diff --git a/source/MaterialXGenShader/HwShaderGenerator.h b/source/MaterialXGenShader/HwShaderGenerator.h
index 3712410606..d78aaf917a 100644
--- a/source/MaterialXGenShader/HwShaderGenerator.h
+++ b/source/MaterialXGenShader/HwShaderGenerator.h
@@ -343,7 +343,7 @@ class MX_GENSHADER_API HwShaderGenerator : public ShaderGenerator
     mutable ClosureContext _defEmission;
 };
 
-/// @class HwShaderGenerator
+/// @class HwImplementation
 /// Base class for HW node implementations.
 class MX_GENSHADER_API HwImplementation : public ShaderNodeImpl
 {
diff --git a/source/MaterialXGenShader/Nodes/HwTransformNode.h b/source/MaterialXGenShader/Nodes/HwTransformNode.h
index a97e57405c..2103f3b4c8 100644
--- a/source/MaterialXGenShader/Nodes/HwTransformNode.h
+++ b/source/MaterialXGenShader/Nodes/HwTransformNode.h
@@ -34,6 +34,7 @@ class MX_GENSHADER_API HwTransformNode : public ShaderNodeImpl
     static const string WORLD;
 };
 
+/// Vector transform implementation for hardware languages
 class MX_GENSHADER_API HwTransformVectorNode : public HwTransformNode
 {
   public:
@@ -45,6 +46,7 @@ class MX_GENSHADER_API HwTransformVectorNode : public HwTransformNode
     string getHomogeneousCoordinate() const override { return "0.0"; }
 };
 
+/// Point transform implementation for hardware languages
 class MX_GENSHADER_API HwTransformPointNode : public HwTransformVectorNode
 {
   public:
@@ -54,6 +56,7 @@ class MX_GENSHADER_API HwTransformPointNode : public HwTransformVectorNode
     string getHomogeneousCoordinate() const override { return "1.0"; }
 };
 
+/// Normal transform implementation for hardware languages
 class MX_GENSHADER_API HwTransformNormalNode : public HwTransformNode
 {
   public:
diff --git a/source/MaterialXGenShader/TypeDesc.h b/source/MaterialXGenShader/TypeDesc.h
index d19fea604a..b61c598caf 100644
--- a/source/MaterialXGenShader/TypeDesc.h
+++ b/source/MaterialXGenShader/TypeDesc.h
@@ -275,6 +275,8 @@ class MX_GENSHADER_API StructTypeDesc
     vector<StructMemberTypeDesc> _members;
 };
 
+/// @class StructTypeDescRegistry
+/// Helper class for struct type registration.
 class MX_GENSHADER_API StructTypeDescRegistry
 {
   public: