diff --git a/src/de/steamwar/command/AbstractTypeMapper.java b/src/de/steamwar/command/AbstractTypeMapper.java
index 0363cd0..040f303 100644
--- a/src/de/steamwar/command/AbstractTypeMapper.java
+++ b/src/de/steamwar/command/AbstractTypeMapper.java
@@ -50,4 +50,13 @@ public interface AbstractTypeMapper<K, T> extends AbstractValidator<K, T> {
     default Collection<String> tabCompletes(K sender, PreviousArguments previousArguments, String s) {
         return tabCompletes(sender, previousArguments.userArgs, s);
     }
+
+    /**
+     * Normalize the cache key by sender and user provided argument. <br>
+     * Note: The CommandSender can be null! <br>
+     * Returning null and the empty string are equivalent.
+     */
+    default String normalize(K sender, String s) {
+        return null;
+    }
 }
diff --git a/src/de/steamwar/command/CommandPart.java b/src/de/steamwar/command/CommandPart.java
index 5a056d2..926ad2a 100644
--- a/src/de/steamwar/command/CommandPart.java
+++ b/src/de/steamwar/command/CommandPart.java
@@ -165,7 +165,7 @@ class CommandPart<T> {
     }
 
     private Collection<String> tabCompletes(T sender, String[] args, List<Object> mappedArgs, int startIndex) {
-        return TabCompletionCache.tabComplete(sender, typeMapper, command, () -> {
+        return TabCompletionCache.tabComplete(sender, args[startIndex], (AbstractTypeMapper<Object, ?>) typeMapper, command, () -> {
             try {
                 return typeMapper.tabCompletes(sender, new PreviousArguments(Arrays.copyOf(args, startIndex), mappedArgs.toArray()), args[startIndex]);
             } catch (Throwable e) {
diff --git a/src/de/steamwar/command/TabCompletionCache.java b/src/de/steamwar/command/TabCompletionCache.java
index 6f2d0ff..4e50a18 100644
--- a/src/de/steamwar/command/TabCompletionCache.java
+++ b/src/de/steamwar/command/TabCompletionCache.java
@@ -51,6 +51,7 @@ public class TabCompletionCache {
     @AllArgsConstructor
     private static class Key {
         private Object sender;
+        private String arg;
         private AbstractTypeMapper<?, ?> typeMapper;
     }
 
@@ -61,9 +62,11 @@ public class TabCompletionCache {
         private Collection<String> tabCompletions;
     }
 
-    Collection<String> tabComplete(Object sender, AbstractTypeMapper<?, ?> typeMapper, AbstractSWCommand<?> command, Supplier<Collection<String>> tabCompleteSupplier) {
+    Collection<String> tabComplete(Object sender, String arg, AbstractTypeMapper<Object, ?> typeMapper, AbstractSWCommand<?> command, Supplier<Collection<String>> tabCompleteSupplier) {
         if (!cached.contains(typeMapper)) return tabCompleteSupplier.get();
-        Key key = global.contains(typeMapper) ? new Key(null, typeMapper) : new Key(sender, typeMapper);
+        String normalizedArg = typeMapper.normalize(sender, arg);
+        if (normalizedArg == null) normalizedArg = "";
+        Key key = global.contains(typeMapper) ? new Key(null, normalizedArg, typeMapper) : new Key(sender, normalizedArg, typeMapper);
         TabCompletions tabCompletions = tabCompletionCache.computeIfAbsent(key, ignore -> {
             return new TabCompletions(command, System.currentTimeMillis(), tabCompleteSupplier.get());
         });
diff --git a/testsrc/de/steamwar/command/CacheCommand.java b/testsrc/de/steamwar/command/CacheCommand.java
index 5057ffd..7cfdb72 100644
--- a/testsrc/de/steamwar/command/CacheCommand.java
+++ b/testsrc/de/steamwar/command/CacheCommand.java
@@ -41,7 +41,6 @@ public class CacheCommand extends TestSWCommand {
     @Cached
     @Mapper(value = "int", local = true)
     public AbstractTypeMapper<String, Integer> typeMapper() {
-        System.out.println("TypeMapper register");
         return new TestTypeMapper<Integer>() {
             @Override
             public Integer map(String sender, PreviousArguments previousArguments, String s) {
diff --git a/testsrc/de/steamwar/command/CacheCommandTest.java b/testsrc/de/steamwar/command/CacheCommandTest.java
index 122528f..4a6e183 100644
--- a/testsrc/de/steamwar/command/CacheCommandTest.java
+++ b/testsrc/de/steamwar/command/CacheCommandTest.java
@@ -36,6 +36,14 @@ public class CacheCommandTest {
         assertThat(tabCompletions1, is(equalTo(tabCompletions2)));
     }
 
+    @Test
+    public void testCachingWithDifferentMessages() {
+        CacheCommand cmd = new CacheCommand();
+        List<String> tabCompletions1 = cmd.tabComplete("test", "", new String[]{""});
+        List<String> tabCompletions2 = cmd.tabComplete("test", "", new String[]{"0"});
+        assertThat(tabCompletions1, is(equalTo(tabCompletions2)));
+    }
+
     @Test
     public void testCachingWithDifferentSenders() {
         CacheCommand cmd = new CacheCommand();