diff --git a/bluebox/utils/llm_serialization.py b/bluebox/utils/llm_serialization.py
index b550ce50..7b3b59ff 100644
--- a/bluebox/utils/llm_serialization.py
+++ b/bluebox/utils/llm_serialization.py
@@ -119,7 +119,7 @@ def _excluded_fields(model_cls: type[BaseModel]) -> frozenset[str]:
     return frozenset(
         name
         for name, info in model_cls.model_fields.items()
-        if any(isinstance(m, LLMExclude) for m in info.metadata)
+        if any(m is LLMExclude or isinstance(m, LLMExclude) for m in info.metadata)
     )
 
 
diff --git a/tests/unit/utils/test_llm_serialization.py b/tests/unit/utils/test_llm_serialization.py
index 1ce4b08d..ec8d818c 100644
--- a/tests/unit/utils/test_llm_serialization.py
+++ b/tests/unit/utils/test_llm_serialization.py
@@ -103,6 +103,33 @@ class NestedWithComputed(BaseModel):
     item: WithComputedField
 
 
+# --- Bare-class (LLMExclude without parens) variants -------------------------
+
+
+class BareSimple(BaseModel):
+    """Uses bare LLMExclude class instead of LLMExclude()."""
+    visible: str
+    hidden: Annotated[str, LLMExclude]
+
+
+class BareWithInstance(BaseModel):
+    """Mix of bare class and instance in the same model."""
+    keep: str
+    drop_bare: Annotated[str, LLMExclude]
+    drop_instance: Annotated[str, LLMExclude()]
+
+
+class BareNested(BaseModel):
+    name: str
+    inner: BareSimple
+    secret: Annotated[str, LLMExclude]
+
+
+class BareWithField(BaseModel):
+    name: str
+    internal_id: Annotated[int, Field(description="DB key"), LLMExclude]
+
+
 # =============================================================================
 # LLMExclude marker
 # =============================================================================
@@ -123,6 +150,11 @@ def test_not_on_regular_field(self) -> None:
         info = SimpleModel.model_fields["visible"]
         assert not any(isinstance(m, LLMExclude) for m in info.metadata)
 
+    def test_bare_class_stored_in_metadata(self) -> None:
+        """Annotated[str, LLMExclude] (no parens) stores the class itself."""
+        info = BareSimple.model_fields["hidden"]
+        assert any(m is LLMExclude for m in info.metadata)
+
 
 # =============================================================================
 # _excluded_fields
@@ -159,6 +191,15 @@ def test_result_is_cached(self) -> None:
         result2 = _excluded_fields(SimpleModel)
         assert result1 is result2  # same object from cache
 
+    def test_bare_class_detected(self) -> None:
+        assert _excluded_fields(BareSimple) == frozenset({"hidden"})
+
+    def test_bare_and_instance_both_detected(self) -> None:
+        assert _excluded_fields(BareWithInstance) == frozenset({"drop_bare", "drop_instance"})
+
+    def test_bare_with_pydantic_field(self) -> None:
+        assert _excluded_fields(BareWithField) == frozenset({"internal_id"})
+
 
 # =============================================================================
 # strip_llm_excluded — BaseModel inputs
@@ -267,6 +308,33 @@ def test_nested_model_with_computed_field(self) -> None:
             "item": {"first": "Jane", "last": "Doe", "full_name": "Jane Doe"},
         }
 
+    def test_bare_class_simple_model(self) -> None:
+        """Annotated[str, LLMExclude] (no parens) strips correctly."""
+        obj = BareSimple(visible="yes", hidden="no")
+        result = strip_llm_excluded(obj)
+        assert result == {"visible": "yes"}
+        assert "hidden" not in result
+
+    def test_bare_and_instance_mixed(self) -> None:
+        """Both bare-class and instance annotations strip in the same model."""
+        obj = BareWithInstance(keep="ok", drop_bare="gone1", drop_instance="gone2")
+        result = strip_llm_excluded(obj)
+        assert result == {"keep": "ok"}
+
+    def test_bare_class_nested(self) -> None:
+        inner = BareSimple(visible="kept", hidden="dropped")
+        obj = BareNested(name="test", inner=inner, secret="shh")
+        result = strip_llm_excluded(obj)
+        assert result == {
+            "name": "test",
+            "inner": {"visible": "kept"},
+        }
+
+    def test_bare_class_with_pydantic_field(self) -> None:
+        obj = BareWithField(name="widget", internal_id=999)
+        result = strip_llm_excluded(obj)
+        assert result == {"name": "widget"}
+
 
 # =============================================================================
 # strip_llm_excluded — dict / list / tuple / primitive inputs