https://musicbrainz.org/doc/Release_Group/Type lists 12 secondary types.

https://musicbrainz.org/doc/MusicBrainz_API#Release_.28Group.29_Type_and_Status lists 11 secondary types

• lists "broadcast" as secondary instead of primary
• no mention of "Demo" or "Field recording"

It's also not explicitly stated whether these values are just lower case versions of the english names for the types, or whether they are case sensitive. Looking at the code, they are strictly lower case, except that "sa-" and "va-" are also accepted as prefix, with no documentation that I can find (and no obvious effect on results).

Note: For API purposes, it would be nice if values with blanks or / could be avoided; perhaps by adding "audio-drama", "mixtape"/"street"/"mixtape-street" and "field-recording" as aliases for "audio drama", "mixtape/street" and "field recording".

https://github.com/metabrainz/musicbrainz-server/blob/2fa2c52710774fdeda2f5b9002bf6e7d00b85e0d/t/sql/initial.sql#L921 lists only 10 secondary types, lacking "Audio drama", "Demo" and "Field recording"

Is this not the canonical set?

Same issue with release status.

https://musicbrainz.org/doc/Release#Status lists 6 possible values.
https://github.com/metabrainz/musicbrainz-server/blob/2fa2c52710774fdeda2f5b9002bf6e7d00b85e0d/t/sql/initial.sql#L939 does too.

https://musicbrainz.org/doc/MusicBrainz_API#Release_.28Group.29_Type_and_Status only lists 4 - no "withdrawn" or "cancelled".