diff --git a/bl-kernel/ajax/delete-image.php b/bl-kernel/ajax/delete-image.php
index ef152e5e..0135a6ad 100644
--- a/bl-kernel/ajax/delete-image.php
+++ b/bl-kernel/ajax/delete-image.php
@@ -5,7 +5,7 @@ header('Content-Type: application/json');
 | Delete an image from a particular page
 |
 | @_POST['filename']	string	Name of the file to delete
-| @_POST['uuid']	string	Page uuid
+| @_POST['uuid']	string	Page UUID
 |
 | @return	array
 */
diff --git a/bl-kernel/ajax/generate-slug.php b/bl-kernel/ajax/generate-slug.php
index 4db1b473..df0039b3 100644
--- a/bl-kernel/ajax/generate-slug.php
+++ b/bl-kernel/ajax/generate-slug.php
@@ -1,9 +1,22 @@
 <?php defined('BLUDIT') or die('Bludit CMS.');
 header('Content-Type: application/json');
 
+/*
+| Generate an slug text for the URL
+|
+| @_POST['text']	string 	The text from where is generated the slug
+| @_POST['parentKey']	string	The parent key if the page has one
+| @_POST['currentKey']	string	The current page key
+|
+| @return	array
+*/
+
+// $_POST
+// ----------------------------------------------------------------------------
 $text 	= isset($_POST['text']) ? $_POST['text'] : '';
 $parent = isset($_POST['parentKey']) ? $_POST['parentKey'] : '';
 $oldKey = isset($_POST['currentKey']) ? $_POST['currentKey'] : '';
+// ----------------------------------------------------------------------------
 
 $slug = $pages->generateKey($text, $parent, $returnSlug=true, $oldKey);
 
diff --git a/bl-kernel/ajax/get-parents.php b/bl-kernel/ajax/get-parents.php
index 2064f4da..4bdf5d49 100644
--- a/bl-kernel/ajax/get-parents.php
+++ b/bl-kernel/ajax/get-parents.php
@@ -1,6 +1,14 @@
 <?php defined('BLUDIT') or die('Bludit CMS.');
 header('Content-Type: application/json');
 
+/*
+| Returns a list of pages are parent and match with the string in them titles
+|
+| @_POST['query']	string 	The string to search in the title of the pages
+|
+| @return	array
+*/
+
 // $_GET
 // ----------------------------------------------------------------------------
 // (string) $_GET['query']
diff --git a/bl-kernel/ajax/list-images.php b/bl-kernel/ajax/list-images.php
index 525844c5..7f608ff8 100644
--- a/bl-kernel/ajax/list-images.php
+++ b/bl-kernel/ajax/list-images.php
@@ -2,11 +2,11 @@
 header('Content-Type: application/json');
 
 /*
-| List filename of image from a particular page
+| Returns a list of images from a particular page
 |
 | @_POST['pageNumber']	int	Page number for the paginator
 | @_POST['path']	string	Pre-defined name for the directory to read, its pre-defined to avoid security issues
-| @_POST['uuid']	string	Page uuid
+| @_POST['uuid']	string	Page UUID
 |
 | @return	array
 */
diff --git a/bl-kernel/ajax/logo-upload.php b/bl-kernel/ajax/logo-upload.php
index 180fede2..7853d1c4 100644
--- a/bl-kernel/ajax/logo-upload.php
+++ b/bl-kernel/ajax/logo-upload.php
@@ -1,6 +1,15 @@
 <?php defined('BLUDIT') or die('Bludit CMS.');
 header('Content-Type: application/json');
 
+/*
+| Upload site logo
+| The final filename is the site's name and the extension is the same as the file uploaded
+|
+| @_FILES['inputFile']	multipart/form-data	File from form
+|
+| @return	array
+*/
+
 if (!isset($_FILES['inputFile'])) {
 	ajaxResponse(1, 'Error trying to upload the site logo.');
 }
@@ -9,7 +18,9 @@ if (!isset($_FILES['inputFile'])) {
 $fileExtension = Filesystem::extension($_FILES['inputFile']['name']);
 $fileExtension = Text::lowercase($fileExtension);
 if (!in_array($fileExtension, ALLOWED_IMG_EXTENSION) ) {
-	return false;
+	$message = 'File type is not supported. Allowed types: '.implode(', ',ALLOWED_IMG_EXTENSION);
+	Log::set($message, LOG_TYPE_ERROR);
+	ajaxResponse(1, $message);
 }
 
 // Final filename
diff --git a/bl-kernel/ajax/profile-picture-upload.php b/bl-kernel/ajax/profile-picture-upload.php
index 63bf6f21..c0e4fcdb 100644
--- a/bl-kernel/ajax/profile-picture-upload.php
+++ b/bl-kernel/ajax/profile-picture-upload.php
@@ -16,10 +16,10 @@ if (!isset($_FILES['profilePictureInputFile'])) {
 }
 
 // File extension
-$allowedExtensions = array('gif', 'png', 'jpg', 'jpeg', 'svg');
-$fileExtension = pathinfo($_FILES['profilePictureInputFile']['name'], PATHINFO_EXTENSION);
-if (!in_array($fileExtension, $allowedExtensions) ) {
-	$message = 'File type is not supported. Allowed types: '.implode(', ',$allowedExtensions);
+$fileExtension = Filesystem::extension($_FILES['profilePictureInputFile']['name']);
+$fileExtension = Text::lowercase($fileExtension);
+if (!in_array($fileExtension, ALLOWED_IMG_EXTENSION) ) {
+	$message = 'File type is not supported. Allowed types: '.implode(', ',ALLOWED_IMG_EXTENSION);
 	Log::set($message, LOG_TYPE_ERROR);
 	ajaxResponse(1, $message);
 }
diff --git a/bl-kernel/ajax/user-logged.php b/bl-kernel/ajax/user-logged.php
deleted file mode 100644
index 61456736..00000000
--- a/bl-kernel/ajax/user-logged.php
+++ /dev/null
@@ -1,24 +0,0 @@
-<?php defined('BLUDIT') or die('Bludit CMS.');
-header('Content-Type: application/json');
-
-/*
- *
- * This script check if the user is logged
- *
- */
-
-// Check UUID
-if ($login->isLogged()) {
-	exit (json_encode(array(
-		'status'=>1,
-		'message'=>'The user is logged.'
-	)));
-}
-
-exit (json_encode(array(
-	'status'=>0,
-	'message'=>'The user is NOT logged.'
-)));
-
-
-?>
\ No newline at end of file