplanpage {
         return [ "format" => "application/json", "content" => $json];
     }
 
+    /**
+     * Export this page into a csv model
+     * @return array
+     */
     public function export_page_csv() {
         $plist = period::find_for_page($this);
 
@@ -436,6 +512,10 @@ class studyplanpage {
         return [ "format" => "text/csv", "content" => $csv];
     }
 
+    /**
+     * Export this page's studylines into a json model
+     * @return array
+     */
     public function export_studylines() {
         $model = $this->export_studylines_model();
         $json = json_encode([
@@ -446,6 +526,10 @@ class studyplanpage {
         return [ "format" => "application/json", "content" => $json];
     }
 
+    /**
+     * Export this pages periods into a json model
+     * @return array
+     */
     public function export_periods() {
         $model = period::page_model($this);
         $json = json_encode([
@@ -474,6 +558,10 @@ class studyplanpage {
         return $model;
     }
 
+    /**
+     * Export this pages periods into an array before serialization
+     * @return array
+     */
     public function export_studylines_model() {
         $children = studyline::find_page_children($this);
         $lines = [];
@@ -483,6 +571,11 @@ class studyplanpage {
         return $lines;
     }
 
+    /**
+     * Import periods from file contents
+     * @param string $content String
+     * @param string $format Format description
+     */
     public function import_periods($content, $format = "application/json") {
         if ($format != "application/json") {
             return false;
@@ -497,6 +590,11 @@ class studyplanpage {
         }
     }
 
+    /**
+     * Import studylines from file contents
+     * @param string $content String
+     * @param string $format Format description
+     */
     public function import_studylines($content, $format = "application/json") {
         if ($format != "application/json") {
             return false;
@@ -513,6 +611,11 @@ class studyplanpage {
         }
     }
 
+    /**
+     * Find a studyline in this page by its shortname
+     * @param string $shortname 
+     * @return studyline|null
+     */
     protected function find_studyline_by_shortname($shortname) {
         $children = studyline::find_page_children($this);
         foreach ($children as $l) {
@@ -523,6 +626,10 @@ class studyplanpage {
         return null;
     }
 
+    /**
+     * Import periods from decoded array model
+     * @param array $model Decoded array
+     */
     public function import_periods_model($model) {
         $periods = period::find_for_page($this);
         foreach ($model as $pmodel) {
@@ -533,6 +640,10 @@ class studyplanpage {
         }
     }
 
+    /**
+     * Import studylines from decoded array model
+     * @param array $model Decoded array
+     */
     public function import_studylines_model($model) {
         // First attempt to map each studyline model to an existing or new line.
         $linemap = [];
diff --git a/classes/studyplanservice.php b/classes/studyplanservice.php
index c2c1f9c..193cd61 100644
--- a/classes/studyplanservice.php
+++ b/classes/studyplanservice.php
@@ -14,7 +14,7 @@
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <https://www.gnu.org/licenses/>.
 /**
- *
+ * Webservice class for managing studyplans
  * @package    local_treestudyplan
  * @copyright  2023 P.M. Kuipers
  * @license    https://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
@@ -30,9 +30,19 @@ require_once($CFG->libdir.'/badgeslib.php');
 require_once($CFG->libdir.'/gradelib.php');
 require_once($CFG->dirroot.'/course/modlib.php');
 
+/**
+ * Webservice class for managing studyplans
+ */
 class studyplanservice extends \external_api {
-
+    /**
+     * Capability required to edit study plans
+     * @var string
+     */
     const CAP_EDIT = "local/treestudyplan:editstudyplan";
+    /**
+     * Capability required to view studyplans (for other users)
+     * @var string
+     */
     const CAP_VIEW = "local/treestudyplan:viewuserreports";
 
     /************************
@@ -59,6 +69,11 @@ class studyplanservice extends \external_api {
         return new \external_multiple_structure( studyplan::simple_structure() );
     }
 
+    /**
+     * Get overview of all studyplans in a given context
+     * @param int $contextid Id of context to view (defaults to systemcontext)
+     * @return array
+     */
     public static function list_studyplans($contextid = 0) {
         global $CFG, $DB;
 
@@ -100,6 +115,11 @@ class studyplanservice extends \external_api {
         return  studyplan::editor_structure();
     }
 
+    /**
+     * Get editor model for specific studyplan
+     * @param int $id Id of studyplan
+     * @return array
+     */
     public static function get_studyplan_map($id) {
         if (isset($id) && $id > 0) {
             $studyplan = studyplan::find_by_id($id);
@@ -134,6 +154,11 @@ class studyplanservice extends \external_api {
         return new \external_multiple_structure( studyline::editor_structure() );
     }
 
