diff --git a/lib/lrama/grammar/binding.rb b/lib/lrama/grammar/binding.rb
index 5e528284..2efb918a 100644
--- a/lib/lrama/grammar/binding.rb
+++ b/lib/lrama/grammar/binding.rb
@@ -1,40 +1,57 @@
+# rbs_inline: enabled
 # frozen_string_literal: true
 
 module Lrama
   class Grammar
     class Binding
-      attr_reader :actual_args, :count
+      # @rbs @actual_args: Array[Lexer::Token]
+      # @rbs @param_to_arg: Hash[String, Lexer::Token]
 
-      def initialize(parameterizing_rule, actual_args)
-        @parameters = parameterizing_rule.parameters
+      # @rbs (Array[Lexer::Token] params, Array[Lexer::Token] actual_args) -> void
+      def initialize(params, actual_args)
         @actual_args = actual_args
-        @parameter_to_arg = @parameters.zip(actual_args).map do |param, arg|
-          [param.s_value, arg]
-        end.to_h
+        @param_to_arg = map_params_to_args(params, @actual_args)
       end
 
-      def resolve_symbol(symbol)
-        if symbol.is_a?(Lexer::Token::InstantiateRule)
-          resolved_args = symbol.args.map { |arg| resolve_symbol(arg) }
-          Lrama::Lexer::Token::InstantiateRule.new(s_value: symbol.s_value, location: symbol.location, args: resolved_args, lhs_tag: symbol.lhs_tag)
+      # @rbs (Lexer::Token sym) -> Lexer::Token
+      def resolve_symbol(sym)
+        if sym.is_a?(Lexer::Token::InstantiateRule)
+          Lrama::Lexer::Token::InstantiateRule.new(
+            s_value: sym.s_value, location: sym.location, args: resolved_args(sym), lhs_tag: sym.lhs_tag
+          )
         else
-          parameter_to_arg(symbol) || symbol
+          param_to_arg(sym)
         end
       end
 
+      # @rbs (Lexer::Token::InstantiateRule token) -> String
       def concatenated_args_str(token)
         "#{token.rule_name}_#{token_to_args_s_values(token).join('_')}"
       end
 
       private
 
-      def parameter_to_arg(symbol)
-        if (arg = @parameter_to_arg[symbol.s_value].dup)
-          arg.alias_name = symbol.alias_name
+      # @rbs (Array[Lexer::Token] params, Array[Lexer::Token] actual_args) -> Hash[String, Lexer::Token]
+      def map_params_to_args(params, actual_args)
+        params.zip(actual_args).map do |param, arg|
+          [param.s_value, arg]
+        end.to_h
+      end
+
+      # @rbs (Lexer::Token::InstantiateRule sym) -> Array[Lexer::Token]
+      def resolved_args(sym)
+        sym.args.map { |arg| resolve_symbol(arg) }
+      end
+
+      # @rbs (Lexer::Token sym) -> Lexer::Token
+      def param_to_arg(sym)
+        if (arg = @param_to_arg[sym.s_value].dup)
+          arg.alias_name = sym.alias_name
         end
-        arg
+        arg || sym
       end
 
+      # @rbs (Lexer::Token::InstantiateRule token) -> Array[String]
       def token_to_args_s_values(token)
         token.args.flat_map do |arg|
           resolved = resolve_symbol(arg)
diff --git a/lib/lrama/grammar/rule_builder.rb b/lib/lrama/grammar/rule_builder.rb
index d82da5f9..481a3780 100644
--- a/lib/lrama/grammar/rule_builder.rb
+++ b/lib/lrama/grammar/rule_builder.rb
@@ -73,7 +73,7 @@ def resolve_inline_rules
             inline_rule.rhs_list.each do |inline_rhs|
               rule_builder = RuleBuilder.new(@rule_counter, @midrule_action_counter, @parameterizing_rule_resolver, lhs_tag: lhs_tag)
               if token.is_a?(Lexer::Token::InstantiateRule)
-                resolve_inline_rhs(rule_builder, inline_rhs, i, Binding.new(inline_rule, token.args))
+                resolve_inline_rhs(rule_builder, inline_rhs, i, Binding.new(inline_rule.parameters, token.args))
               else
                 resolve_inline_rhs(rule_builder, inline_rhs, i)
               end
@@ -135,7 +135,7 @@ def process_rhs
             parameterizing_rule = @parameterizing_rule_resolver.find_rule(token)
             raise "Unexpected token. #{token}" unless parameterizing_rule
 
