Server builder plugin
diff --git a/tools/doxygen/Doxyfile.c++.internal b/tools/doxygen/Doxyfile.c++.internal
index 312fd17..56f51f6 100644
--- a/tools/doxygen/Doxyfile.c++.internal
+++ b/tools/doxygen/Doxyfile.c++.internal
@@ -777,6 +777,8 @@
 include/grpc++/impl/rpc_service_method.h \
 include/grpc++/impl/serialization_traits.h \
 include/grpc++/impl/server_builder_option.h \
+include/grpc++/impl/server_builder_plugin.h \
+include/grpc++/impl/server_initializer.h \
 include/grpc++/impl/service_type.h \
 include/grpc++/impl/sync.h \
 include/grpc++/impl/sync_cxx11.h \