Hey,
I’m skimming over the works of Chopin and there are many, for which some new types would come in handy.
For example: Mazurka, Waltz, Prelude, Fantasie, Polonaise, …
I don’t want to fight that all of these should be selectable as work type, but rather want to know how something qualifies as type. What do you think? 
The answer for most of them is “because they were proposed before we added the option to have work types”. Adding new work types is relatively simple nowadays, so we could always add more, but I think it would be good to know what a work type is before we do that 
Some people have proposed moving them to some sort of tagging mechanism where you can have multiple ones, and that sounds relatively reasonable to me in the long run (but isn’t trivial).
It is trivial to move work types to allowed values of a new work attribute in MBDB. The non-trivial part is to define/contextualize this new work attribute consistently/properly and to adapt both MB website display and Picard tagger to make use of it at least as efficiently as current work types.
I was thinking tag more than attribute because it seems a bit more genre-ish in that it’s a bit subjective/open, but I guess it’s not worse than the Ottoman stuff we already have in that regard.
Where are we now with work-types? The list of allowable types is really rather quirky - Aria to Zarzuela, passing by Quartet and Sonata along the way, but no (for example) Piano Trio, Chamber Music or Nocturne.
What is needed to add new items? I note that:
If it’s relatively simple, then how? If there is a resistance to doing so because “we don’t really know what a work type is”, then it doesn’t seem like anyone cares too much about that (unless there is a development I have missed).
A style ticket like any other.
Keep in mind “chamber music” isn’t really a work type IMO - that’s like saying “orchestral music” or “solo piano music” is a type (you could argue “Quartet” is the same, but not every work written for a quartet is a Quartet)
So, with STYLE-470: Add an instrument-work relationship for instrumentation in mind: duet—nonet ticketed (STYLE-940: Add Work types duet—[quartet]—nonet, with ‘terzet‘ rather than ’trio’). ‘Solo’ would be wished for, but that term misunderstood, and ‘unet’ even more so.
One must also consider the vocals exclusive sense (f.i. Schubert 2—4, Rigoletto quartet).
Is there a style guideline that says what a work type is?
Why? The normal English term is trio. If used at all, terzet only refers to a vocal composition.
There isn’t, to be fair (the section on work type on the Work docs is a wonderful circular definition) - but still, “chamber music” doesn’t match anything else we have on that list, it’s a different level of abstraction.
There is a useful list here https://www.collinsdictionary.com/word-lists/music-types-of-composition. It is similar to the list in my copy of “The Oxford companion to music”. How about a style ticket based on this?
If we are going to add a lot more work types (which I am for), could someone make the drop-down searchable?
I’m inclined to agree. I would call it a genre (here be dragons). I’m working on a new version of Classical Extras that will provide genres and sub-genres; I’m wondering if work-type fits into the sub-genre category.
That would be MBS-4102 and I’d love to see it happen for exactly the reason you give 
Agreed, but when will that happen, given that the ticket was 2012? Could we have a better list of work-types without waiting for that?
For conformity as a means to usability, ‘trio’ being also another type frequent enough for confusion even without delving onto languages other than English. (Note to others uninitiated: In ‘Composition for 3 voices’, that last word is not to be understood as necessarily vocal ones.) I understand your objection, and pointed to the exception as a precaution. Would anyone rather have ‘terzet’, then I will (or anyone can, me not yet familiar with JIRA) change it in the ticket. Sadly, plain numbers probably cannot cut this deal.
I’m in favour of adopting a definition like that offered by the Music Library Association:
A “type of composition” is defined in the RDA Glossary as a “form, a genre, or a generic term used frequently by different composers (e.g., capriccio, concerto, intermezzo, Magnificat, mass, movement, muziek, nocturne, requiem, Stück, symphony, suite, Te Deum, trio sonata).”
That looks excellent. However, the full list looks far too long to use without something like MBS-4102. Perhaps someone could propose a sub-list that would be workable in the current technology?
BTW @Griomo, note that the Cataloging and Metadata Committee of the MLA say “Terzett (German); use trio.”
I also note German spelling there, not English, and have no problem following recommendations but neither drawing them straighter – but also no time for going into detail.
Changed ‘terzet’ → ‘trio’.