diff --git a/src/propeller/problems/PSB1/grade.cljc b/src/propeller/problems/PSB1/grade.cljc
index a8961aa..b2f2590 100644
--- a/src/propeller/problems/PSB1/grade.cljc
+++ b/src/propeller/problems/PSB1/grade.cljc
@@ -74,7 +74,9 @@
                            :cljs (apply + errors)))))
 
 (defn -main
-  "Runs propel-gp, giving it a map of arguments."
+  "Runs the top-level genetic programming function, giving it a map of 
+  arguments with defaults that can be overridden from the command line
+  or through a passed map."
   [& args]
   (gp/gp
    (merge
@@ -92,4 +94,4 @@
      :variation               {:umad 1.0 :crossover 0.0}
      :elitism                 false}
     (apply hash-map (map #(if (string? %) (read-string %) %) args))))
-  (#?(:clj shutdown-agents)))
\ No newline at end of file
+  (#?(:clj shutdown-agents)))