Explain how maxLength applies to raw binary

Co-authored-by: Ralf Handl <[email protected]>

Author: handrews

versions/3.0.4.md

@@ -171,7 +171,7 @@ Two formats, `binary` and `byte`, describe different ways to work with binary da
 * `binary` is used where unencoded binary data is allowed, such as when sending a binary payload as an HTTP message body, or as part of a `multipart/*` payload that allows binary parts
 * `byte` is used where binary data is embedded in a text-only format such as `application/json` or `application/x-www-form-urlencoded`
 
-The `maxLength` keyword can be used to set an upper bound on the length of a binary payload; otherwise, a binary payload SHOULD be interpreted as a stream of indeterminate length.
+The `maxLength` keyword can be used to set an upper bound on the length (in octets) of a binary payload; otherwise, a binary payload SHOULD be interpreted as a stream of indeterminate length.
 
 Note that the encoding indicated by `byte`, which inflates the size of data in order to represent it as 7-bit ASCII text, is unrelated to HTTP's `Content-Encoding` header, which indicates whether and how a message body has been compressed.