+    /**
+     * Get editor model for specific study line
+     * @param int $id ID of study line
+     * @return array
+     */
     public static function get_studyline_map($id) {
 
         $o = studyline::find_by_id($id);
@@ -174,6 +199,20 @@ class studyplanservice extends \external_api {
         return studyplan::simple_structure();
     }
 
+    /**
+     * Add a new studyplan in a given context
+     * @param mixed $name
+     * @param mixed $shortname
+     * @param mixed $idnumber
+     * @param mixed $description
+     * @param mixed $periods
+     * @param mixed $startdate
+     * @param mixed $enddate
+     * @param string $aggregation
+     * @param string $aggregationconfig
+     * @param int $contextid
+     * @return array
+     */
     public static function add_studyplan($name, $shortname, $idnumber, $description, $periods,
                                          $startdate, $enddate, $aggregation = "bistate", $aggregationconfig = '', $contextid = 0) {
         // Check if we have the proper rights for the requested context.
@@ -229,6 +268,21 @@ class studyplanservice extends \external_api {
         return studyplan::simple_structure();
     }
 
+    /**
+     * Edit studyplan parameters
+     * @param mixed $id
+     * @param mixed $name
+     * @param mixed $shortname
+     * @param mixed $idnumber
+     * @param mixed $description
+     * @param mixed $periods
+     * @param mixed $startdate
+     * @param mixed $enddate
+     * @param string $aggregation
+     * @param string $aggregationconfig
+     * @param int $contextid
+     * @return array
+     */
     public static function edit_studyplan($id, $name, $shortname, $idnumber, $description, $periods, $startdate,
                                           $enddate, $aggregation = "bistate", $aggregationconfig = '', $contextid = 0) {
         // Validate access in the intended context.
@@ -279,6 +333,12 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Delete a studyplan
+     * @param mixed $id Id of the studyplan
+     * @param bool $force Force deletion, even though studyplan is not empty
+     * @return array Succes/fail model
+     */
     public static function delete_studyplan($id, $force = false) {
         $o = studyplan::find_by_id($id);
         // Validate if the requesting user has the right to edit the plan in it's current context.
@@ -314,6 +374,15 @@ class studyplanservice extends \external_api {
         return studyline::editor_structure();
     }
 
+    /**
+     * Add a new study line
+     * @param mixed $pageid
+     * @param mixed $name
+     * @param mixed $shortname
+     * @param mixed $color
+     * @param mixed $sequence
+     * @return array
+     */
     public static function add_studyline($pageid, $name, $shortname, $color, $sequence) {
         // Validate if the requesting user has the right to edit the plan in it's current context.
         $page = studyplanpage::find_by_id($pageid);
@@ -356,6 +425,14 @@ class studyplanservice extends \external_api {
         return studyline::editor_structure();
     }
 
+    /**
+     * Edit studyline parameters
+     * @param mixed $id
+     * @param mixed $name
+     * @param mixed $shortname
+     * @param mixed $color
+     * @return [type]
+     */
     public static function edit_studyline($id, $name, $shortname, $color) {
         $o = studyline::find_by_id($id);
         // Validate if the requesting user has the right to edit the plan in it's current context.
@@ -393,12 +470,17 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Delete a study line
+     * @param mixed $id Id of the studyline
+     * @return array Success/fail model
+     * 
+     */
     public static function delete_studyline($id) {
         $o = studyline::find_by_id($id);
         // Validate if the requesting user has the right to edit the plan in it's current context.
         webservicehelper::require_capabilities(self::CAP_EDIT, $o->context());
         return $o->delete()->model();
-
     }
 
     /************************
@@ -430,6 +512,11 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Reorder study lines
+     * @param int[] $resequence New order of study lines by id
+     * @return [type]
+     */
     public static function reorder_studylines($resequence) {
         // Validate if the requesting user has the right to edit the lines in it's current context.
         foreach ($resequence as $sq) {
@@ -468,6 +555,11 @@ class studyplanservice extends \external_api {
         return studyitem::editor_structure();
     }
 
+    /**
+     * Get editor model for study item
+     * @param mixed $id ID of study item
+     * @return array
+     */
     public static function get_studyitem($id) {
         $o = studyitem::find_by_id($id);
         webservicehelper::require_capabilities([self::CAP_EDIT, self::CAP_VIEW], $o->context());
@@ -509,6 +601,15 @@ class studyplanservice extends \external_api {
         return studyitem::editor_structure();
     }
 
