diff --git a/mrbgems/mruby-range-ext/mrblib/range.rb b/mrbgems/mruby-range-ext/mrblib/range.rb
index 7fc05c190..10c0cde62 100644
--- a/mrbgems/mruby-range-ext/mrblib/range.rb
+++ b/mrbgems/mruby-range-ext/mrblib/range.rb
@@ -53,6 +53,19 @@ class Range
     return self.to_a.last(nv)
   end
 
+  ##
+  # call-seq:
+  #    rng.max                   -> obj
+  #    rng.max {|a,b| block }    -> obj
+  #
+  # Returns the maximum value in the range. Returns nil if the range is empty
+  # or excludes its end and the end is not an Integer. For non-numeric ranges
+  # or when a block is given, it delegates to Enumerable#max.
+  #
+  #   (10..20).max      #=> 20
+  #   (10...20).max     #=> 19
+  #   ('a'..'z').max    #=> "z"
+  #
   def max(&block)
     val = self.begin
     last = self.end
@@ -75,6 +88,17 @@ class Range
     super()
   end
 
+  ##
+  # call-seq:
+  #    rng.min                   -> obj
+  #    rng.min {|a,b| block }    -> obj
+  #
+  # Returns the minimum value in the range. For non-numeric ranges or when
+  # a block is given, it delegates to Enumerable#min.
+  #
+  #   (10..20).min      #=> 10
+  #   ('a'..'z').min    #=> "a"
+  #
   def min(&block)
     val = self.begin
     last = self.end
@@ -97,9 +121,16 @@ class Range
     super()
   end
 
-  # Compare two ranges and see if they overlap each other
-  #  (1..5).overlap?(4..6) # => true
-  #  (1..5).overlap?(7..9) # => false
+  ##
+  # call-seq:
+  #    rng.overlap?(other_range) -> true or false
+  #
+  # Returns true if self and other_range have at least one element in common,
+  # false otherwise.
+  #
+  #   (1..5).overlap?(4..6) #=> true
+  #   (1..5).overlap?(7..9) #=> false
+  #
   def overlap?(other)
     raise TypeError, "argument must be a range" unless other.kind_of?(Range)
 
diff --git a/mrbgems/mruby-range-ext/src/range.c b/mrbgems/mruby-range-ext/src/range.c
index 8b293a4de..4eb12cd4b 100644
--- a/mrbgems/mruby-range-ext/src/range.c
+++ b/mrbgems/mruby-range-ext/src/range.c
@@ -19,14 +19,14 @@ r_less(mrb_state *mrb, mrb_value a, mrb_value b, mrb_bool excl)
 
 /*
  *  call-seq:
- *     rng.cover?(obj)  ->  true or false
+ *     rng.cover?(obj)   -> true or false
  *     rng.cover?(range) -> true or false
  *
- *  Returns +true+ if the given argument is within +self+, +false+ otherwise.
+ *  Returns true if the given argument is within self, false otherwise.
  *
- *  With non-range argument +object+, evaluates with <tt><=</tt> and <tt><</tt>.
+ *  With non-range argument object, evaluates with <= and <.
  *
- *  For range +self+ with included end value (<tt>#exclude_end? == false</tt>),
+ *  For range self with included end value (exclude_end? == false),
  *  evaluates thus:
  *
  *    self.begin <= object <= self.end
@@ -193,6 +193,13 @@ range_size(mrb_state *mrb, mrb_value range)
 }
 #endif /* MRB_NO_FLOAT */
 
+/*
+ * Internal helper method to check if a range would be empty given
+ * the specified begin, end, and exclude_end parameters.
+ * Returns true if the range would be empty, false otherwise.
+ * Used internally by overlap? and other range methods.
+ */
+
 static mrb_value
 range_empty_p(mrb_state *mrb, mrb_value range)
 {