diff --git a/core_commands/gamemode.go b/core_commands/gamemode.go
index 4aa2a3f..64b51bf 100644
--- a/core_commands/gamemode.go
+++ b/core_commands/gamemode.go
@@ -22,17 +22,8 @@ var gamemode_cmd = &commands.Command{
 	Name:                "gamemode",
 	RequiredPermissions: []string{"server.command.gamemode"},
 	Arguments: []commands.Argument{
-		{
-			Name:     "mode",
-			ParserID: 39,
-		},
-		{
-			Name:     "player",
-			ParserID: 6,
-			Properties: commands.Properties{
-				Flags: 0x02,
-			},
-		},
+		commands.NewGamemodeArgument("mode"),
+		commands.NewEntityArgument("player", commands.EntityPlayerOnly),
 	},
 	Execute: func(ctx commands.CommandContext) {
 		if len(ctx.Arguments) == 0 {
diff --git a/go.mod b/go.mod
index 1b8d241..e90fbec 100644
--- a/go.mod
+++ b/go.mod
@@ -9,7 +9,7 @@ require (
 
 require (
 	github.com/Shopify/go-lua v0.0.0-20221004153744-91867de107cf
-	github.com/aimjel/minecraft v0.0.0-20230927182639-1fa3dd7aeebc
+	github.com/aimjel/minecraft v0.0.0-20230927222750-0a432da348ec
 	github.com/dop251/goja v0.0.0-20230919151941-fc55792775de
 )
 
diff --git a/go.sum b/go.sum
index 460ae7b..f0d8bd8 100644
--- a/go.sum
+++ b/go.sum
@@ -8,6 +8,8 @@ github.com/aimjel/minecraft v0.0.0-20230927163915-b3907034c0a8 h1:Vl58C0lpKTDgSZ
 github.com/aimjel/minecraft v0.0.0-20230927163915-b3907034c0a8/go.mod h1:/Y9/YBqxNOU7IFInEjDbsCVkdPNYJCPxC26jK+w3Phc=
 github.com/aimjel/minecraft v0.0.0-20230927182639-1fa3dd7aeebc h1:irjh4/oH9vWvkOr8xyQGudFeOYVpuzy9dgDnTkevtvg=
 github.com/aimjel/minecraft v0.0.0-20230927182639-1fa3dd7aeebc/go.mod h1:/Y9/YBqxNOU7IFInEjDbsCVkdPNYJCPxC26jK+w3Phc=
+github.com/aimjel/minecraft v0.0.0-20230927222750-0a432da348ec h1:aFUC1sZUBSlOtIniOxDWN2orepj9/dSxSAdqVtdVNcE=
+github.com/aimjel/minecraft v0.0.0-20230927222750-0a432da348ec/go.mod h1:/Y9/YBqxNOU7IFInEjDbsCVkdPNYJCPxC26jK+w3Phc=
 github.com/chzyer/logex v1.2.0/go.mod h1:9+9sk7u7pGNWYMkh0hdiL++6OeibzJccyQU4p4MedaY=
 github.com/chzyer/readline v1.5.0/go.mod h1:x22KAscuvRqlLoK9CsoYsmxoXZMMFVyOl86cAH8qUic=
 github.com/chzyer/test v0.0.0-20210722231415-061457976a23/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
diff --git a/server/commands/builders.go b/server/commands/builders.go
index 6a4f98f..706b238 100644
--- a/server/commands/builders.go
+++ b/server/commands/builders.go
@@ -6,14 +6,17 @@ const (
 	StringGreedyPhrase
 )
 
-func NewCommand(name string, execute func(ctx CommandContext), arguments ...Argument) *Command {
-	return &Command{Name: name, Execute: execute, Arguments: arguments}
-}
+const (
+	EntitySingle = iota + 1
+	EntityPlayerOnly
+)
 
 func NewBoolArgument(name string) Argument {
 	return Argument{
-		Name:     name,
-		ParserID: 0,
+		Name: name,
+		Parser: Parser{
+			ID: 0,
+		},
 	}
 }
 