+    /**
+     * Add a new study item
+     * @param int $lineid
+     * @param string $type 
+     * @param array $details
+     * @param int $slot
+     * @param int $layer
+     * @return array
+     */
     public static function add_studyitem($lineid, $type, $details, $slot = -1, $layer = 0) {
         webservicehelper::require_capabilities(self::CAP_EDIT, studyline::find_by_id($lineid)->context());
 
@@ -551,6 +652,13 @@ class studyplanservice extends \external_api {
         return studyitem::editor_structure();
     }
 
+    /**
+     * Edit study item paremeters
+     * @param mixed $id Id of studt item
+     * @param mixed $conditions Conditions related to item (filters only)
+     * @param bool $continuationid Link to previous filter item to copy result from (not used)
+     * @return array
+     */
     public static function edit_studyitem($id, $conditions, $continuationid = false) {
 
         $o = studyitem::find_by_id($id);
@@ -599,6 +707,11 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Reposition study items in line, layer and/or slot
+     * @param mixed $resequence Array of item info [id, line_id, slot, layer]
+     * @return array Success/fail model
+     */
     public static function reorder_studyitems($resequence) {
         // Check for permissions to modify the studyplan.
         foreach ($resequence as $sq) {
@@ -632,6 +745,11 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Delete a studyitem
+     * @param mixed $id Id of study item to delete
+     * @return array Success/fail model
+     */
     public static function delete_studyitem($id) {
         $o = studyitem::find_by_id($id);
         webservicehelper::require_capabilities(self::CAP_EDIT, $o->context());
@@ -664,6 +782,12 @@ class studyplanservice extends \external_api {
         return studyitemconnection::structure();
     }
 
+    /**
+     * Connect two studylines
+     * @param mixed $fromid Originating item
+     * @param mixed $toid Target item
+     * @return array Success/fail model
+     */
     public static function connect_studyitems($fromid, $toid) {
         // Validate permissions.
         webservicehelper::require_capabilities(self::CAP_EDIT, studyitem::find_by_id($fromid)->context());
@@ -698,6 +822,12 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Disconnect two studylines
+     * @param mixed $fromid Originating item
+     * @param mixed $toid Target item
+     * @return array Success/fail model
+     */
     public static function disconnect_studyitems($fromid, $toid) {
         // Validate permissions.
         webservicehelper::require_capabilities(self::CAP_EDIT, studyitem::find_by_id($fromid)->context());
@@ -727,6 +857,10 @@ class studyplanservice extends \external_api {
         return new \external_multiple_structure(badgeinfo::editor_structure());
     }
 
+    /**
+     * List all available badges to drag into a studyplan page
+     * @return array
+     */
     public static function list_badges() {
         $systemcontext = webservicehelper::system_context();
 
@@ -770,6 +904,16 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+
+    /**
+     * Mark a gradable item for inclusion in the studyplan
+     * @param mixed $gradeid Id of gradable
+     * @param mixed $itemid Id of study item
+     * @param bool $include Include grade or not
+     * @param bool $required Mark grade as required or not
+     * @return array Success/Fail model
+     * 
+     */
     public static function include_grade($gradeid, $itemid, $include, $required = false) {
         global $USER;
 
@@ -810,6 +954,10 @@ class studyplanservice extends \external_api {
         return aggregator::list_structure();
     }
 
+    /**
+     * List available aggregators
+     * @return array
+     */
     public static function list_aggregators() {
         return aggregator::list_model();
 
@@ -847,7 +995,13 @@ class studyplanservice extends \external_api {
         ]));
     }
 
-    public static function force_studyplan_scale($studyplanid, $scaleid) {
+    /**
+     * Force all gradables in the studyplan to the same scale item
+     * @param int $studyplanid Id of studyplan
+     * @param int $scaleid Id of scale to use
+     * @return array
+     */
+        public static function force_studyplan_scale($studyplanid, $scaleid) {
         global $DB;
         $dbman = $DB->get_manager();
 
@@ -967,6 +1121,10 @@ class studyplanservice extends \external_api {
         ]));
     }
 
+    /**
+     * List available scales
+     * @return array
+     */
     public static function list_scales() {
         global $DB;
         $list = [];
@@ -1007,6 +1165,11 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Disable automatic end date for all courses in a study plan
+     * @param int $studyplanid Id of the studyplan
+     * @return array Success/fail model
+     */
     public static function disable_autoenddate($studyplanid) {
         global $DB;
 
