PowerDesigner provides default model checks to verify the validity of states.
| 
                             Check  | 
                        
                             Description and Correction  | 
                    
|---|---|
| 
                             State name and code uniqueness  | 
                        
                             State names and codes must be unique in the classifier. Manual correction: Modify the duplicate name/code Automatic correction: Appends a number to the duplicate name/code  | 
                    
| 
                             Input transition missing  | 
                        
                             Each state must have at least one input transition. A state without an input transition cannot be reached. Manual correction: Add a transition linked to the state Automatic correction: None  | 
                    
| 
                             Composite state does not have any start  | 
                        
                             A composite state details the state behavior in a sub-statechart diagram. To be complete, this sub-statechart diagram requires a start. Manual correction: Add a start in the sub-statechart diagram, or deselect the Composite check box in the state property sheet Automatic correction: None  | 
                    
| 
                             Incorrect action order  | 
                        
                             The entry trigger events must be the first in the list of actions on a state. The exit trigger events must the last in the list. All other actions can be ordered without any constraint. Manual correction: Move all entry at the top of the list and all exit at the bottom Automatic correction: Moves all entry at the top of the list and all exit at the bottom  |