ScoreDefinitionType is the real score type enum:
https://github.com/droolsjbpm/optaplanner/blob/master/optaplanner-core/src/main/java/org/optaplanner/core/config/score/definition/ScoreDefinitionType.java
I can add methods on that one, like
boolean isBendable()
boolean isOkToUseInWorkbench()
etc

these are the copy pastes of that:

• ScoreDefinitionTypeModel https://github.com/droolsjbpm/optaplanner-wb/blob/master/optaplanner-wb-screens/optaplanner-wb-solver-editor/optaplanner-wb-solver-editor-api/src/main/java/org/optaplanner/workbench/screens/solver/model/ScoreDefinitionTypeModel.java
• PlannerDomainTypes https://github.com/droolsjbpm/optaplanner-wb/blob/master/optaplanner-wb-screens/optaplanner-wb-domain-editor/optaplanner-wb-domain-editor-client/src/main/java/org/optaplanner/workbench/screens/domaineditor/client/util/PlannerDomainTypes.java#L24

There should be only 1 if possible.
Because this is often used in a combobox, it needs to be i18ned so HARD_SOFT_SCORE becomes "Hard and soft score" or "Dur et gentille ..."

To make it @Portable without changing optaplanner-core, we can make a class @Portable by including a Errai.properties file in the JAR e.g. https://github.com/droolsjbpm/drools/blob/master/drools-workbench-models/drools-workbench-models-datamodel-api/src/main/resources/ErraiApp.properties (thanks to manstis for info)