diff --git a/theatre/core/src/propTypes/internals.ts b/theatre/core/src/propTypes/internals.ts
index 61f062f..1c5c674 100644
--- a/theatre/core/src/propTypes/internals.ts
+++ b/theatre/core/src/propTypes/internals.ts
@@ -17,8 +17,16 @@ export type IValidCompoundProps = {
   [K in string]: PropTypeConfig
 }
 
-// Question: Why doesn't this include Rgba? Should it include Marker?
-//  - Is this just for compound props?
+/**
+ *
+ * This does not include Rgba since Rgba does not have a predictable
+ * object shape. We prefer to infer that compound props are described as
+ * `Record<string, IShorthandProp>` for now.
+ *
+ * In the future, it might be reasonable to wrap these types up into something
+ * which would allow us to differentiate between values at runtime
+ * (e.g. `val.type = "Rgba"` vs `val.type = "Compound"` etc)
+ */
 type IShorthandProp =
   | string
   | number