diff --git a/src/pocketmine/command/defaults/BanCommand.php b/src/pocketmine/command/defaults/BanCommand.php
index 4ace5acb6..6eb24ad1d 100644
--- a/src/pocketmine/command/defaults/BanCommand.php
+++ b/src/pocketmine/command/defaults/BanCommand.php
@@ -31,7 +31,7 @@ use pocketmine\Player;
 
 class BanCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.ban.player.description",
diff --git a/src/pocketmine/command/defaults/BanIpCommand.php b/src/pocketmine/command/defaults/BanIpCommand.php
index b6ccb496c..add40c482 100644
--- a/src/pocketmine/command/defaults/BanIpCommand.php
+++ b/src/pocketmine/command/defaults/BanIpCommand.php
@@ -31,7 +31,7 @@ use pocketmine\Player;
 
 class BanIpCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.ban.ip.description",
@@ -71,7 +71,7 @@ class BanIpCommand extends VanillaCommand{
 		return true;
 	}
 
-	private function processIPBan($ip, CommandSender $sender, $reason){
+	private function processIPBan(string $ip, CommandSender $sender, string $reason){
 		$sender->getServer()->getIPBans()->addBan($ip, $reason, null, $sender->getName());
 
 		foreach($sender->getServer()->getOnlinePlayers() as $player){
diff --git a/src/pocketmine/command/defaults/BanListCommand.php b/src/pocketmine/command/defaults/BanListCommand.php
index b609abf3a..064c777f7 100644
--- a/src/pocketmine/command/defaults/BanListCommand.php
+++ b/src/pocketmine/command/defaults/BanListCommand.php
@@ -30,7 +30,7 @@ use pocketmine\permission\BanEntry;
 
 class BanListCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.banlist.description",
diff --git a/src/pocketmine/command/defaults/DefaultGamemodeCommand.php b/src/pocketmine/command/defaults/DefaultGamemodeCommand.php
index be4539aa2..3bd0fd617 100644
--- a/src/pocketmine/command/defaults/DefaultGamemodeCommand.php
+++ b/src/pocketmine/command/defaults/DefaultGamemodeCommand.php
@@ -30,7 +30,7 @@ use pocketmine\Server;
 
 class DefaultGamemodeCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.defaultgamemode.description",
diff --git a/src/pocketmine/command/defaults/DeopCommand.php b/src/pocketmine/command/defaults/DeopCommand.php
index 9f71fb91a..c8523921f 100644
--- a/src/pocketmine/command/defaults/DeopCommand.php
+++ b/src/pocketmine/command/defaults/DeopCommand.php
@@ -32,7 +32,7 @@ use pocketmine\utils\TextFormat;
 
 class DeopCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.deop.description",
diff --git a/src/pocketmine/command/defaults/DifficultyCommand.php b/src/pocketmine/command/defaults/DifficultyCommand.php
index b11832f34..5b8cae9d6 100644
--- a/src/pocketmine/command/defaults/DifficultyCommand.php
+++ b/src/pocketmine/command/defaults/DifficultyCommand.php
@@ -32,7 +32,7 @@ use pocketmine\Server;
 
 class DifficultyCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.difficulty.description",
diff --git a/src/pocketmine/command/defaults/DumpMemoryCommand.php b/src/pocketmine/command/defaults/DumpMemoryCommand.php
index 593533ea1..ccdd3055a 100644
--- a/src/pocketmine/command/defaults/DumpMemoryCommand.php
+++ b/src/pocketmine/command/defaults/DumpMemoryCommand.php
@@ -29,7 +29,7 @@ class DumpMemoryCommand extends VanillaCommand{
 
 	private static $executions = 0;
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"Dumps the memory",
diff --git a/src/pocketmine/command/defaults/EffectCommand.php b/src/pocketmine/command/defaults/EffectCommand.php
index 51b185d69..6efcbb5d0 100644
--- a/src/pocketmine/command/defaults/EffectCommand.php
+++ b/src/pocketmine/command/defaults/EffectCommand.php
@@ -31,7 +31,7 @@ use pocketmine\utils\TextFormat;
 
 class EffectCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.effect.description",
diff --git a/src/pocketmine/command/defaults/EnchantCommand.php b/src/pocketmine/command/defaults/EnchantCommand.php
index 40fcf6fdf..9c1051f1c 100644
--- a/src/pocketmine/command/defaults/EnchantCommand.php
+++ b/src/pocketmine/command/defaults/EnchantCommand.php
@@ -31,7 +31,7 @@ use pocketmine\utils\TextFormat;
 
