General ⇒ modifying \newcommand for debugging

[lbutler]

Hi, I am managing a distributed project composed in LaTeX, using a book documentclass based on the standard book documentclass, with about 15 contributors. To ease my debugging problems, I would like all contributors to only define new macros in specific files. After these files are input, I would like to modify \newcommand (and friends) so that it emits a warning or error.

Are there pre-existing packages or hooks that would help me to do this?