docs: Update documentation and Doxygen documentation generation
diff --git a/ndn.cxx/detail/error.h b/ndn.cxx/detail/error.h
index a1f1e34..db6b751 100644
--- a/ndn.cxx/detail/error.h
+++ b/ndn.cxx/detail/error.h
@@ -35,6 +35,10 @@
 
 NDN_NAMESPACE_BEGIN
 
+/**
+ * @ingroup ndn-cxx
+ * @brief Namespace holding all errors from NDN.cxx API
+ */
 namespace error
 {