"xid id" works on ur:xid but not ur:envelope

[shannona]

The "envelope xid id" command works fine on a ur:xid:

% envelope xid id ur:xid/tpsplftpsotanshdhdcxrydycfsnctbalkytftbazmvwguwzdwdmspwzdlhtdyfhrptnkgretkktfymufgutoyaylstpsotansgylftanshfhdcxtegttivdqdmnesqdaackjydsahielarefejpgmesfgftdifzidhefhwsbaialgwftansgrhdcxhkgmfsbwvdclbypmmnihbbttaobzktsbftrhcmsrcmaagrrtkelbiebaeclyldiooycscstpsojzgtkkgaieihjtjyiniyinihjpoycsfncsfgndhljpfd

ur:xid/hdcxrydycfsnctbalkytftbazmvwguwzdwdmspwzdlhtdyfhrptnkgretkktfymufgutcfimlnet

It does not work after assertions have been added to the XID:

% envelope xid id ur:envelope/lotpsotanshdhdcxtovdgednnnieltpsbgmnleihgygojkrekkfmmuwdutksspjswtbwsepsieftldvyoytpsojlihksjoihjpinihjtiaihgsihkoihjztpsokscxetcxkkihhsjpjkcxjojpjliyihjkjkinjljthsjzcxieihkoihjzjljojnihjtjyoytpsoimiajljpihgujeinjzjzjktpsoksfhfxjpkkjojyjliojphsjoisiniacxjojpjljyjliajljzjkdwcxieinjkjyjpinidkpjyihiecxiajljtjkihjtjkkpjkdwcxjnjlidinjzihcxjkihiakpjpinjykkoytpsojpihkoinieihjtiaihfxjljnjninjyjnihjtjytpsotansfphdcxrtttbnuthtpkbbasurwnjlimverkeocersceaagwidcefegtolylaewntbnnlgzsoytpsoiyiejljnhsinjttpsoksckfyinjkjyjpinidkpjyihiecxgukkjkjyihjnjkcxdscxguihiakpjpinjykkoyaylstpsotansgylftanshfhdcxbzbdjkdmzocwlpmdctnybdsftlbksbghvdmwlkwtjsrsmnehrhcaclssrnvantlktansgrhdcxdlhgynutlpbddezofzcapapldruoguwdrdtegmzejzihsgpremclcaeochbkgyhpoycscstpsoisfwgmhsiekojliaetoycsfncsfgoytpsoiojokpjpjojljkihtpsoksglfxjljtjyjpinidkpjyinjtiocxjyjlcxjojpinkohsiakkdpjojpihjkihjpkoinjtiocxjkkkjkjyihjnjkcxjyishsjycxjojpjljyihiajycxkokpjzjtihjphsidjzihcxjojljokpjzhsjyinjljtjkoytpsoiykohsjzkpihjktpsoksemgdjpinkohsiakkcxhsjkcxhscxiskpjnhsjtcxjpinioisjydwcxkpjkihjpcxhsioihjtiakkdwcxihjyisiniahsjzcxiehsjyhscxkpjkihpspfsrhe

Error: the envelope's subject is not a known value

The help file says it should:

% envelope xid id --help
Validate the XID document and return its XID identifier

Usage: envelope xid id [OPTIONS] [ENVELOPE]

And more generally, we probably want it to for consistency.