Standard programming tools use a system of error messages and warnings to help programmers in finding syntax and logical errors in their programs. Generative programming differentiates the level of generator from the level of generated application. The source code is synthesized at the level of generator from a set of code templates according to application specification and rules defined by generator configuration. Code templates, application specification and generator configuration are mutually dependent and error in any part may result in incorrect source code. This paper deals with possibilities of introducing error messages that are specific at the level of generator. An example of generator is developed and discussed.