diff --git a/src/ibek/ioc.py b/src/ibek/ioc.py
index 078559080..d568d35f0 100644
--- a/src/ibek/ioc.py
+++ b/src/ibek/ioc.py
@@ -27,9 +27,21 @@ class Entity(BaseSettings):
     )
     __definition__: Definition
 
-    @model_validator(mode="after")  # type: ignore
+    @model_validator(mode="before")  # type: ignore
     def add_ibek_attributes(cls, entity: Entity):
-        """Whole Entity model validation"""
+        """
+        Whole Entity model validation
+
+        TODO at present an object reference to an ID where the referred object violates
+        schema is seen as "KeyError: "object XXX not found in [...]" which hides the
+        schema violation error.
+
+        This could potentially be fixed by doing the validation here instead
+        (removing extra:forbid from the model_config). BUT, at present passing
+        the info arg to this function receives a dict of the IOC instance
+        that created this entity, not the entity itself. This may be a
+        pydantic bug?
+        """
 
         # find the id field in this Entity if it has one
         ids = set(a.name for a in entity.__definition__.args if isinstance(a, IdArg))
diff --git a/tests/samples/generate_samples.sh b/tests/samples/generate_samples.sh
index 322eff3ee..48fc228d7 100755
--- a/tests/samples/generate_samples.sh
+++ b/tests/samples/generate_samples.sh
@@ -13,6 +13,7 @@ export DEFS=${SAMPLES_DIR}/../../ibek-defs
 # this is so relative schema mode lines work
 cd $SAMPLES_DIR
 
+set -x
 echo making the support yaml schema
 ibek ibek-schema ${SAMPLES_DIR}/schemas/ibek.defs.schema.json