Some PropertyTypes can benefit from instruction parameters to be set for the field. For instance, it would be useful to indicate a limitation on the fields shown for a PropertyType.PERIOD property, by supplying a string such as d,h,m,s. This would disable any year, month or week components in the property view. This could be implemented in a number of ways, of which two seem the most plausible:
1) Specifying within the original annotation
@Property(type = PropertyType.PERIOD, parameters = "d,h,m,s")
2) Specifying by supplying an additional annotation
@Property(type = PropertyType.PERIOD)
@PropertyParameter(id = "fields", value = "d,h,m,s")
Benefits to the latter approach are visual separation and more freedom to specify a list because you can use multiple attributes without cluttering the @Property annotation any further.