Add recommendation to avoid variable reflection methods

README.adoc

@@ -5742,6 +5742,54 @@ u2.send :sleep, 0
 u2.__send__ ...
 ----
 
+=== Avoid Variable Reflection Methods [[avoid-variable-reflection]]
+
+Avoid using Ruby's variable reflection methods. They break encapsulation and make code harder to understand and maintain.
+
+These methods include:
+
+* `instance_variable_get`
+* `instance_variable_set`
+* `instance_variable_defined?`
+* `instance_variables`
+* `remove_instance_variable`
+* `class_variable_get`
+* `class_variable_set`
+* `class_variable_defined?`
+* `class_variables`
+* `remove_class_variable`
+
+NOTE: These methods may be acceptable in framework/library code, testing utilities, serialization libraries, or debugging tools where generic object introspection is necessary.
+
+[source,ruby]
+----
+class Person
+  def initialize(name)
+    @name = name
+  end
+end
+
+person = Person.new('Alice')
+
+# bad - breaks encapsulation
+person.instance_variable_get(:@name)
+person.instance_variable_set(:@name, 'Bob')
+
+# good - use proper accessor methods
+class Person
+  attr_reader :name
+  attr_writer :name
+
+  def initialize(name)
+    @name = name
+  end
+end
+
+person = Person.new('Alice')
+person.name
+person.name = 'Bob'
+----
+
 == API Documentation [[api-documentation]]
 
 === YARD