diff --git a/src/ast/access_decoration.cc b/src/ast/access_decoration.cc
index ae0fdef6d6..3f7252a19a 100644
--- a/src/ast/access_decoration.cc
+++ b/src/ast/access_decoration.cc
@@ -20,10 +20,14 @@ namespace ast {
 constexpr const DecorationKind AccessDecoration::Kind;
 
 AccessDecoration::AccessDecoration(AccessControl val, const Source& source)
-    : TypeDecoration(Kind, source), value_(val) {}
+    : TypeDecoration(source), value_(val) {}
 
 AccessDecoration::~AccessDecoration() = default;
 
+DecorationKind AccessDecoration::GetKind() const {
+  return Kind;
+}
+
 bool AccessDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || TypeDecoration::IsKind(kind);
 }
diff --git a/src/ast/access_decoration.h b/src/ast/access_decoration.h
index 69a7244e28..3be11d55e5 100644
--- a/src/ast/access_decoration.h
+++ b/src/ast/access_decoration.h
@@ -35,6 +35,9 @@ class AccessDecoration : public TypeDecoration {
   explicit AccessDecoration(AccessControl value, const Source& source);
   ~AccessDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/array_decoration.cc b/src/ast/array_decoration.cc
index d7f22f3935..7832e9be8c 100644
--- a/src/ast/array_decoration.cc
+++ b/src/ast/array_decoration.cc
@@ -23,11 +23,14 @@ namespace ast {
 
 constexpr const DecorationKind ArrayDecoration::Kind;
 
-ArrayDecoration::ArrayDecoration(DecorationKind kind, const Source& source)
-    : Decoration(kind, source) {}
+ArrayDecoration::ArrayDecoration(const Source& source) : Decoration(source) {}
 
 ArrayDecoration::~ArrayDecoration() = default;
 
+DecorationKind ArrayDecoration::GetKind() const {
+  return Kind;
+}
+
 bool ArrayDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind;
 }
diff --git a/src/ast/array_decoration.h b/src/ast/array_decoration.h
index 77b616459c..f1a953bbaf 100644
--- a/src/ast/array_decoration.h
+++ b/src/ast/array_decoration.h
@@ -34,6 +34,9 @@ class ArrayDecoration : public Decoration {
 
   ~ArrayDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
@@ -47,9 +50,8 @@ class ArrayDecoration : public Decoration {
 
  protected:
   /// Constructor
-  /// @param kind the decoration kind
   /// @param source the source of this decoration
-  ArrayDecoration(DecorationKind kind, const Source& source);
+  explicit ArrayDecoration(const Source& source);
 };
 
 /// A list of array decorations
diff --git a/src/ast/binding_decoration.cc b/src/ast/binding_decoration.cc
index d0c5063886..2af35d903e 100644
--- a/src/ast/binding_decoration.cc
+++ b/src/ast/binding_decoration.cc
@@ -20,10 +20,14 @@ namespace ast {
 constexpr const DecorationKind BindingDecoration::Kind;
 
 BindingDecoration::BindingDecoration(uint32_t val, const Source& source)
-    : VariableDecoration(Kind, source), value_(val) {}
+    : VariableDecoration(source), value_(val) {}
 
 BindingDecoration::~BindingDecoration() = default;
 
+DecorationKind BindingDecoration::GetKind() const {
+  return Kind;
+}
+
 bool BindingDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || VariableDecoration::IsKind(kind);
 }
diff --git a/src/ast/binding_decoration.h b/src/ast/binding_decoration.h
index 4f65eabfd0..8e40626bc6 100644
--- a/src/ast/binding_decoration.h
+++ b/src/ast/binding_decoration.h
@@ -34,6 +34,9 @@ class BindingDecoration : public VariableDecoration {
   BindingDecoration(uint32_t value, const Source& source);
   ~BindingDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/builtin_decoration.cc b/src/ast/builtin_decoration.cc
index 7cb49c73f3..28108d3536 100644
--- a/src/ast/builtin_decoration.cc
+++ b/src/ast/builtin_decoration.cc
@@ -20,10 +20,14 @@ namespace ast {
 constexpr const DecorationKind BuiltinDecoration::Kind;
 
 BuiltinDecoration::BuiltinDecoration(Builtin builtin, const Source& source)
-    : VariableDecoration(Kind, source), builtin_(builtin) {}
+    : VariableDecoration(source), builtin_(builtin) {}
 
 BuiltinDecoration::~BuiltinDecoration() = default;
 
