type
  TMvcTestMe = class(TMVCApplication)
  published
    procedure Test(
      const aCtxt: TRestServerUriContext
      );
  end;

procedure TMVCTestMe.Test(const aCtxt: TRestServerUriContext);
var
  a, b: double;
begin
  if UrlDecodeNeedParameters(aCtxt.Parameters, 'A,B') then
  begin
    while aCtxt.Parameters <> nil do
    begin
      UrlDecodeDouble(aCtxt.Parameters, 'A=', a);
      UrlDecodeDouble(aCtxt.Parameters, 'B=', b, @aCtxt.Parameters);
    end;
    aCtxt.Returns(['result', True, 'Sum', a+b]);
  end
  else
    aCtxt.Returns(['result', False], HTTP_BADREQUEST)
end;