-            bindings = Binding.new(parameterizing_rule, token.args)
+            bindings = Binding.new(parameterizing_rule.parameters, token.args)
             lhs_s_value = bindings.concatenated_args_str(token)
             if (created_lhs = @parameterizing_rule_resolver.created_lhs(lhs_s_value))
               @replaced_rhs << created_lhs
diff --git a/sig/generated/lrama/grammar/binding.rbs b/sig/generated/lrama/grammar/binding.rbs
new file mode 100644
index 00000000..c6818a2e
--- /dev/null
+++ b/sig/generated/lrama/grammar/binding.rbs
@@ -0,0 +1,34 @@
+# Generated from lib/lrama/grammar/binding.rb with RBS::Inline
+
+module Lrama
+  class Grammar
+    class Binding
+      @actual_args: Array[Lexer::Token]
+
+      @param_to_arg: Hash[String, Lexer::Token]
+
+      # @rbs (Array[Lexer::Token] params, Array[Lexer::Token] actual_args) -> void
+      def initialize: (Array[Lexer::Token] params, Array[Lexer::Token] actual_args) -> void
+
+      # @rbs (Lexer::Token sym) -> Lexer::Token
+      def resolve_symbol: (Lexer::Token sym) -> Lexer::Token
+
+      # @rbs (Lexer::Token::InstantiateRule token) -> String
+      def concatenated_args_str: (Lexer::Token::InstantiateRule token) -> String
+
+      private
+
+      # @rbs (Array[Lexer::Token] params, Array[Lexer::Token] actual_args) -> Hash[String, Lexer::Token]
+      def map_params_to_args: (Array[Lexer::Token] params, Array[Lexer::Token] actual_args) -> Hash[String, Lexer::Token]
+
+      # @rbs (Lexer::Token::InstantiateRule sym) -> Array[Lexer::Token]
+      def resolved_args: (Lexer::Token::InstantiateRule sym) -> Array[Lexer::Token]
+
+      # @rbs (Lexer::Token sym) -> Lexer::Token
+      def param_to_arg: (Lexer::Token sym) -> Lexer::Token
+
+      # @rbs (Lexer::Token::InstantiateRule token) -> Array[String]
+      def token_to_args_s_values: (Lexer::Token::InstantiateRule token) -> Array[String]
+    end
+  end
+end
diff --git a/sig/lrama/grammar/binding.rbs b/sig/lrama/grammar/binding.rbs
deleted file mode 100644
index e8796455..00000000
--- a/sig/lrama/grammar/binding.rbs
+++ /dev/null
@@ -1,21 +0,0 @@
-module Lrama
-  class Grammar
-    class Binding
-      attr_reader actual_args: Array[Lexer::Token]
-      attr_reader count: Integer
-
-      @required_parameters_count: Integer
-      @parameters: Array[Lexer::Token]
-      @parameter_to_arg: untyped
-
-      def initialize: (Grammar::ParameterizingRule::Rule parameterizing_rule, Array[Lexer::Token] actual_args) -> void
-      def resolve_symbol: (Lexer::Token symbol) -> Lexer::Token
-      def concatenated_args_str: (Lexer::Token::InstantiateRule token) -> String
-
-      private
-
-      def parameter_to_arg: (Lexer::Token symbol) -> Lexer::Token?
-      def token_to_args_s_values: (Lexer::Token::InstantiateRule token) -> Array[String]
-    end
-  end
-end