+DecorationKind BuiltinDecoration::GetKind() const {
+  return Kind;
+}
+
 bool BuiltinDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || VariableDecoration::IsKind(kind);
 }
diff --git a/src/ast/builtin_decoration.h b/src/ast/builtin_decoration.h
index 75d40a5c95..07dedfe029 100644
--- a/src/ast/builtin_decoration.h
+++ b/src/ast/builtin_decoration.h
@@ -33,6 +33,9 @@ class BuiltinDecoration : public VariableDecoration {
   BuiltinDecoration(Builtin builtin, const Source& source);
   ~BuiltinDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/constant_id_decoration.cc b/src/ast/constant_id_decoration.cc
index 145b80d572..3cd219da0f 100644
--- a/src/ast/constant_id_decoration.cc
+++ b/src/ast/constant_id_decoration.cc
@@ -20,10 +20,14 @@ namespace ast {
 constexpr const DecorationKind ConstantIdDecoration::Kind;
 
 ConstantIdDecoration::ConstantIdDecoration(uint32_t val, const Source& source)
-    : VariableDecoration(Kind, source), value_(val) {}
+    : VariableDecoration(source), value_(val) {}
 
 ConstantIdDecoration::~ConstantIdDecoration() = default;
 
+DecorationKind ConstantIdDecoration::GetKind() const {
+  return Kind;
+}
+
 bool ConstantIdDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || VariableDecoration::IsKind(kind);
 }
diff --git a/src/ast/constant_id_decoration.h b/src/ast/constant_id_decoration.h
index 3fb8ef8fb6..b2776fd33d 100644
--- a/src/ast/constant_id_decoration.h
+++ b/src/ast/constant_id_decoration.h
@@ -33,6 +33,9 @@ class ConstantIdDecoration : public VariableDecoration {
   ConstantIdDecoration(uint32_t val, const Source& source);
   ~ConstantIdDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/decoration.h b/src/ast/decoration.h
index 61c4cff8d2..c7dffdb449 100644
--- a/src/ast/decoration.h
+++ b/src/ast/decoration.h
@@ -51,6 +51,9 @@ class Decoration : public Node {
  public:
   ~Decoration() override;
 
+  /// @return the decoration kind
+  virtual DecorationKind GetKind() const = 0;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
@@ -62,21 +65,13 @@ class Decoration : public Node {
     return IsKind(TO::Kind);
   }
 
-  /// @return the decoration kind
-  DecorationKind GetKind() const { return kind_; }
-
   /// @returns true if the node is valid
   bool IsValid() const override;
 
  protected:
   /// Constructor
-  /// @param kind represents the derived type
   /// @param source the source of this decoration
-  Decoration(DecorationKind kind, const Source& source)
-      : Node(source), kind_(kind) {}
-
- private:
-  DecorationKind const kind_;
+  explicit Decoration(const Source& source) : Node(source) {}
 };
 
 /// As dynamically casts |deco| to the target type |TO|.
diff --git a/src/ast/function_decoration.cc b/src/ast/function_decoration.cc
index fc1409ab32..2d11714b21 100644
--- a/src/ast/function_decoration.cc
+++ b/src/ast/function_decoration.cc
@@ -24,12 +24,15 @@ namespace ast {
 
 constexpr const DecorationKind FunctionDecoration::Kind;
 
-FunctionDecoration::FunctionDecoration(DecorationKind kind,
-                                       const Source& source)
-    : Decoration(kind, source) {}
+FunctionDecoration::FunctionDecoration(const Source& source)
+    : Decoration(source) {}
 
 FunctionDecoration::~FunctionDecoration() = default;
 
+DecorationKind FunctionDecoration::GetKind() const {
+  return Kind;
+}
+
 bool FunctionDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind;
 }
diff --git a/src/ast/function_decoration.h b/src/ast/function_decoration.h
index 1d778faaf5..86b951420a 100644
--- a/src/ast/function_decoration.h
+++ b/src/ast/function_decoration.h
@@ -35,6 +35,9 @@ class FunctionDecoration : public Decoration {
 
   ~FunctionDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
@@ -52,9 +55,8 @@ class FunctionDecoration : public Decoration {
 
  protected:
   /// Constructor
-  /// @param kind the decoration kind
   /// @param source the source of this decoration
-  FunctionDecoration(DecorationKind kind, const Source& source);
+  explicit FunctionDecoration(const Source& source);
 };
 
 /// A list of function decorations
diff --git a/src/ast/location_decoration.cc b/src/ast/location_decoration.cc
index 0aa7f1aa54..51737d99ef 100644
--- a/src/ast/location_decoration.cc
+++ b/src/ast/location_decoration.cc
@@ -20,10 +20,14 @@ namespace ast {
 constexpr const DecorationKind LocationDecoration::Kind;
 
