Merge pull request #796 from MicrosoftDocs/repo_sync_working_branch

Confirm merge from repo_sync_working_branch to main to sync with https://github.com/MicrosoftDocs/query-docs (branch main)

Author: DougKlopfenstein

query-languages/m/type-is.md

@@ -13,7 +13,9 @@ Type.Is(<b>type1</b> as type, <b>type2</b> as type) as logical
 
 ## About
 
-Determines if a value of `type1` is always compatible with `type2`.
+Determines if a value of `type1` is always compatible with `type2`. 
+
+Parameter `type2` should be a primitive (or nullable primitive) type value. Otherwise, this function's behavior is undefined and shouldn't be relied on.
 
 ## Example 1