diff --git a/src/de/steamwar/command/AbstractSWCommand.java b/src/de/steamwar/command/AbstractSWCommand.java
index 9b0264f..892d804 100644
--- a/src/de/steamwar/command/AbstractSWCommand.java
+++ b/src/de/steamwar/command/AbstractSWCommand.java
@@ -67,7 +67,8 @@ public abstract class AbstractSWCommand<T> {
         System.out.println(message.get());
     }
 
-    protected void sendMessage(T sender, String message, Object[] args) {}
+    protected void sendMessage(T sender, String message, Object[] args) {
+    }
 
     protected final void execute(T sender, String alias, String[] args) {
         initialize();
@@ -91,7 +92,7 @@ public abstract class AbstractSWCommand<T> {
                 .filter(Objects::nonNull)
                 .flatMap(Collection::stream)
                 .filter(s -> !s.isEmpty())
-                .filter(s -> s.toLowerCase().startsWith(string))
+                .filter(s -> s.toLowerCase().startsWith(string) || string.startsWith(s.toLowerCase()))
                 .distinct()
                 .collect(Collectors.toList());
     }
@@ -150,7 +151,8 @@ public abstract class AbstractSWCommand<T> {
         if (!checkType(method.getAnnotations(), method.getReturnType(), annotation -> {
             CommandMetaData.Method methodMetaData = annotation.annotationType().getAnnotation(CommandMetaData.Method.class);
             if (methodMetaData == null) return aClass -> true;
-            if (method.getParameterCount() > methodMetaData.maxParameterCount() || method.getParameterCount() < methodMetaData.minParameterCount()) return aClass -> false;
+            if (method.getParameterCount() > methodMetaData.maxParameterCount() || method.getParameterCount() < methodMetaData.minParameterCount())
+                return aClass -> false;
             return aClass -> {
                 Class<?>[] types = methodMetaData.value();
                 if (types == null) return true;
@@ -171,7 +173,8 @@ public abstract class AbstractSWCommand<T> {
                 if (Predicate.class.isAssignableFrom(handler)) {
                     try {
                         return (Predicate<Class<?>>) handler.getConstructor().newInstance();
-                    } catch (InstantiationException | IllegalAccessException | InvocationTargetException | NoSuchMethodException e) {
+                    } catch (InstantiationException | IllegalAccessException | InvocationTargetException |
+                             NoSuchMethodException e) {
                     }
                 }
                 return aClass -> {
@@ -318,7 +321,9 @@ public abstract class AbstractSWCommand<T> {
     @CommandMetaData.Method(value = AbstractTypeMapper.class, maxParameterCount = 0)
     protected @interface Cached {
         long cacheDuration() default 5;
+
         TimeUnit timeUnit() default TimeUnit.SECONDS;
+
         boolean global() default false;
     }
 
@@ -378,7 +383,7 @@ public abstract class AbstractSWCommand<T> {
          */
         boolean allowISE() default false;
 
-        int[] falseValues() default { 0 };
+        int[] falseValues() default {0};
 
         class Handler<T> implements AbstractTypeMapper<T, Object> {
 
@@ -416,11 +421,6 @@ public abstract class AbstractSWCommand<T> {
                 return inner.map(sender, previousArguments, s);
             }
 
-            @Override
-            public boolean validate(T sender, Object value, MessageSender messageSender) {
-                return inner.validate(sender, value, messageSender);
-            }
-
             @Override
             public Collection<String> tabCompletes(T sender, PreviousArguments previousArguments, String s) {
                 return inner.tabCompletes(sender, previousArguments, s);
@@ -446,7 +446,7 @@ public abstract class AbstractSWCommand<T> {
 
