diff --git a/src/pocketmine/inventory/FurnaceRecipe.php b/src/pocketmine/inventory/FurnaceRecipe.php
index 0216e2749..b52a2c36b 100644
--- a/src/pocketmine/inventory/FurnaceRecipe.php
+++ b/src/pocketmine/inventory/FurnaceRecipe.php
@@ -29,6 +29,7 @@ use pocketmine\utils\UUID;
 
 class FurnaceRecipe implements Recipe{
 
+	/** @var UUID|null */
 	private $id = null;
 
 	/** @var Item */
@@ -46,10 +47,16 @@ class FurnaceRecipe implements Recipe{
 		$this->ingredient = clone $ingredient;
 	}
 
+	/**
+	 * @return UUID|null
+	 */
 	public function getId(){
 		return $this->id;
 	}
 
+	/**
+	 * @param UUID $id
+	 */
 	public function setId(UUID $id){
 		if($this->id !== null){
 			throw new \InvalidStateException("Id is already set");
@@ -68,14 +75,14 @@ class FurnaceRecipe implements Recipe{
 	/**
 	 * @return Item
 	 */
-	public function getInput(){
+	public function getInput() : Item{
 		return clone $this->ingredient;
 	}
 
 	/**
 	 * @return Item
 	 */
-	public function getResult(){
+	public function getResult() : Item{
 		return clone $this->output;
 	}
 
diff --git a/src/pocketmine/inventory/Recipe.php b/src/pocketmine/inventory/Recipe.php
index 34f3d9f55..4328a5ff7 100644
--- a/src/pocketmine/inventory/Recipe.php
+++ b/src/pocketmine/inventory/Recipe.php
@@ -31,14 +31,17 @@ interface Recipe{
 	/**
 	 * @return Item
 	 */
-	public function getResult();
+	public function getResult() : Item;
 
 	public function registerToCraftingManager();
 
 	/**
-	 * @return UUID
+	 * @return UUID|null
 	 */
 	public function getId();
 
+	/**
+	 * @param UUID $id
+	 */
 	public function setId(UUID $id);
 }
\ No newline at end of file
diff --git a/src/pocketmine/inventory/ShapedRecipe.php b/src/pocketmine/inventory/ShapedRecipe.php
index 71cf21da6..d8a65876a 100644
--- a/src/pocketmine/inventory/ShapedRecipe.php
+++ b/src/pocketmine/inventory/ShapedRecipe.php
@@ -32,6 +32,7 @@ class ShapedRecipe implements Recipe{
 	/** @var Item */
 	private $output;
 
+	/** @var UUID|null */
 	private $id = null;
 
 	/** @var string[] */
@@ -49,7 +50,7 @@ class ShapedRecipe implements Recipe{
 	 *
 	 * @throws \Exception
 	 */
-	public function __construct(Item $result, $height, $width){
+	public function __construct(Item $result, int $height, int $width){
 		for($h = 0; $h < $height; $h++){
 			if($width === 0 or $width > 3){
 				throw new \InvalidStateException("Crafting rows should be 1, 2, 3 wide, not $width");
@@ -60,18 +61,24 @@ class ShapedRecipe implements Recipe{
 		$this->output = clone $result;
 	}
 
-	public function getWidth(){
+	public function getWidth() : int{
 		return count($this->ingredients[0]);
 	}
 
-	public function getHeight(){
+	public function getHeight() : int{
 		return count($this->ingredients);
 	}
 
-	public function getResult(){
+	/**
+	 * @return Item
+	 */
+	public function getResult() : Item{
 		return $this->output;
 	}
 
+	/**
+	 * @return UUID|null
+	 */
 	public function getId(){
 		return $this->id;
 	}
@@ -84,7 +91,14 @@ class ShapedRecipe implements Recipe{
 		$this->id = $id;
 	}
 
