If there is no interface associated with item directly (external checks, calculated items, etc.) and for some reason there is no interface for host (usually this should not happen, in my case host was created by means of data.tmpl surgery) server will fail to resolve {ITEM.NAME} macro even though there are no positional macros ($1, $2, etc.) and no {HOST.IP/DNS/CONN} macros and debug logs won't be specific about the reason why.