Cron jobs tend to run in a less "rich" environment, so you do need to be more explicit about things like paths. In particular, cron on (BSD-based) macosx uses "sh" instead of "bash", which means that the tilde is treated as just a tilde, not a special abbreviation for $HOME. However, cron will start you out in your home directory, so instead of tilde, you can just use period. Also, your PATH will be limited to "trusted" directories (not including ".") If your perl script begins with the standard shebang line:

#!/usr/bin/perl
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and if the current "mode flags" on the script file allow it to be executable (use the chmod +x to make the script executable), then your crontab entry can simply be:

23 13 * * * /absolute/path/to/script.pl
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(plus any args that the script might need for its @ARGV). Note that if the script writes anything to STDOUT or STDERR, this material will be sent to your mac login account as an email message (check out the unix "mail" command), unless your cron entry includes redirection on the command line, e.g.:

23 13 * * * ./mypath/to/script.pl > cron.out 2> cron.err
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In that example, "./" represents your home directory, which is where the output files will be created.