add descriptions.,,.

src/main/java/com/mojang/brigadier/builder/ArgumentBuilder.java

@@ -4,6 +4,7 @@
 package com.mojang.brigadier.builder;
 
 import com.mojang.brigadier.Command;
+import com.mojang.brigadier.Message;
 import com.mojang.brigadier.RedirectModifier;
 import com.mojang.brigadier.SingleRedirectModifier;
 import com.mojang.brigadier.tree.CommandNode;
@@ -20,6 +21,7 @@ public abstract class ArgumentBuilder<S, T extends ArgumentBuilder<S, T>> {
     private CommandNode<S> target;
     private RedirectModifier<S> modifier = null;
     private boolean forks;
+    private Message description;
 
     protected abstract T getThis();
 
@@ -52,6 +54,15 @@ public abstract class ArgumentBuilder<S, T extends ArgumentBuilder<S, T>> {
         return command;
     }
 
+    public T describe(final Message description) {
+        this.description = description;
+        return getThis();
+    }
+
+    public Message getDescription() {
+        return description;
+    }
+
     public T requires(final Predicate<S> requirement) {
         this.requirement = requirement;
         return getThis();

src/main/java/com/mojang/brigadier/builder/LiteralArgumentBuilder.java

@@ -28,7 +28,7 @@ public class LiteralArgumentBuilder<S> extends ArgumentBuilder<S, LiteralArgumen
 
     @Override
     public LiteralCommandNode<S> build() {
-        final LiteralCommandNode<S> result = new LiteralCommandNode<>(getLiteral(), getCommand(), getRequirement(), getRedirect(), getRedirectModifier(), isFork());
+        final LiteralCommandNode<S> result = new LiteralCommandNode<>(getLiteral(), getCommand(), getRequirement(), getRedirect(), getRedirectModifier(), isFork(), getDescription());
 
         for (final CommandNode<S> argument : getArguments()) {
             result.addChild(argument);

src/main/java/com/mojang/brigadier/builder/RequiredArgumentBuilder.java

@@ -45,7 +45,7 @@ public class RequiredArgumentBuilder<S, T> extends ArgumentBuilder<S, RequiredAr
     }
 
     public ArgumentCommandNode<S, T> build() {
-        final ArgumentCommandNode<S, T> result = new ArgumentCommandNode<>(getName(), getType(), getCommand(), getRequirement(), getRedirect(), getRedirectModifier(), isFork(), getSuggestionsProvider());
+        final ArgumentCommandNode<S, T> result = new ArgumentCommandNode<>(getName(), getType(), getCommand(), getRequirement(), getRedirect(), getRedirectModifier(), isFork(), getSuggestionsProvider(), getDescription());
 
         for (final CommandNode<S> argument : getArguments()) {
             result.addChild(argument);

src/main/java/com/mojang/brigadier/tree/ArgumentCommandNode.java

@@ -4,6 +4,7 @@
 package com.mojang.brigadier.tree;
 
 import com.mojang.brigadier.Command;
+import com.mojang.brigadier.Message;
 import com.mojang.brigadier.RedirectModifier;
 import com.mojang.brigadier.StringReader;
 import com.mojang.brigadier.arguments.ArgumentType;
@@ -29,7 +30,11 @@ public class ArgumentCommandNode<S, T> extends CommandNode<S> {
     private final SuggestionProvider<S> customSuggestions;
 
     public ArgumentCommandNode(final String name, final ArgumentType<T> type, final Command<S> command, final Predicate<S> requirement, final CommandNode<S> redirect, final RedirectModifier<S> modifier, final boolean forks, final SuggestionProvider<S> customSuggestions) {
-        super(command, requirement, redirect, modifier, forks);
+        this(name, type, command, requirement, redirect, modifier, forks, customSuggestions, null);
+    }
+
+    public ArgumentCommandNode(final String name, final ArgumentType<T> type, final Command<S> command, final Predicate<S> requirement, final CommandNode<S> redirect, final RedirectModifier<S> modifier, final boolean forks, final SuggestionProvider<S> customSuggestions, final Message description) {
+        super(command, requirement, redirect, modifier, forks, description);
         this.name = name;
         this.type = type;
         this.customSuggestions = customSuggestions;

src/main/java/com/mojang/brigadier/tree/CommandNode.java

@@ -3,10 +3,7 @@
 
 package com.mojang.brigadier.tree;
 
-import com.mojang.brigadier.AmbiguityConsumer;
+import com.mojang.brigadier.*;
-import com.mojang.brigadier.Command;
-import com.mojang.brigadier.RedirectModifier;
-import com.mojang.brigadier.StringReader;
 import com.mojang.brigadier.builder.ArgumentBuilder;
 import com.mojang.brigadier.context.CommandContext;
 import com.mojang.brigadier.context.CommandContextBuilder;
@@ -32,19 +29,29 @@ public abstract class CommandNode<S> implements Comparable<CommandNode<S>> {
     private final RedirectModifier<S> modifier;
     private final boolean forks;
     private Command<S> command;
+    private Message description;
 
     protected CommandNode(final Command<S> command, final Predicate<S> requirement, final CommandNode<S> redirect, final RedirectModifier<S> modifier, final boolean forks) {
+        this(command, requirement, redirect, modifier, forks, null);
+    }
+
+    protected CommandNode(final Command<S> command, final Predicate<S> requirement, final CommandNode<S> redirect, final RedirectModifier<S> modifier, final boolean forks, final Message description) {
         this.command = command;
         this.requirement = requirement;
         this.redirect = redirect;
         this.modifier = modifier;
         this.forks = forks;
+        this.description = description;
     }
 
     public Command<S> getCommand() {
         return command;
     }
 
+    public Message getDescription() {
+        return description;
+    }
+
     public Collection<CommandNode<S>> getChildren() {
         return children.values();
     }

src/main/java/com/mojang/brigadier/tree/LiteralCommandNode.java

@@ -4,6 +4,7 @@
 package com.mojang.brigadier.tree;
 
 import com.mojang.brigadier.Command;
+import com.mojang.brigadier.Message;
 import com.mojang.brigadier.RedirectModifier;
 import com.mojang.brigadier.StringReader;
 import com.mojang.brigadier.builder.LiteralArgumentBuilder;
@@ -25,7 +26,11 @@ public class LiteralCommandNode<S> extends CommandNode<S> {
     private final String literalLowerCase;
 
     public LiteralCommandNode(final String literal, final Command<S> command, final Predicate<S> requirement, final CommandNode<S> redirect, final RedirectModifier<S> modifier, final boolean forks) {
-        super(command, requirement, redirect, modifier, forks);
+        this(literal, command, requirement, redirect, modifier, forks, null);
+    }
+
+    public LiteralCommandNode(final String literal, final Command<S> command, final Predicate<S> requirement, final CommandNode<S> redirect, final RedirectModifier<S> modifier, final boolean forks, final Message description) {
+        super(command, requirement, redirect, modifier, forks, description);
         this.literal = literal;
         this.literalLowerCase = literal.toLowerCase(Locale.ROOT);
     }

src/main/java/com/mojang/brigadier/tree/RootCommandNode.java

@@ -17,7 +17,7 @@ import java.util.concurrent.CompletableFuture;
 
 public class RootCommandNode<S> extends CommandNode<S> {
     public RootCommandNode() {
-        super(null, c -> true, null, s -> Collections.singleton(s.getSource()), false);
+        super(null, c -> true, null, s -> Collections.singleton(s.getSource()), false, null);
     }
 
     @Override