diff --git a/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/api/client/keybinding/v1/KeyBindingHelper.java b/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/api/client/keybinding/v1/KeyBindingHelper.java
index 9569774f2..e87b50ff1 100644
--- a/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/api/client/keybinding/v1/KeyBindingHelper.java
+++ b/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/api/client/keybinding/v1/KeyBindingHelper.java
@@ -16,6 +16,8 @@
 
 package net.fabricmc.fabric.api.client.keybinding.v1;
 
+import java.util.Objects;
+
 import net.minecraft.client.option.KeyBinding;
 import net.minecraft.client.util.InputUtil;
 
@@ -23,14 +25,15 @@ import net.fabricmc.fabric.impl.client.keybinding.KeyBindingRegistryImpl;
 import net.fabricmc.fabric.mixin.client.keybinding.KeyBindingAccessor;
 
 /**
- * Helper for registering key bindings.
- *
- * <p>Helper class for {@link KeyBinding} for use by Fabric mods.</p>
+ * Helper for registering {@link KeyBinding}s.
  *
  * <pre>{@code
  * KeyBinding left = KeyBindingHelper.registerKeyBinding(new KeyBinding("key.example.left", InputUtil.Type.KEYSYM, GLFW.GLFW_KEY_P, "key.category.example"));
  * KeyBinding right = KeyBindingHelper.registerKeyBinding(new KeyBinding("key.example.right", InputUtil.Type.KEYSYM, GLFW.GLFW_KEY_U, "key.category.example"));
  * }</pre>
+ *
+ * @see KeyBinding
+ * @see net.minecraft.client.option.StickyKeyBinding
  */
 public final class KeyBindingHelper {
 	private KeyBindingHelper() {
@@ -41,8 +44,10 @@ public final class KeyBindingHelper {
 	 *
 	 * @param keyBinding the keybinding
 	 * @return the keybinding itself
+	 * @throws IllegalArgumentException when a key binding with the same ID is already registered
 	 */
 	public static KeyBinding registerKeyBinding(KeyBinding keyBinding) {
+		Objects.requireNonNull(keyBinding, "key binding cannot be null");
 		return KeyBindingRegistryImpl.registerKeyBinding(keyBinding);
 	}
 
diff --git a/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/impl/client/keybinding/KeyBindingRegistryImpl.java b/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/impl/client/keybinding/KeyBindingRegistryImpl.java
index 55b37f5c2..0a0c09bc6 100644
--- a/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/impl/client/keybinding/KeyBindingRegistryImpl.java
+++ b/fabric-key-binding-api-v1/src/client/java/net/fabricmc/fabric/impl/client/keybinding/KeyBindingRegistryImpl.java
@@ -28,7 +28,7 @@ import net.minecraft.client.option.KeyBinding;
 import net.fabricmc.fabric.mixin.client.keybinding.KeyBindingAccessor;
 
 public final class KeyBindingRegistryImpl {
-	private static final List<KeyBinding> moddedKeyBindings = new ReferenceArrayList<>(); // ArrayList with identity based comparisons for contains/remove/indexOf etc., required for correctly handling duplicate keybinds
+	private static final List<KeyBinding> MODDED_KEY_BINDINGS = new ReferenceArrayList<>(); // ArrayList with identity based comparisons for contains/remove/indexOf etc., required for correctly handling duplicate keybinds
 
 	private KeyBindingRegistryImpl() {
 	}
@@ -37,10 +37,6 @@ public final class KeyBindingRegistryImpl {
 		return KeyBindingAccessor.fabric_getCategoryMap();
 	}
 
-	private static boolean hasCategory(String categoryTranslationKey) {
-		return getCategoryMap().containsKey(categoryTranslationKey);
-	}
-
 	public static boolean addCategory(String categoryTranslationKey) {
 		Map<String, Integer> map = getCategoryMap();
 
@@ -55,19 +51,18 @@ public final class KeyBindingRegistryImpl {
 	}
 
 	public static KeyBinding registerKeyBinding(KeyBinding binding) {
-		for (KeyBinding existingKeyBindings : moddedKeyBindings) {
+		for (KeyBinding existingKeyBindings : MODDED_KEY_BINDINGS) {
 			if (existingKeyBindings == binding) {
-				throw null;
+				throw new IllegalArgumentException("Attempted to register a key binding twice: " + binding.getTranslationKey());
 			} else if (existingKeyBindings.getTranslationKey().equals(binding.getTranslationKey())) {
-				throw new RuntimeException("Attempted to register two key bindings with equal ID: " + binding.getTranslationKey() + "!");
+				throw new IllegalArgumentException("Attempted to register two key bindings with equal ID: " + binding.getTranslationKey() + "!");
 			}
 		}
 
-		if (!hasCategory(binding.getCategory())) {
-			addCategory(binding.getCategory());
-		}
-
-		return moddedKeyBindings.add(binding) ? binding : null;
+		// This will do nothing if the category already exists.
+		addCategory(binding.getCategory());
+		MODDED_KEY_BINDINGS.add(binding);
+		return binding;
 	}
 
 	/**
@@ -76,8 +71,8 @@ public final class KeyBindingRegistryImpl {
 	 */
 	public static KeyBinding[] process(KeyBinding[] keysAll) {
 		List<KeyBinding> newKeysAll = Lists.newArrayList(keysAll);
-		newKeysAll.removeAll(moddedKeyBindings);
-		newKeysAll.addAll(moddedKeyBindings);
+		newKeysAll.removeAll(MODDED_KEY_BINDINGS);
+		newKeysAll.addAll(MODDED_KEY_BINDINGS);
 		return newKeysAll.toArray(new KeyBinding[0]);
 	}
 }