 class EnchantCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.enchant.description",
diff --git a/src/pocketmine/command/defaults/GamemodeCommand.php b/src/pocketmine/command/defaults/GamemodeCommand.php
index 65c245f33..0efc305ab 100644
--- a/src/pocketmine/command/defaults/GamemodeCommand.php
+++ b/src/pocketmine/command/defaults/GamemodeCommand.php
@@ -33,7 +33,7 @@ use pocketmine\utils\TextFormat;
 
 class GamemodeCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.gamemode.description",
diff --git a/src/pocketmine/command/defaults/GarbageCollectorCommand.php b/src/pocketmine/command/defaults/GarbageCollectorCommand.php
index 526482d85..eca388788 100644
--- a/src/pocketmine/command/defaults/GarbageCollectorCommand.php
+++ b/src/pocketmine/command/defaults/GarbageCollectorCommand.php
@@ -28,7 +28,7 @@ use pocketmine\utils\TextFormat;
 
 class GarbageCollectorCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.gc.description",
diff --git a/src/pocketmine/command/defaults/GiveCommand.php b/src/pocketmine/command/defaults/GiveCommand.php
index 0e7036814..0124e8767 100644
--- a/src/pocketmine/command/defaults/GiveCommand.php
+++ b/src/pocketmine/command/defaults/GiveCommand.php
@@ -35,7 +35,7 @@ use pocketmine\utils\TextFormat;
 
 class GiveCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.give.description",
diff --git a/src/pocketmine/command/defaults/HelpCommand.php b/src/pocketmine/command/defaults/HelpCommand.php
index 8542847a9..bc7ca1353 100644
--- a/src/pocketmine/command/defaults/HelpCommand.php
+++ b/src/pocketmine/command/defaults/HelpCommand.php
@@ -30,7 +30,7 @@ use pocketmine\utils\TextFormat;
 
 class HelpCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.help.description",
diff --git a/src/pocketmine/command/defaults/KickCommand.php b/src/pocketmine/command/defaults/KickCommand.php
index 7368b4276..543d6f915 100644
--- a/src/pocketmine/command/defaults/KickCommand.php
+++ b/src/pocketmine/command/defaults/KickCommand.php
@@ -32,7 +32,7 @@ use pocketmine\utils\TextFormat;
 
 class KickCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.kick.description",
diff --git a/src/pocketmine/command/defaults/KillCommand.php b/src/pocketmine/command/defaults/KillCommand.php
index 1e772ae2d..74ee5ca60 100644
--- a/src/pocketmine/command/defaults/KillCommand.php
+++ b/src/pocketmine/command/defaults/KillCommand.php
@@ -33,7 +33,7 @@ use pocketmine\utils\TextFormat;
 
 class KillCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.kill.description",
diff --git a/src/pocketmine/command/defaults/ListCommand.php b/src/pocketmine/command/defaults/ListCommand.php
index edc483982..56526eb5b 100644
--- a/src/pocketmine/command/defaults/ListCommand.php
+++ b/src/pocketmine/command/defaults/ListCommand.php
@@ -29,7 +29,7 @@ use pocketmine\Player;
 
 class ListCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.list.description",
diff --git a/src/pocketmine/command/defaults/MeCommand.php b/src/pocketmine/command/defaults/MeCommand.php
index 380b7f93b..16fbc5ec7 100644
--- a/src/pocketmine/command/defaults/MeCommand.php
+++ b/src/pocketmine/command/defaults/MeCommand.php
@@ -31,7 +31,7 @@ use pocketmine\utils\TextFormat;
 
 class MeCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.me.description",
diff --git a/src/pocketmine/command/defaults/OpCommand.php b/src/pocketmine/command/defaults/OpCommand.php
index 0000f8410..bec3ba92f 100644
--- a/src/pocketmine/command/defaults/OpCommand.php
+++ b/src/pocketmine/command/defaults/OpCommand.php
@@ -32,7 +32,7 @@ use pocketmine\utils\TextFormat;
 
 class OpCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.op.description",
diff --git a/src/pocketmine/command/defaults/PardonCommand.php b/src/pocketmine/command/defaults/PardonCommand.php
index c0b97ae7d..406745d6c 100644
--- a/src/pocketmine/command/defaults/PardonCommand.php
+++ b/src/pocketmine/command/defaults/PardonCommand.php
@@ -30,7 +30,7 @@ use pocketmine\event\TranslationContainer;
 
