Format of Party strings

Is there a specification on the format of Party strings? After a while searching on the docs page I eventually found https://docs.daml.com/app-dev/grpc/proto-docs.html#allocatepartyrequest which points to daml/value.proto at 208d4a50daabf4f2059983efd024de7c405e69b7 · digital-asset/daml · GitHub. This gives a regex which is pretty much what I was looking for, but is there a limit on the length?

See What are the allowed characters and max length for DAML Party literals/names?.