@@ -31,9 +34,11 @@ func NewFloatArgument(name string, properties struct {
 		props.Max = *properties.Max
 	}
 	return Argument{
-		Name:       name,
-		ParserID:   1,
-		Properties: props,
+		Name: name,
+		Parser: Parser{
+			ID:         1,
+			Properties: props,
+		},
 	}
 }
 
@@ -51,9 +56,11 @@ func NewDoubleArgument(name string, properties struct {
 		props.Max = *properties.Max
 	}
 	return Argument{
-		Name:       name,
-		ParserID:   2,
-		Properties: props,
+		Name: name,
+		Parser: Parser{
+			ID:         2,
+			Properties: props,
+		},
 	}
 }
 
@@ -71,9 +78,11 @@ func NewIntegerArgument(name string, properties struct {
 		props.Max = uint64(*properties.Max)
 	}
 	return Argument{
-		Name:       name,
-		ParserID:   3,
-		Properties: props,
+		Name: name,
+		Parser: Parser{
+			ID:         3,
+			Properties: props,
+		},
 	}
 }
 
@@ -91,17 +100,41 @@ func NewLongArgument(name string, properties struct {
 		props.Max = uint64(*properties.Max)
 	}
 	return Argument{
-		Name:       name,
-		ParserID:   4,
-		Properties: props,
+		Name: name,
+		Parser: Parser{
+			ID:         4,
+			Properties: props,
+		},
 	}
 }
 
 func NewStringArgument(name string, properties byte) Argument {
 	props := Properties{Flags: properties}
 	return Argument{
-		Name:       name,
-		ParserID:   5,
-		Properties: props,
+		Name: name,
+		Parser: Parser{
+			ID:         5,
+			Properties: props,
+		},
+	}
+}
+
+func NewEntityArgument(name string, properties byte) Argument {
+	props := Properties{Flags: properties}
+	return Argument{
+		Name: name,
+		Parser: Parser{
+			ID:         6,
+			Properties: props,
+		},
+	}
+}
+
+func NewGamemodeArgument(name string) Argument {
+	return Argument{
+		Name: name,
+		Parser: Parser{
+			ID: 39,
+		},
 	}
 }
diff --git a/server/commands/commands.go b/server/commands/commands.go
index 84feaf2..762bead 100644
--- a/server/commands/commands.go
+++ b/server/commands/commands.go
@@ -54,16 +54,20 @@ type Command struct {
 }
 
 type Properties struct {
-	Flags      uint8  `json:",omitempty"`
-	Min, Max   uint64 `json:",omitempty"`
-	Identifier string `json:",omitempty"`
+	Flags      uint8
+	Min, Max   uint64
+	Identifier string
+}
+
+type Parser struct {
+	ID         int32      `js:"id"`
+	Properties Properties `js:"properties"`
 }
 
 type Argument struct {
 	Name           string `js:"name"`
-	ParserID       int32  `js:"parserId"`
 	SuggestionType string `js:"suggestionType"`
-	Properties     Properties
+	Parser         Parser `js:"parser"`
 }
 
 type Graph struct {
@@ -110,7 +114,7 @@ func (graph Graph) Data() *pk.DeclareCommands {
 		for _, argument := range command.Arguments {
 			parent := len(packet.Nodes) - 1
 			packet.Nodes[parent].Children = append(packet.Nodes[parent].Children, int32(len(packet.Nodes)))
-			node := pk.Node{Flags: 2, Name: argument.Name, Properties: argument.Properties, ParserID: argument.ParserID}
+			node := pk.Node{Flags: 2, Name: argument.Name, Properties: argument.Parser.Properties, ParserID: argument.Parser.ID}
 			if argument.SuggestionType != "" {
 				node.Flags |= 0x10
 				node.SuggestionsType = argument.SuggestionType