diff --git a/user_guide_src/source/libraries/validation.rst b/user_guide_src/source/libraries/validation.rst
index 84e687324613..c9a7927c90fe 100644
--- a/user_guide_src/source/libraries/validation.rst
+++ b/user_guide_src/source/libraries/validation.rst
@@ -341,7 +341,10 @@ For example, data returned by multi select dropdown:
 Validate 1 Value
 ================
 
-Validate one value against the rules:
+The ``check()`` method validates one value against the rules.
+The first parameter ``$value`` is the value to validate. The second parameter
+``$rule`` is the validation rules.
+The optional third parameter ``$errors`` is the the custom error message.
 
 .. literalinclude:: validation/012.php