 LocationDecoration::LocationDecoration(uint32_t val, const Source& source)
-    : VariableDecoration(Kind, source), value_(val) {}
+    : VariableDecoration(source), value_(val) {}
 
 LocationDecoration::~LocationDecoration() = default;
 
+DecorationKind LocationDecoration::GetKind() const {
+  return Kind;
+}
+
 bool LocationDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || VariableDecoration::IsKind(kind);
 }
diff --git a/src/ast/location_decoration.h b/src/ast/location_decoration.h
index abbfefe0d3..ae7aed151b 100644
--- a/src/ast/location_decoration.h
+++ b/src/ast/location_decoration.h
@@ -34,6 +34,9 @@ class LocationDecoration : public VariableDecoration {
   explicit LocationDecoration(uint32_t value, const Source& source);
   ~LocationDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/set_decoration.cc b/src/ast/set_decoration.cc
index 9d1d502c8c..08d5312afc 100644
--- a/src/ast/set_decoration.cc
+++ b/src/ast/set_decoration.cc
@@ -18,7 +18,7 @@ namespace tint {
 namespace ast {
 
 SetDecoration::SetDecoration(uint32_t val, const Source& source)
-    : VariableDecoration(Kind, source), value_(val) {}
+    : VariableDecoration(source), value_(val) {}
 
 SetDecoration::~SetDecoration() = default;
 
diff --git a/src/ast/stage_decoration.cc b/src/ast/stage_decoration.cc
index d1f20a2ff4..ae996c8fef 100644
--- a/src/ast/stage_decoration.cc
+++ b/src/ast/stage_decoration.cc
@@ -20,10 +20,14 @@ namespace ast {
 constexpr const DecorationKind StageDecoration::Kind;
 
 StageDecoration::StageDecoration(ast::PipelineStage stage, const Source& source)
-    : FunctionDecoration(Kind, source), stage_(stage) {}
+    : FunctionDecoration(source), stage_(stage) {}
 
 StageDecoration::~StageDecoration() = default;
 
+DecorationKind StageDecoration::GetKind() const {
+  return Kind;
+}
+
 bool StageDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || FunctionDecoration::IsKind(kind);
 }
diff --git a/src/ast/stage_decoration.h b/src/ast/stage_decoration.h
index b7aa3b85fb..0b7e94a71b 100644
--- a/src/ast/stage_decoration.h
+++ b/src/ast/stage_decoration.h
@@ -33,6 +33,9 @@ class StageDecoration : public FunctionDecoration {
   StageDecoration(ast::PipelineStage stage, const Source& source);
   ~StageDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/stride_decoration.cc b/src/ast/stride_decoration.cc
index 58ac1a5245..d92bf58175 100644
--- a/src/ast/stride_decoration.cc
+++ b/src/ast/stride_decoration.cc
@@ -20,7 +20,11 @@ namespace ast {
 constexpr const DecorationKind StrideDecoration::Kind;
 
 StrideDecoration::StrideDecoration(uint32_t stride, const Source& source)
-    : ArrayDecoration(Kind, source), stride_(stride) {}
+    : ArrayDecoration(source), stride_(stride) {}
+
+DecorationKind StrideDecoration::GetKind() const {
+  return Kind;
+}
 
 bool StrideDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || ArrayDecoration::IsKind(kind);
diff --git a/src/ast/stride_decoration.h b/src/ast/stride_decoration.h
index 9b00563919..f97734ee49 100644
--- a/src/ast/stride_decoration.h
+++ b/src/ast/stride_decoration.h
@@ -36,6 +36,9 @@ class StrideDecoration : public ArrayDecoration {
   StrideDecoration(uint32_t stride, const Source& source);
   ~StrideDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/struct_block_decoration.cc b/src/ast/struct_block_decoration.cc
index b95299e3ae..585646d0c4 100644
--- a/src/ast/struct_block_decoration.cc
+++ b/src/ast/struct_block_decoration.cc
@@ -18,7 +18,7 @@ namespace tint {
 namespace ast {
 
 StructBlockDecoration::StructBlockDecoration(const Source& source)
-    : StructDecoration(Kind, source) {}
+    : StructDecoration(source) {}
 
 StructBlockDecoration::~StructBlockDecoration() = default;
 
diff --git a/src/ast/struct_decoration.cc b/src/ast/struct_decoration.cc
index 340ac1447f..5b93b909a3 100644
--- a/src/ast/struct_decoration.cc
+++ b/src/ast/struct_decoration.cc
@@ -19,11 +19,14 @@ namespace ast {
 
 constexpr const DecorationKind StructDecoration::Kind;
 
