UUCP's task is to copy files from one system to another, and to request execution of certain commands on remote hosts. Of course, you as an administrator would want to control what rights you grant other systems-- allowing them to execute any command on your system is definitely not a good idea.
By default, the only commands Taylor UUCP allows other systems to execute on your machine are rmail and rnews, which are commonly used to to exchange email and Usent news over UUCP. The default search path used by uuxqt is a compile-time option, but should usually contain /bin, /usr/bin, and /usr/local/bin. To change the set of commands for a particular system, you can use the commands keyword in the sys file. Similarly, the search path can be changed with the command-path statement. For instance, you may want to allow system pablo to execute the rsmtp command in addition to rmail and rnews: