diff --git a/plugins/commands/serve/mappers/basis.rb b/plugins/commands/serve/mappers/basis.rb
index 7979a573f..2f6a838ee 100644
--- a/plugins/commands/serve/mappers/basis.rb
+++ b/plugins/commands/serve/mappers/basis.rb
@@ -39,21 +39,6 @@ module VagrantPlugins
           project
         end
       end
-
-      # Build a synced folder client from a serialized proto string
-      class BasisFromString < Mapper
-        def initialize
-          inputs = [].tap do |i|
-            i << Input.new(type: String)
-            i << Input.new(type: Broker)
-          end
-          super(inputs: inputs, output: Client::Basis, func: method(:converter))
-        end
-
-        def converter(proto, broker)
-          Client::Basis.load(proto, broker: broker)
-        end
-      end
     end
   end
 end
diff --git a/plugins/commands/serve/mappers/machine.rb b/plugins/commands/serve/mappers/machine.rb
index 023a202e3..bff06f5c2 100644
--- a/plugins/commands/serve/mappers/machine.rb
+++ b/plugins/commands/serve/mappers/machine.rb
@@ -53,21 +53,6 @@ module VagrantPlugins
         end
       end
 
-      # Build a machine client from a serialized proto string
-      class MachineFromString < Mapper
-        def initialize
-          inputs = [].tap do |i|
-            i << Input.new(type: String)
-            i << Input.new(type: Broker)
-          end
-          super(inputs: inputs, output: Client::Target::Machine, func: method(:converter))
-        end
-
-        def converter(proto, broker)
-          Client::Target::Machine.load(proto, broker: broker)
-        end
-      end
-
       # Build a machine from a target
       class MachineFromTarget < Mapper
         def initialize
diff --git a/plugins/commands/serve/mappers/project.rb b/plugins/commands/serve/mappers/project.rb
index 4ffad3c01..00313f9d9 100644
--- a/plugins/commands/serve/mappers/project.rb
+++ b/plugins/commands/serve/mappers/project.rb
@@ -58,21 +58,6 @@ module VagrantPlugins
         end
       end
 
-      # Build a machine client from a serialized proto string
-      class ProjectFromString < Mapper
-        def initialize
-          inputs = [].tap do |i|
-            i << Input.new(type: String)
-            i << Input.new(type: Broker)
-          end
-          super(inputs: inputs, output: Client::Project, func: method(:converter))
-        end
-
-        def converter(proto, broker)
-          Client::Project.load(proto, broker: broker)
-        end
-      end
-
       class ProjectFromTarget < Mapper
         def initialize
           inputs = [].tap do |i|
diff --git a/plugins/commands/serve/mappers/synced_folder.rb b/plugins/commands/serve/mappers/synced_folder.rb
index 4959bab30..8b42dd325 100644
--- a/plugins/commands/serve/mappers/synced_folder.rb
+++ b/plugins/commands/serve/mappers/synced_folder.rb
@@ -50,21 +50,6 @@ module VagrantPlugins
         end
       end
 
-      # Build a synced folder client from a serialized proto string
-      class SyncedFolderFromString < Mapper
-        def initialize
-          inputs = [].tap do |i|
-            i << Input.new(type: String)
-            i << Input.new(type: Broker)
-          end
-          super(inputs: inputs, output: Client::SyncedFolder, func: method(:converter))
-        end
-
-        def converter(proto, broker)
-          Client::SyncedFolder.load(proto, broker: broker)
-        end
-      end
-
       # Build a synced folder from a synced folder client
       class SyncedFolderFromProto < Mapper
         def initialize
diff --git a/plugins/commands/serve/mappers/target_index.rb b/plugins/commands/serve/mappers/target_index.rb
index 9083f9210..c3400d28c 100644
--- a/plugins/commands/serve/mappers/target_index.rb
+++ b/plugins/commands/serve/mappers/target_index.rb
@@ -52,21 +52,6 @@ module VagrantPlugins
           Client::TargetIndex.load(proto, broker: broker)
         end
       end
-
-      # Build a target index client from a serialized proto string
-      class TargetIndexFromString < Mapper
-        def initialize
-          inputs = [].tap do |i|
-            i << Input.new(type: String)
-            i << Input.new(type: Broker)
-          end
-          super(inputs: inputs, output: Client::TargetIndex, func: method(:converter))
-        end
-
-        def converter(proto, broker)
-          Client::TargetIndex.load(proto, broker: broker)
-        end
-      end
     end
   end
 end
diff --git a/plugins/commands/serve/mappers/terminal.rb b/plugins/commands/serve/mappers/terminal.rb
index a6a06ebb3..15793864c 100644
--- a/plugins/commands/serve/mappers/terminal.rb
+++ b/plugins/commands/serve/mappers/terminal.rb
@@ -53,21 +53,6 @@ module VagrantPlugins
         end
       end
 
-      # Build a terminal client from a serialized proto string
-      class TerminalFromString < Mapper
-        def initialize
-          inputs = [].tap do |i|
-            i << Input.new(type: String)
-            i << Input.new(type: Broker)
-          end
-          super(inputs: inputs, output: Client::Terminal, func: method(:converter))
-        end
-
-        def converter(proto, broker)
-          Client::Terminal.load(proto, broker: broker)
-        end
-      end
-
       class TerminalFromProject < Mapper
         def initialize
           super(