-StructDecoration::StructDecoration(DecorationKind kind, const Source& source)
-    : Decoration(kind, source) {}
+StructDecoration::StructDecoration(const Source& source) : Decoration(source) {}
 
 StructDecoration::~StructDecoration() = default;
 
+DecorationKind StructDecoration::GetKind() const {
+  return Kind;
+}
+
 bool StructDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind;
 }
diff --git a/src/ast/struct_decoration.h b/src/ast/struct_decoration.h
index 26b1901106..727ba7da84 100644
--- a/src/ast/struct_decoration.h
+++ b/src/ast/struct_decoration.h
@@ -32,6 +32,9 @@ class StructDecoration : public Decoration {
 
   ~StructDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
@@ -42,9 +45,8 @@ class StructDecoration : public Decoration {
 
  protected:
   /// Constructor
-  /// @param kind the decoration kind
   /// @param source the source of this decoration
-  explicit StructDecoration(DecorationKind kind, const Source& source);
+  explicit StructDecoration(const Source& source);
 };
 
 /// List of struct decorations
diff --git a/src/ast/struct_member_decoration.cc b/src/ast/struct_member_decoration.cc
index efbae62db9..8573bc727e 100644
--- a/src/ast/struct_member_decoration.cc
+++ b/src/ast/struct_member_decoration.cc
@@ -23,12 +23,15 @@ namespace ast {
 
 constexpr const DecorationKind StructMemberDecoration::Kind;
 
-StructMemberDecoration::StructMemberDecoration(DecorationKind kind,
-                                               const Source& source)
-    : Decoration(kind, source) {}
+StructMemberDecoration::StructMemberDecoration(const Source& source)
+    : Decoration(source) {}
 
 StructMemberDecoration::~StructMemberDecoration() = default;
 
+DecorationKind StructMemberDecoration::GetKind() const {
+  return Kind;
+}
+
 bool StructMemberDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind;
 }
diff --git a/src/ast/struct_member_decoration.h b/src/ast/struct_member_decoration.h
index 188c77751f..1652df3341 100644
--- a/src/ast/struct_member_decoration.h
+++ b/src/ast/struct_member_decoration.h
@@ -34,6 +34,9 @@ class StructMemberDecoration : public Decoration {
 
   ~StructMemberDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
@@ -47,9 +50,8 @@ class StructMemberDecoration : public Decoration {
 
  protected:
   /// Constructor
-  /// @param kind the decoration kind
   /// @param source the source of this decoration
-  explicit StructMemberDecoration(DecorationKind kind, const Source& source);
+  explicit StructMemberDecoration(const Source& source);
 };
 
 /// A list of struct member decorations
diff --git a/src/ast/struct_member_offset_decoration.cc b/src/ast/struct_member_offset_decoration.cc
index b2ad2b494f..c211c5bb2c 100644
--- a/src/ast/struct_member_offset_decoration.cc
+++ b/src/ast/struct_member_offset_decoration.cc
@@ -21,7 +21,11 @@ constexpr const DecorationKind StructMemberOffsetDecoration::Kind;
 
 StructMemberOffsetDecoration::StructMemberOffsetDecoration(uint32_t offset,
                                                            const Source& source)
-    : StructMemberDecoration(Kind, source), offset_(offset) {}
+    : StructMemberDecoration(source), offset_(offset) {}
+
+DecorationKind StructMemberOffsetDecoration::GetKind() const {
+  return Kind;
+}
 
 bool StructMemberOffsetDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || StructMemberDecoration::IsKind(kind);
diff --git a/src/ast/struct_member_offset_decoration.h b/src/ast/struct_member_offset_decoration.h
index 6e5a5a690d..60a206851b 100644
--- a/src/ast/struct_member_offset_decoration.h
+++ b/src/ast/struct_member_offset_decoration.h
@@ -37,6 +37,9 @@ class StructMemberOffsetDecoration : public StructMemberDecoration {
   StructMemberOffsetDecoration(uint32_t offset, const Source& source);
   ~StructMemberOffsetDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
diff --git a/src/ast/type_decoration.cc b/src/ast/type_decoration.cc
index 3f13343bbf..763d24cfcc 100644
--- a/src/ast/type_decoration.cc
+++ b/src/ast/type_decoration.cc
@@ -23,11 +23,14 @@ namespace ast {
 
 constexpr const DecorationKind TypeDecoration::Kind;
 
-TypeDecoration::TypeDecoration(DecorationKind kind, const Source& source)
-    : Decoration(kind, source) {}
+TypeDecoration::TypeDecoration(const Source& source) : Decoration(source) {}
 
