Procedure Editor has a separate places for editing procedure body and input/output parameters and local variables. Thus it separates procedure header and body. The list of input/output parameters and local variables is visible on the right side. Parameters are listed in order of their type (input, output, local). You could change the order of the parameters inside selected type (please check context menu for "Move Up" and "Move Down" commands). Unused parameters/variables are marked with exclamation mark:
The list of parameters can be temporarily hidden.
The Code Editor provides intelligent code completion and dynamic syntax and errors highlighting features. You can run SQL Debugger or execute your procedure with Query Analyzer. Page tabs on the left side provide additional information about stored procedure and includes: DDL Definition, Dependencies, Description and To-Do List.
When you change number of input parameters for existing procedure or change the position of output parameters Procedure Editor automatically calls "Add/Remove Parameter" refactoring. It allows you to update referenced objects automatically. If some input parameters were added you will be prompted for default values for these parameters.If you do not want any automatic processing you can turn off refactoring by unchecking correspondent flags.