Model Validation works against a set of validation rules, arranged in the following groups:
| · | (Element, Relationship, Feature, Diagram): Well-Formedness Checks whether or not an Element, Relationship, Feature or Diagram is well-formed. This group of rules includes checks such as whether the item is a valid UML item and whether a diagram contains valid elements within it |
| · | Element: Composition Checks whether or not a UML Element contains valid children, whether it contains the right number of valid children, and whether or not the element is missing any required children |
| · | (Element, Relationship, Feature): Property Validity Checks whether or not the item has the correct UML properties defined, and whether the properties contain incorrect or conflicting values; for more information on these properties see the Custom Properties topic |
| · | (Element, Relationship, Feature): OCL Conformance Validates an item against any defined constraints in OCL. |