--  with Ada.Real_Time;         use Ada.Real_Time; 

--  with Vectors_3D;            use Vectors_3D; 

package Vehicle_Message_Type is 

   -- Replace this record definition by whatever you actually need to communicate. 

   type Inter_Vehicle_Messages is record 

      Id : Positive; 

   end record; 

end Vehicle_Message_Type
To API doc
To spec;