diff --git a/extra/peg/peg-docs.factor b/extra/peg/peg-docs.factor
index d2ca353ba1..7b13e06d5a 100644
--- a/extra/peg/peg-docs.factor
+++ b/extra/peg/peg-docs.factor
@@ -159,4 +159,17 @@ HELP: delay
 { $description 
     "Delays the construction of a parser until it is actually required to parse. This " 
     "allows for calling a parser that results in a recursive call to itself. The quotation "
-    "should return the constructed parser." } ;
+    "should return the constructed parser and is called the first time the parser is run."
+    "The compiled result is memoized for future runs. See " { $link box } " for a word "
+    "that calls the quotation at compile time." } ;
+
+HELP: box
+{ $values 
+  { "quot" "a quotation" } 
+  { "parser" "a parser" } 
+}
+{ $description 
+    "Delays the construction of a parser until the parser is compiled. The quotation "
+    "should return the constructed parser and is called when the parser is compiled."
+    "The compiled result is memoized for future runs. See " { $link delay } " for a word "
+    "that calls the quotation at runtime." } ;