@@ -1060,6 +1223,13 @@ class studyplanservice extends \external_api {
         return studyplan::simple_structure();
     }
 
+    /**
+     * Duplicate a studyplan into a new one
+     * @param mixed $studyplanid Id of the plan to duplicate
+     * @param mixed $name New fullname
+     * @param mixed $shortname New shortname
+     * @return array
+     */
     public static function duplicate_plan($studyplanid, $name, $shortname) {
         // Validate permissions.
         webservicehelper::require_capabilities(self::CAP_EDIT, studyplan::find_by_id($studyplanid)->context());
@@ -1092,6 +1262,13 @@ class studyplanservice extends \external_api {
         return studyplan::export_structure();
     }
 
+    
+    /**
+     * Export studyplan 
+     * @param mixed $studyplanid Id of studyplan to export
+     * @param string $format Export format [csv, json (default)]
+     * @return array
+     */
     public static function export_plan($studyplanid, $format = "json") {
         try {
             // Validate permissions.
@@ -1127,9 +1304,12 @@ class studyplanservice extends \external_api {
         return studyplan::export_structure();
     }
 
+    /**
+     * Export studylines for a studyplan
+     * @param mixed $studyplanid Id of the studyplan to export the studylines for
+     * @return array
+     */
     public static function export_studylines($studyplanid) {
-        $systemcontext = webservicehelper::system_context();
-
         try {
             webservicehelper::require_capabilities(self::CAP_EDIT, studyplan::find_by_id($studyplanid)->context());
             $plan = studyplan::find_by_id($studyplanid);
@@ -1165,6 +1345,13 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Import studyplan from file
+     * @param string $content Content of file 
+     * @param string $format Format of file
+     * @param int $contextid ID of context to import to
+     * @return array Success/fail model
+     */
     public static function import_plan($content, $format = "application/json", $contextid = 1) {
 
         try {
@@ -1199,8 +1386,14 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
+    /**
+     * Import studylines into existing studtplan
+     * @param int $studyplanid ID of studyplan to import to
+     * @param string $content Content of file 
+     * @param string $format Format of file
+     * @return array Success/fail model
+     */
     public static function import_studylines($studyplanid, $content, $format = "application/json") {
-
         try {
             $plan = studyplan::find_by_id($studyplanid);
             // Validate import context.
@@ -1241,7 +1434,13 @@ class studyplanservice extends \external_api {
         return success::structure();
     }
 
-    /** DEPRECATED, will remove hacked edit form in the future */
+    /**
+     * Submit hacked course activity edit form to edit just name and description
+     * @deprecated will remove hacked edit form in the future 
+     * @param mixed $cmid
+     * @param mixed $formdata
+     * @return array Success/fail structure
+     */
     public static function submit_cm_editform($cmid, $formdata) {
         global $CFG;
         global $DB;
@@ -1329,6 +1528,15 @@ class studyplanservice extends \external_api {
         return period::structure();
     }
 
+    /**
+     * Edit period information
+     * @param mixed $id
+     * @param mixed $fullname
+     * @param mixed $shortname
+     * @param mixed $startdate
+     * @param mixed $enddate
+     * @return array
+     */
     public static function edit_period($id, $fullname, $shortname, $startdate, $enddate) {
 
         $p = period::find_by_id($id);
@@ -1370,6 +1578,13 @@ class studyplanservice extends \external_api {
         return courseinfo::editor_structure();
     }
 
+    /**
+     * Match course start/end to period start/end times
+     * @param mixed $periodid
+     * @param mixed $courseid
+     * @param int $span
+     * @return array
+     */
     public static function course_period_timing($periodid, $courseid, $span = 1) {
         global $DB;
         $period = period::find_by_id($periodid);
@@ -1442,6 +1657,12 @@ class studyplanservice extends \external_api {
         return studyitem::editor_structure();
     }
 
+    /**
+     * Set studyitem span to one or more periods
+     * @param mixed $id
+     * @param null $span
+     * @return array
+     */
     public static function set_studyitem_span($id, $span = null) {
         $o = studyitem::find_by_id($id);
         webservicehelper::require_capabilities(self::CAP_EDIT, $o->context());
diff --git a/classes/success.php b/classes/success.php
index b9d801d..d4d0158 100644
--- a/classes/success.php
+++ b/classes/success.php
@@ -68,7 +68,7 @@ class success {
 
     /**
      * Describe the result for the webservice model
-     * @return external_single_structure
+     * @return \external_description
      */
     public static function structure() {
         return new \external_single_structure([