 TypeDecoration::~TypeDecoration() = default;
 
+DecorationKind TypeDecoration::GetKind() const {
+  return Kind;
+}
+
 bool TypeDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind;
 }
diff --git a/src/ast/type_decoration.h b/src/ast/type_decoration.h
index f457e39706..f515a4b663 100644
--- a/src/ast/type_decoration.h
+++ b/src/ast/type_decoration.h
@@ -35,6 +35,9 @@ class TypeDecoration : public Decoration {
 
   ~TypeDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
@@ -48,9 +51,8 @@ class TypeDecoration : public Decoration {
 
  protected:
   /// Constructor
-  /// @param kind the decoration kind
   /// @param source the source of this decoration
-  explicit TypeDecoration(DecorationKind kind, const Source& source);
+  explicit TypeDecoration(const Source& source);
 };
 
 /// A list of type decorations
diff --git a/src/ast/variable_decoration.cc b/src/ast/variable_decoration.cc
index e37d5bde46..9b7d2c0a71 100644
--- a/src/ast/variable_decoration.cc
+++ b/src/ast/variable_decoration.cc
@@ -27,12 +27,15 @@ namespace ast {
 
 constexpr const DecorationKind VariableDecoration::Kind;
 
-VariableDecoration::VariableDecoration(DecorationKind kind,
-                                       const Source& source)
-    : Decoration(kind, source) {}
+VariableDecoration::VariableDecoration(const Source& source)
+    : Decoration(source) {}
 
 VariableDecoration::~VariableDecoration() = default;
 
+DecorationKind VariableDecoration::GetKind() const {
+  return Kind;
+}
+
 bool VariableDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind;
 }
diff --git a/src/ast/variable_decoration.h b/src/ast/variable_decoration.h
index 6c44242903..e5c18fd782 100644
--- a/src/ast/variable_decoration.h
+++ b/src/ast/variable_decoration.h
@@ -39,6 +39,9 @@ class VariableDecoration : public Decoration {
 
   ~VariableDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.
@@ -68,9 +71,8 @@ class VariableDecoration : public Decoration {
 
  protected:
   /// Constructor
-  /// @param kind the decoration kind
   /// @param source the source of this decoration
-  VariableDecoration(DecorationKind kind, const Source& source);
+  explicit VariableDecoration(const Source& source);
 };
 
 /// A list of variable decorations
diff --git a/src/ast/workgroup_decoration.cc b/src/ast/workgroup_decoration.cc
index e9ecab6ccf..1c4c58b704 100644
--- a/src/ast/workgroup_decoration.cc
+++ b/src/ast/workgroup_decoration.cc
@@ -20,21 +20,25 @@ namespace ast {
 constexpr const DecorationKind WorkgroupDecoration::Kind;
 
 WorkgroupDecoration::WorkgroupDecoration(uint32_t x, const Source& source)
-    : FunctionDecoration(Kind, source), x_(x) {}
+    : FunctionDecoration(source), x_(x) {}
 
 WorkgroupDecoration::WorkgroupDecoration(uint32_t x,
                                          uint32_t y,
                                          const Source& source)
-    : FunctionDecoration(Kind, source), x_(x), y_(y) {}
+    : FunctionDecoration(source), x_(x), y_(y) {}
 
 WorkgroupDecoration::WorkgroupDecoration(uint32_t x,
                                          uint32_t y,
                                          uint32_t z,
                                          const Source& source)
-    : FunctionDecoration(Kind, source), x_(x), y_(y), z_(z) {}
+    : FunctionDecoration(source), x_(x), y_(y), z_(z) {}
 
 WorkgroupDecoration::~WorkgroupDecoration() = default;
 
+DecorationKind WorkgroupDecoration::GetKind() const {
+  return Kind;
+}
+
 bool WorkgroupDecoration::IsKind(DecorationKind kind) const {
   return kind == Kind || FunctionDecoration::IsKind(kind);
 }
diff --git a/src/ast/workgroup_decoration.h b/src/ast/workgroup_decoration.h
index cbfb5aafcb..fbdbf06e5c 100644
--- a/src/ast/workgroup_decoration.h
+++ b/src/ast/workgroup_decoration.h
@@ -47,6 +47,9 @@ class WorkgroupDecoration : public FunctionDecoration {
   WorkgroupDecoration(uint32_t x, uint32_t y, uint32_t z, const Source& source);
   ~WorkgroupDecoration() override;
 
+  /// @return the decoration kind
+  DecorationKind GetKind() const override;
+
   /// @param kind the decoration kind
   /// @return true if this Decoration is of the (or derives from) the given
   /// kind.