# RecipeAddException > Thrown when a custom recipe fails to be added. `gg.lode.observerapi.api.exception` --- ## Signature ```java public class RecipeAddException extends Exception ``` ## Extends - `Exception` --- ## Nested Types ### Type ```java public enum Type ``` | Constant | Description | |----------|-------------| | `INVALID_NAMESPACED_KEY` | The provided namespaced key is invalid | | `ID_ALREADY_USED` | A recipe with this ID already exists | | `SERVER_REFUSED_RECIPE` | The server rejected the recipe registration | --- ## Constructor ```java public RecipeAddException(String message, Type type) ``` | Parameter | Type | Description | |-----------|------|-------------| | `message` | `String` | The error message | | `type` | `Type` | The type of failure | --- ## Methods ### type ```java public Type type() ``` **Returns:** `RecipeAddException.Type` - the type of failure that caused this exception --- ## Related Pages - [[ICustomRecipesManager]]