diff --git a/src/cst/tags.rs b/src/cst/tags.rs
index 5e43233..f0400af 100644
--- a/src/cst/tags.rs
+++ b/src/cst/tags.rs
@@ -43,6 +43,8 @@ impl Tag {
     pub const PARAM_DECLARATION: &'static str = "kParamDeclaration";
     pub const PARAM_TYPE: &'static str = "kParamType";
     pub const TRAILING_ASSIGN: &'static str = "kTrailingAssign";
+    pub const FORMAL_PARAMETER_DECLARATION: &'static str = "kFormalParameterListDeclaration";
+    pub const FORMAL_PARAMETER: &'static str = "kFormalParameterList";
 
     pub const DATA_TYPE_IMPLICIT_ID_DIMENSIONS: &'static str = "kDataTypeImplicitIdDimensions";
     pub const DATA_TYPE: &'static str = "kDataType";