 class PardonCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.unban.player.description",
diff --git a/src/pocketmine/command/defaults/PardonIpCommand.php b/src/pocketmine/command/defaults/PardonIpCommand.php
index cfe7571ed..18e9c6679 100644
--- a/src/pocketmine/command/defaults/PardonIpCommand.php
+++ b/src/pocketmine/command/defaults/PardonIpCommand.php
@@ -30,7 +30,7 @@ use pocketmine\event\TranslationContainer;
 
 class PardonIpCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.unban.ip.description",
diff --git a/src/pocketmine/command/defaults/ParticleCommand.php b/src/pocketmine/command/defaults/ParticleCommand.php
index a11c6ae15..dba99fc59 100644
--- a/src/pocketmine/command/defaults/ParticleCommand.php
+++ b/src/pocketmine/command/defaults/ParticleCommand.php
@@ -64,7 +64,7 @@ use pocketmine\utils\TextFormat;
 
 class ParticleCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.particle.description",
@@ -126,7 +126,6 @@ class ParticleCommand extends VanillaCommand{
 
 	/**
 	 * @param string   $name
-	 *
 	 * @param Vector3  $pos
 	 * @param float    $xd
 	 * @param float    $yd
@@ -135,7 +134,7 @@ class ParticleCommand extends VanillaCommand{
 	 *
 	 * @return Particle|null
 	 */
-	private function getParticle($name, Vector3 $pos, $xd, $yd, $zd, $data){
+	private function getParticle(string $name, Vector3 $pos, float $xd, float $yd, float $zd, int $data = null){
 		switch($name){
 			case "explode":
 				return new ExplodeParticle($pos);
diff --git a/src/pocketmine/command/defaults/PluginsCommand.php b/src/pocketmine/command/defaults/PluginsCommand.php
index a43d06d29..e93281100 100644
--- a/src/pocketmine/command/defaults/PluginsCommand.php
+++ b/src/pocketmine/command/defaults/PluginsCommand.php
@@ -29,7 +29,7 @@ use pocketmine\utils\TextFormat;
 
 class PluginsCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.plugins.description",
diff --git a/src/pocketmine/command/defaults/ReloadCommand.php b/src/pocketmine/command/defaults/ReloadCommand.php
index 0097c30cb..b601c1932 100644
--- a/src/pocketmine/command/defaults/ReloadCommand.php
+++ b/src/pocketmine/command/defaults/ReloadCommand.php
@@ -30,7 +30,7 @@ use pocketmine\utils\TextFormat;
 
 class ReloadCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.reload.description",
diff --git a/src/pocketmine/command/defaults/SaveCommand.php b/src/pocketmine/command/defaults/SaveCommand.php
index 5631e99d6..81e6d5ba1 100644
--- a/src/pocketmine/command/defaults/SaveCommand.php
+++ b/src/pocketmine/command/defaults/SaveCommand.php
@@ -29,7 +29,7 @@ use pocketmine\event\TranslationContainer;
 
 class SaveCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.save.description",
diff --git a/src/pocketmine/command/defaults/SaveOffCommand.php b/src/pocketmine/command/defaults/SaveOffCommand.php
index 2aba6c39c..7917fa7e2 100644
--- a/src/pocketmine/command/defaults/SaveOffCommand.php
+++ b/src/pocketmine/command/defaults/SaveOffCommand.php
@@ -29,7 +29,7 @@ use pocketmine\event\TranslationContainer;
 
 class SaveOffCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.saveoff.description",
diff --git a/src/pocketmine/command/defaults/SaveOnCommand.php b/src/pocketmine/command/defaults/SaveOnCommand.php
index bfe8aff7e..044c41a84 100644
--- a/src/pocketmine/command/defaults/SaveOnCommand.php
+++ b/src/pocketmine/command/defaults/SaveOnCommand.php
@@ -29,7 +29,7 @@ use pocketmine\event\TranslationContainer;
 
 class SaveOnCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.saveon.description",
diff --git a/src/pocketmine/command/defaults/SayCommand.php b/src/pocketmine/command/defaults/SayCommand.php
index 16960b246..9055bc5e1 100644
--- a/src/pocketmine/command/defaults/SayCommand.php
+++ b/src/pocketmine/command/defaults/SayCommand.php
@@ -32,7 +32,7 @@ use pocketmine\utils\TextFormat;
 
