@param is normally only used to document parameters for the function; in this case we actually call the cb, so the documentation can be associated with @param cb somewhat like this:

@param cb callback([object {
 +     *      commit: <commit hash>,
 +     *      prefix: <prefix>,
 +     *      title:  <title>
 +     *      status: <status> // 'perfect', 'skip', 'fail', or null
 +     *      skips:  <skip count>,
 +     *      fails:  <fails count>,
 +     *      errors: <errors count>
 +     *      }]), with the worst results first