-	public function addIngredient($x, $y, Item $item){
+	/**
+	 * @param int $x
+	 * @param int $y
+	 * @param Item $item
+	 *
+	 * @return $this
+	 */
+	public function addIngredient(int $x, int $y, Item $item){
 		$this->ingredients[$y][$x] = clone $item;
 		return $this;
 	}
@@ -96,7 +110,7 @@ class ShapedRecipe implements Recipe{
 	 * @return $this
 	 * @throws \Exception
 	 */
-	public function setIngredient($key, Item $item){
+	public function setIngredient(string $key, Item $item){
 		if(!array_key_exists($key, $this->shape)){
 			throw new \Exception("Symbol does not appear in the shape: " . $key);
 		}
@@ -106,7 +120,11 @@ class ShapedRecipe implements Recipe{
 		return $this;
 	}
 
-	protected function fixRecipe($key, $item){
+	/**
+	 * @param string $key
+	 * @param Item $item
+	 */
+	protected function fixRecipe(string $key, Item $item){
 		foreach($this->shapeItems[$key] as $entry){
 			$this->ingredients[$entry->y][$entry->x] = clone $item;
 		}
@@ -115,7 +133,7 @@ class ShapedRecipe implements Recipe{
 	/**
 	 * @return Item[][]
 	 */
-	public function getIngredientMap(){
+	public function getIngredientMap() : array{
 		$ingredients = [];
 		foreach($this->ingredients as $y => $row){
 			$ingredients[$y] = [];
@@ -132,18 +150,19 @@ class ShapedRecipe implements Recipe{
 	}
 
 	/**
-	 * @param $x
-	 * @param $y
-	 * @return null|Item
+	 * @param int $x
+	 * @param int $y
+	 *
+	 * @return Item
 	 */
-	public function getIngredient($x, $y){
+	public function getIngredient(int $x, int $y){
 		return $this->ingredients[$y][$x] ?? Item::get(Item::AIR);
 	}
 
 	/**
 	 * @return string[]
 	 */
-	public function getShape(){
+	public function getShape() : array{
 		return $this->shape;
 	}
 
diff --git a/src/pocketmine/inventory/ShapelessRecipe.php b/src/pocketmine/inventory/ShapelessRecipe.php
index 91a867cb0..66cb7e4e3 100644
--- a/src/pocketmine/inventory/ShapelessRecipe.php
+++ b/src/pocketmine/inventory/ShapelessRecipe.php
@@ -31,6 +31,7 @@ class ShapelessRecipe implements Recipe{
 	/** @var Item */
 	private $output;
 
+	/** @var UUID|null */
 	private $id = null;
 
 	/** @var Item[] */
@@ -40,10 +41,16 @@ class ShapelessRecipe implements Recipe{
 		$this->output = clone $result;
 	}
 
+	/**
+	 * @return UUID|null
+	 */
 	public function getId(){
 		return $this->id;
 	}
 
+	/**
+	 * @param UUID $id
+	 */
 	public function setId(UUID $id){
 		if($this->id !== null){
 			throw new \InvalidStateException("Id is already set");
@@ -52,14 +59,14 @@ class ShapelessRecipe implements Recipe{
 		$this->id = $id;
 	}
 
-	public function getResult(){
+	public function getResult() : Item{
 		return clone $this->output;
 	}
 
 	/**
 	 * @param Item $item
 	 *
-	 * @returns ShapelessRecipe
+	 * @return ShapelessRecipe
 	 *
 	 * @throws \InvalidArgumentException
 	 */
@@ -101,7 +108,7 @@ class ShapelessRecipe implements Recipe{
 	/**
 	 * @return Item[]
 	 */
-	public function getIngredientList(){
+	public function getIngredientList() : array{
 		$ingredients = [];
 		foreach($this->ingredients as $ingredient){
 			$ingredients[] = clone $ingredient;
@@ -113,7 +120,7 @@ class ShapelessRecipe implements Recipe{
 	/**
 	 * @return int
 	 */
-	public function getIngredientCount(){
+	public function getIngredientCount() : int{
 		$count = 0;
 		foreach($this->ingredients as $ingredient){
 			$count += $ingredient->getCount();