SYNOPSIS use Git::Validate; my $validator = Git::Validate->new; my $errors = $validator->validate_commit('HEAD'); die "$errors\n" if $errors; Or if you want to be all classy and modern: for $e (@{$errors->errors}) { warn $e->line . " longer than " . $e->max_length . " characters!\n" if $e->isa('Git::Validate::Error::LongLine') } DESCRIPTION While many users apparently don't know it, there are actual correct ways to write a git commit message. For a good summary of why, read this blog post . This module does its best to automatically check commit messages against The Rules. The current automatic checks are: * First line should be 50 or fewer characters * Second line should be blank * Third and following lines should be less than 72 characters METHODS validate_commit my $errors = $validator->validate_commit('HEAD'); returns "ERRORS" for a given commit validate_message my $errors = $validator->validate_message($commit_message); returns "ERRORS" for a given message ERRORS The object containing errors conveniently stringifies and boolifies. If you need more information, please please please don't try to parse the returned strings. Instead, note that the errors returned are a set of objects. These are the objects you can check for: * Git::Validate::Error::LongLine * Git::Validate::Error::MissingBreak The objects can be accessed with the errors method, which returns an arrayref. The objects have line and line_number methods. The ::LongLine objects have a max_length method as well.