diff --git a/src/experimaestro/core/types.py b/src/experimaestro/core/types.py
index 6a8fd06d..b507edaa 100644
--- a/src/experimaestro/core/types.py
+++ b/src/experimaestro/core/types.py
@@ -60,6 +60,12 @@ def __hash__(self):
     def __eq__(self, other):
         return other.name.__eq__(self.name)
 
+    def __getstate__(self):
+        return self.name
+
+    def __setstate__(self, state):
+        self.name = state
+
     def __getattr__(self, key):
         return self(key)
 
diff --git a/src/experimaestro/notifications.py b/src/experimaestro/notifications.py
index 798bbf1b..ccd285c7 100644
--- a/src/experimaestro/notifications.py
+++ b/src/experimaestro/notifications.py
@@ -153,6 +153,9 @@ def progress(value: float, level=0, desc: Optional[str] = None, console=False):
     if TaskEnv.instance().slave:
         # Skip if in a slave process
         return
+    if TaskEnv.instance().taskpath is None:
+        # Skip progress reporting if running outside an experimaestro task (e.g. unit tests or standalone scripts)
+        return
     Reporter.instance().set_progress(value, level, desc, console=console)
 
 
diff --git a/src/experimaestro/tests/test_grid_validation.py b/src/experimaestro/tests/test_grid_validation.py
index a7d49be7..bf42fd01 100644
--- a/src/experimaestro/tests/test_grid_validation.py
+++ b/src/experimaestro/tests/test_grid_validation.py
@@ -2,7 +2,7 @@
 from experimaestro.experiments.grid import GridSearch, GenericParams
 from experimaestro.experiments.configuration import ConfigurationBase, configuration
 from experimaestro.utils.config import validate_attrs
-
+import pytest
 
 @configuration()
 class SubConfig:
@@ -166,3 +166,14 @@ class CustomConfig(ConfigurationBase):
 
     assert tags[0] == {"lr": 0.05, "batch_size": 16}
     assert tags[1] == {"lr": 0.005, "batch_size": 64}
+
+
+def test_error_attrs_raises_on_unrecognized_keys():
+    data = {
+        "id": "test",
+        "lr": 0.05,
+        "unexpected_key_xyz": 123,
+    }
+
+    with pytest.raises(ValueError, match="unexpected_key_xyz"):
+        validate_attrs(MainConfig, data)
diff --git a/src/experimaestro/tests/test_objects.py b/src/experimaestro/tests/test_objects.py
index c1672cd8..27c04bf0 100644
--- a/src/experimaestro/tests/test_objects.py
+++ b/src/experimaestro/tests/test_objects.py
@@ -438,4 +438,3 @@ def test_field_names_and_load_objects_missing_defaults():
     # In-place mutations on default containers work as expected
     inst.items.append("test")
     assert inst.items == ["test"]
-
diff --git a/src/experimaestro/tests/test_serializers.py b/src/experimaestro/tests/test_serializers.py
index 712a97cf..ac9e3ca7 100644
--- a/src/experimaestro/tests/test_serializers.py
+++ b/src/experimaestro/tests/test_serializers.py
@@ -257,8 +257,7 @@ def test_taskstub_serialization_roundtrip():
     [reloaded_config] = from_state_dict(data2, partial_loading=False)
     assert isinstance(reloaded_config.__xpm__.task, TaskStub)
     assert (
-        reloaded_config.__xpm__.task.identifier
-        == loaded_config.__xpm__.task.identifier
+        reloaded_config.__xpm__.task.identifier == loaded_config.__xpm__.task.identifier
     )
     assert reloaded_config.__xpm__.task.typename == loaded_config.__xpm__.task.typename
 
diff --git a/src/experimaestro/utils/config.py b/src/experimaestro/utils/config.py
index 4fb92a13..3a89949c 100644
--- a/src/experimaestro/utils/config.py
+++ b/src/experimaestro/utils/config.py
@@ -157,11 +157,11 @@ def wrap_type(t: Any) -> Any:
     # Create a dynamic Pydantic model
     PydanticModel = create_model(
         cls.__name__,
-        __config__=ConfigDict(extra="allow", arbitrary_types_allowed=True),
+        __config__=ConfigDict(extra="forbid", arbitrary_types_allowed=True),
         **model_fields,
     )
 
-    # Validate
+    # Validate - will raise ValidationError if invalid keys or types are present
     validated_model = PydanticModel(**data)
 
     # Extract only the fields that the attrs class expects