diff --git a/design/pdl-language.md b/design/pdl-language.md
index 27195bd..ba77e4a 100644
--- a/design/pdl-language.md
+++ b/design/pdl-language.md
@@ -30,6 +30,7 @@ PDL allows defining a protocol using HOPP and TAPE.
 | []\<TYPE\> | OTA     |  * | Array of any type[^1]
 | Table      | KTV     |  * | Table with undefined schema
 | {...}      | KTV     |  * | Table with defined schema
+| Any        | *       |  * | Value of an undefined type
 
 [^1]: Excluding SI and SBA. I5 and U5 cannot be used in an array, but String and
 Buffer are simply forced to use their "long" variant.