 class SayCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.say.description",
diff --git a/src/pocketmine/command/defaults/SeedCommand.php b/src/pocketmine/command/defaults/SeedCommand.php
index 5d3edbcdf..34a4e4c0d 100644
--- a/src/pocketmine/command/defaults/SeedCommand.php
+++ b/src/pocketmine/command/defaults/SeedCommand.php
@@ -29,7 +29,7 @@ use pocketmine\Player;
 
 class SeedCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.seed.description",
diff --git a/src/pocketmine/command/defaults/SetWorldSpawnCommand.php b/src/pocketmine/command/defaults/SetWorldSpawnCommand.php
index 228dcf8fa..b1ac729af 100644
--- a/src/pocketmine/command/defaults/SetWorldSpawnCommand.php
+++ b/src/pocketmine/command/defaults/SetWorldSpawnCommand.php
@@ -33,7 +33,7 @@ use pocketmine\utils\TextFormat;
 
 class SetWorldSpawnCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.setworldspawn.description",
diff --git a/src/pocketmine/command/defaults/SpawnpointCommand.php b/src/pocketmine/command/defaults/SpawnpointCommand.php
index 9b35625ee..590f9b4cf 100644
--- a/src/pocketmine/command/defaults/SpawnpointCommand.php
+++ b/src/pocketmine/command/defaults/SpawnpointCommand.php
@@ -34,7 +34,7 @@ use pocketmine\utils\TextFormat;
 
 class SpawnpointCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.spawnpoint.description",
diff --git a/src/pocketmine/command/defaults/StatusCommand.php b/src/pocketmine/command/defaults/StatusCommand.php
index 621b90771..6142880d0 100644
--- a/src/pocketmine/command/defaults/StatusCommand.php
+++ b/src/pocketmine/command/defaults/StatusCommand.php
@@ -29,7 +29,7 @@ use pocketmine\utils\Utils;
 
 class StatusCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.status.description",
diff --git a/src/pocketmine/command/defaults/StopCommand.php b/src/pocketmine/command/defaults/StopCommand.php
index 67c66be90..36126307e 100644
--- a/src/pocketmine/command/defaults/StopCommand.php
+++ b/src/pocketmine/command/defaults/StopCommand.php
@@ -29,7 +29,7 @@ use pocketmine\event\TranslationContainer;
 
 class StopCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.stop.description",
diff --git a/src/pocketmine/command/defaults/TeleportCommand.php b/src/pocketmine/command/defaults/TeleportCommand.php
index 9eed0a972..cd0e42a7d 100644
--- a/src/pocketmine/command/defaults/TeleportCommand.php
+++ b/src/pocketmine/command/defaults/TeleportCommand.php
@@ -33,7 +33,7 @@ use pocketmine\utils\TextFormat;
 
 class TeleportCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.tp.description",
diff --git a/src/pocketmine/command/defaults/TellCommand.php b/src/pocketmine/command/defaults/TellCommand.php
index ab89cc422..4dccfda90 100644
--- a/src/pocketmine/command/defaults/TellCommand.php
+++ b/src/pocketmine/command/defaults/TellCommand.php
@@ -31,7 +31,7 @@ use pocketmine\utils\TextFormat;
 
 class TellCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.tell.description",
diff --git a/src/pocketmine/command/defaults/TimeCommand.php b/src/pocketmine/command/defaults/TimeCommand.php
index 8c7f1ccb1..3d5b17137 100644
--- a/src/pocketmine/command/defaults/TimeCommand.php
+++ b/src/pocketmine/command/defaults/TimeCommand.php
@@ -33,7 +33,7 @@ use pocketmine\utils\TextFormat;
 
 class TimeCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.time.description",
diff --git a/src/pocketmine/command/defaults/TimingsCommand.php b/src/pocketmine/command/defaults/TimingsCommand.php
index 584740a27..cfe1740b7 100644
--- a/src/pocketmine/command/defaults/TimingsCommand.php
+++ b/src/pocketmine/command/defaults/TimingsCommand.php
@@ -35,7 +35,7 @@ class TimingsCommand extends VanillaCommand{
 
 	public static $timingStart = 0;
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.timings.description",
diff --git a/src/pocketmine/command/defaults/TitleCommand.php b/src/pocketmine/command/defaults/TitleCommand.php
index 9f9b42ba4..0545cd9b3 100644
--- a/src/pocketmine/command/defaults/TitleCommand.php
+++ b/src/pocketmine/command/defaults/TitleCommand.php
@@ -29,7 +29,7 @@ use pocketmine\event\TranslationContainer;
 