     @Retention(RetentionPolicy.RUNTIME)
     @Target({ElementType.PARAMETER})
-    @CommandMetaData.ImplicitValidator(handler = ErrorMessage.Handler.class, order = 1)
+    @CommandMetaData.ImplicitValidator(handler = ErrorMessage.Handler.class, order = 2)
     protected @interface ErrorMessage {
         /**
          * Error message to be displayed when the parameter is invalid.
@@ -486,11 +486,14 @@ public abstract class AbstractSWCommand<T> {
     @Retention(RetentionPolicy.RUNTIME)
     @Target({ElementType.PARAMETER})
     @CommandMetaData.Parameter({int.class, Integer.class, long.class, Long.class, float.class, Float.class, double.class, Double.class})
-    @CommandMetaData.ImplicitValidator(handler = Min.Handler.class, order = 2)
+    @CommandMetaData.ImplicitValidator(handler = Min.Handler.class, order = 3)
     protected @interface Min {
         int intValue() default Integer.MIN_VALUE;
+
         long longValue() default Long.MIN_VALUE;
+
         float floatValue() default Float.MIN_VALUE;
+
         double doubleValue() default Double.MIN_VALUE;
 
         boolean inclusive() default true;
@@ -507,6 +510,7 @@ public abstract class AbstractSWCommand<T> {
 
             @Override
             public boolean validate(T sender, Number value, MessageSender messageSender) {
+                if (value == null) return true;
                 return (comparator.apply(value).intValue()) >= this.value;
             }
         }
@@ -515,11 +519,14 @@ public abstract class AbstractSWCommand<T> {
     @Retention(RetentionPolicy.RUNTIME)
     @Target({ElementType.PARAMETER})
     @CommandMetaData.Parameter({int.class, Integer.class, long.class, Long.class, float.class, Float.class, double.class, Double.class})
-    @CommandMetaData.ImplicitValidator(handler = Max.Handler.class, order = 2)
+    @CommandMetaData.ImplicitValidator(handler = Max.Handler.class, order = 3)
     protected @interface Max {
         int intValue() default Integer.MAX_VALUE;
+
         long longValue() default Long.MAX_VALUE;
+
         float floatValue() default Float.MAX_VALUE;
+
         double doubleValue() default Double.MAX_VALUE;
 
         boolean inclusive() default true;
@@ -536,6 +543,7 @@ public abstract class AbstractSWCommand<T> {
 
             @Override
             public boolean validate(T sender, Number value, MessageSender messageSender) {
+                if (value == null) return true;
                 return (comparator.apply(value).intValue()) <= this.value;
             }
         }
@@ -560,6 +568,7 @@ public abstract class AbstractSWCommand<T> {
     @CommandMetaData.ImplicitTypeMapper(handler = Length.Handler.class)
     protected @interface Length {
         int min() default 0;
+
         int max() default Integer.MAX_VALUE;
 
         class Handler<T> implements AbstractTypeMapper<T, Object> {
@@ -603,11 +612,14 @@ public abstract class AbstractSWCommand<T> {
     @Retention(RetentionPolicy.RUNTIME)
     @Target({ElementType.PARAMETER})
     @CommandMetaData.Parameter(handler = ArrayLength.Type.class)
-    @CommandMetaData.ImplicitValidator(handler = ArrayLength.Handler.class, order = 2)
+    @CommandMetaData.ImplicitValidator(handler = ArrayLength.Handler.class, order = 1)
     protected @interface ArrayLength {
         int min() default 0;
+
         int max() default Integer.MAX_VALUE;
 
+        String errorMessage() default "";
+
         class Type implements Predicate<Class<?>> {
             @Override
             public boolean test(Class<?> clazz) {
@@ -619,17 +631,26 @@ public abstract class AbstractSWCommand<T> {
 
             private int min;
             private int max;
+            private String errorMessage;
 
             public Handler(ArrayLength arrayLength) {
                 this.min = arrayLength.min();
                 this.max = arrayLength.max();
+                this.errorMessage = arrayLength.errorMessage();
+                if (this.errorMessage.isEmpty()) {
+                    this.errorMessage = null;
+                }
             }
 
