complex types and arrays can be passed by value to functions as JSON, however the structure of the JSON may contain characters (urls, types prefixed with "#", etc.) which are not valid in the path of the URL. Thus, complex types/arrays may only be passed by value as parameters using a parameter alias (whose value is passed as a query option).

This is supported from the ABNF, but it takes some digging to figure out. It would be good to call this out in the prose.