diff --git a/plugins/commands/serve/client/capability_platform.rb b/plugins/commands/serve/client/capability_platform.rb
index 27b374821..788efeb7e 100644
--- a/plugins/commands/serve/client/capability_platform.rb
+++ b/plugins/commands/serve/client/capability_platform.rb
@@ -8,7 +8,7 @@ module VagrantPlugins
         #
         # @return [SDK::FuncSpec, Proc]
         def has_capability_func
-          spec = client.has_capability_spec
+          spec = client.has_capability_spec(Empty.new)
           cb = proc do |args|
             client.has_capability(args).has_capability
           end
@@ -52,8 +52,9 @@ module VagrantPlugins
         def capability(cap_name, *args)
           logger.debug("executing capability #{cap_name}")
           spec, cb = capability_func(cap_name)
-          args << Type::Direct.new(value: args)
-          cb.call(cap_name, generate_funcspec_args(spec, *args))
+          cb.call(cap_name,
+            generate_funcspec_args(spec,
+              Type::Direct.new(value: args), *args))
         end
       end
     end
diff --git a/plugins/commands/serve/client/host.rb b/plugins/commands/serve/client/host.rb
index 55a871309..20bb0e83f 100644
--- a/plugins/commands/serve/client/host.rb
+++ b/plugins/commands/serve/client/host.rb
@@ -7,7 +7,7 @@ module VagrantPlugins
         #
         # @return [SDK::FuncSpec, Proc]
         def parent_func
-          spec = client.parent_spec
+          spec = client.parent_spec(Empty.new)
           cb = proc do |args|
             client.parent(args).parent
           end
diff --git a/plugins/commands/serve/client/push.rb b/plugins/commands/serve/client/push.rb
index e72248fe4..e20c77fe2 100644
--- a/plugins/commands/serve/client/push.rb
+++ b/plugins/commands/serve/client/push.rb
@@ -6,7 +6,7 @@ module VagrantPlugins
         #
         # @return [SDK::FuncSpec, Proc]
         def push_func
-          spec = client.push_spec
+          spec = client.push_spec(Empty.new)
           cb = proc do |args|
             client.push(args)
           end
diff --git a/plugins/commands/serve/client/synced_folder.rb b/plugins/commands/serve/client/synced_folder.rb
index 206de79ff..c0ba328fd 100644
--- a/plugins/commands/serve/client/synced_folder.rb
+++ b/plugins/commands/serve/client/synced_folder.rb
@@ -7,7 +7,7 @@ module VagrantPlugins
         #
         # @return [SDK::FuncSpec, Proc]
         def usable_func
-          spec = client.usable_spec
+          spec = client.usable_spec(Empty.new)
           cb = proc do |args|
             client.usable(args).usable
           end
@@ -26,7 +26,7 @@ module VagrantPlugins
         #
         # @return [SDK::FuncSpec, Proc]
         def enable_func
-          spec = client.enable_spec
+          spec = client.enable_spec(Empty.new)
           cb = proc do |args|
             client.enable(args)
           end
@@ -42,8 +42,11 @@ module VagrantPlugins
           run_func(machine, folders, opts)
         end
 
+        # Generate callback and spec for required arguments
+        #
+        # @return [SDK::FuncSpec, Proc]
         def disable_func
-          spec = client.disable_spec
+          spec = client.disable_spec(Empty.new)
           cb = proc do |args|
             client.disable(args)
           end
@@ -63,7 +66,7 @@ module VagrantPlugins
         #
         # @return [SDK::FuncSpec, Proc]
         def cleanup_func
-          spec = client.cleanup_spec
+          spec = client.cleanup_spec(Empty.new)
           cb = proc do |args|
             client.cleanup(args)
           end