             @Override
             public boolean validate(T sender, Object value, MessageSender messageSender) {
-                if (value == null) return false;
+                if (value == null) return true;
                 int length = Array.getLength(value);
-                return length >= min && length <= max;
+                boolean valid = length >= min && length <= max;
+                if (errorMessage != null) {
+                    messageSender.send(!valid, errorMessage);
+                }
+                return valid;
             }
         }
     }
diff --git a/src/de/steamwar/command/CommandPart.java b/src/de/steamwar/command/CommandPart.java
index b902892..8a45791 100644
--- a/src/de/steamwar/command/CommandPart.java
+++ b/src/de/steamwar/command/CommandPart.java
@@ -181,6 +181,7 @@ class CommandPart<T> {
         } catch (Exception e) {
             return new CheckArgumentResult(false, null);
         }
+        boolean success = true;
         for (AbstractValidator<T, Object> validator : validators) {
             try {
                 if (!validator.validate(sender, value, (s, objects) -> {
@@ -188,13 +189,14 @@ class CommandPart<T> {
                         command.sendMessage(sender, s, objects);
                     });
                 })) {
-                    return new CheckArgumentResult(false, null);
+                    success = false;
+                    value = null;
                 }
             } catch (Throwable e) {
                 throw CommandFrameworkException.commandPartExceptions("validating", e, args[index], (varArgType != null ? varArgType : parameter.getType()), parameter.getDeclaringExecutable(), parameterIndex);
             }
         }
-        return new CheckArgumentResult(true, value);
+        return new CheckArgumentResult(success, value);
     }
 
     public Class<?> getType() {
diff --git a/testsrc/de/steamwar/command/ArgumentCommand.java b/testsrc/de/steamwar/command/ArgumentCommand.java
index a107270..48f9b40 100644
--- a/testsrc/de/steamwar/command/ArgumentCommand.java
+++ b/testsrc/de/steamwar/command/ArgumentCommand.java
@@ -57,4 +57,19 @@ public class ArgumentCommand extends TestSWCommand {
     public void argument(String sender, String arg) {
         throw new ExecutionIdentifier("RunArgument with String");
     }
+
+    @Register
+    public void minLengthArgument(String sender, @Length(min = 3) @StaticValue({"he", "hello"}) String arg) {
+        throw new ExecutionIdentifier("RunLengthArgument with String");
+    }
+
+    @Register
+    public void minAndMaxLengthArgument(String sender, @Length(min = 3, max = 3) @StaticValue({"wo", "world"}) String arg) {
+        throw new ExecutionIdentifier("RunLengthArgument with String");
+    }
+
+    @Register
+    public void arrayLengthArgument(String sender, @ArrayLength(min = 2) int... args) {
+        throw new ExecutionIdentifier("RunArrayLengthArgument with Integer");
+    }
 }
diff --git a/testsrc/de/steamwar/command/ArgumentCommandTest.java b/testsrc/de/steamwar/command/ArgumentCommandTest.java
index 0af9327..5450c6e 100644
--- a/testsrc/de/steamwar/command/ArgumentCommandTest.java
+++ b/testsrc/de/steamwar/command/ArgumentCommandTest.java
@@ -98,7 +98,7 @@ public class ArgumentCommandTest {
     public void testTabComplete() {
         ArgumentCommand cmd = new ArgumentCommand();
         List<String> strings = cmd.tabComplete("test", "", new String[]{""});
-        assertTabCompletes(strings, "true", "false");
+        assertTabCompletes(strings, "true", "false", "hello", "wor");
     }
 
     @Test
@@ -106,5 +106,20 @@ public class ArgumentCommandTest {
         ArgumentCommand cmd = new ArgumentCommand();
         List<String> strings = cmd.tabComplete("test", "", new String[]{"t"});
         assertTabCompletes(strings, "true", "t");
+
+        strings = cmd.tabComplete("test", "", new String[]{"h"});
+        assertTabCompletes(strings, "h", "hello");
+
+        strings = cmd.tabComplete("test", "", new String[]{"hel"});
+        assertTabCompletes(strings, "hel", "hello");
+
+        strings = cmd.tabComplete("test", "", new String[]{"w"});
+        assertTabCompletes(strings, "w", "wor");
+
+        strings = cmd.tabComplete("test", "", new String[]{"wor"});
+        assertTabCompletes(strings, "wor");
+
+        strings = cmd.tabComplete("test", "", new String[]{"worl"});
+        assertTabCompletes(strings, "wor", "worl");
     }
 }