The main purpose of this package is twofold: i) to facilitate the developer's life, and ii) to provide to the users meaningful, useful error messages. These objectives are accomplished with a single function: check_arg. That function checks the arguments given by the user: it offers a compact syntax such that complex arguments can be simply stated by the developer. In turn, if the user provides an argument of the wrong type then an informative error message will be buit, stating the expected type and where the error comes from--saving the user quite some time in debugging.
Thus you can very easily make your package look professional with check_arg (checking arguments properly is professional).
It also offers a set of small tools to provide informative messages to the users. See stop_up and warn_up to throw errors and warnings in the appropriate location. There are many tools to form messages: enumerate_items to form textual list of elements (with many options including conjugating verbs, etc...), plural to conjugate verbs depending on the argument, and n_letter, n_th, n_times to write integers in words (which usually looks nicer).
To sum up in a few words, this package was created to enhance the user experience and facilitate package development.
Useful links:
Report bugs at https://github.com/lrberge/dreamerr/issues