It would be extremely useful if JMX's Standard MBeans could include
a description for attributes, operations, and parameters. Currently,
descriptions are possible with Dynamic MBeans but not Standard ones.

The metadata language feature defined by JSR 175 would be ideal
for this purpose.

The proposed tag would be @Description. It could be defined either as
a general-purpose tag in, e.g., java.lang.metadata, or as a JMX-specific
tag in javax.management. The definition would be this:

@Documented @RuntimeVisible
public @interface Description {
    String value();
}

Additionally, but less importantly, a JMX-specific tag could
describe the impact of an operation (INFO, ACTION, ACTION_INFO),
as defined by MBeanOperationInfo.getImpact():

@Documented @RuntimeVisible @Target({ElementType.METHOD})
public @interface OperationImpact {
    int value();
}

This would be in javax.management.