 class TitleCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.title.description",
diff --git a/src/pocketmine/command/defaults/TransferServerCommand.php b/src/pocketmine/command/defaults/TransferServerCommand.php
index b4db230c4..86502b3a0 100644
--- a/src/pocketmine/command/defaults/TransferServerCommand.php
+++ b/src/pocketmine/command/defaults/TransferServerCommand.php
@@ -31,7 +31,7 @@ use pocketmine\Player;
 
 class TransferServerCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.transferserver.description",
diff --git a/src/pocketmine/command/defaults/VanillaCommand.php b/src/pocketmine/command/defaults/VanillaCommand.php
index 951893337..7b247acfd 100644
--- a/src/pocketmine/command/defaults/VanillaCommand.php
+++ b/src/pocketmine/command/defaults/VanillaCommand.php
@@ -30,11 +30,15 @@ abstract class VanillaCommand extends Command{
 	const MAX_COORD = 30000000;
 	const MIN_COORD = -30000000;
 
-	public function __construct($name, $description = "", $usageMessage = null, array $aliases = []){
-		parent::__construct($name, $description, $usageMessage, $aliases);
-	}
-
-	protected function getInteger(CommandSender $sender, $value, $min = self::MIN_COORD, $max = self::MAX_COORD){
+	/**
+	 * @param CommandSender $sender
+	 * @param mixed         $value
+	 * @param int           $min
+	 * @param int           $max
+	 *
+	 * @return int
+	 */
+	protected function getInteger(CommandSender $sender, $value, int $min = self::MIN_COORD, int $max = self::MAX_COORD) : int{
 		$i = (int) $value;
 
 		if($i < $min){
@@ -46,7 +50,16 @@ abstract class VanillaCommand extends Command{
 		return $i;
 	}
 
-	protected function getRelativeDouble($original, CommandSender $sender, $input, $min = self::MIN_COORD, $max = self::MAX_COORD){
+	/**
+	 * @param float         $original
+	 * @param CommandSender $sender
+	 * @param string        $input
+	 * @param float         $min
+	 * @param float         $max
+	 *
+	 * @return float
+	 */
+	protected function getRelativeDouble(float $original, CommandSender $sender, string $input, float $min = self::MIN_COORD, float $max = self::MAX_COORD) : float{
 		if($input{0} === "~"){
 			$value = $this->getDouble($sender, substr($input, 1));
 
@@ -56,7 +69,15 @@ abstract class VanillaCommand extends Command{
 		return $this->getDouble($sender, $input, $min, $max);
 	}
 
-	protected function getDouble(CommandSender $sender, $value, $min = self::MIN_COORD, $max = self::MAX_COORD){
+	/**
+	 * @param CommandSender $sender
+	 * @param mixed         $value
+	 * @param float         $min
+	 * @param float         $max
+	 *
+	 * @return float
+	 */
+	protected function getDouble(CommandSender $sender, $value, float $min = self::MIN_COORD, float $max = self::MAX_COORD) : float{
 		$i = (double) $value;
 
 		if($i < $min){
diff --git a/src/pocketmine/command/defaults/VersionCommand.php b/src/pocketmine/command/defaults/VersionCommand.php
index c3dba9064..257651765 100644
--- a/src/pocketmine/command/defaults/VersionCommand.php
+++ b/src/pocketmine/command/defaults/VersionCommand.php
@@ -31,7 +31,7 @@ use pocketmine\utils\TextFormat;
 
 class VersionCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.version.description",
diff --git a/src/pocketmine/command/defaults/WhitelistCommand.php b/src/pocketmine/command/defaults/WhitelistCommand.php
index a012508e2..89eedae3c 100644
--- a/src/pocketmine/command/defaults/WhitelistCommand.php
+++ b/src/pocketmine/command/defaults/WhitelistCommand.php
@@ -31,7 +31,7 @@ use pocketmine\utils\TextFormat;
 
 class WhitelistCommand extends VanillaCommand{
 
-	public function __construct($name){
+	public function __construct(string $name){
 		parent::__construct(
 			$name,
 			"%pocketmine.command.whitelist.description",
@@ -108,7 +108,7 @@ class WhitelistCommand extends VanillaCommand{
 		return true;
 	}
 
-	private function badPerm(CommandSender $sender, $perm){
+	private function badPerm(CommandSender $sender, string $perm) : bool{
 		if(!$sender->hasPermission("pocketmine.command.whitelist.$perm")){
 			$sender->sendMessage(new TranslationContainer(TextFormat::RED . "%commands.generic.permission"));