diff --git a/src/replit_river/codegen/client.py b/src/replit_river/codegen/client.py
index 51fbf3dc..815d696c 100644
--- a/src/replit_river/codegen/client.py
+++ b/src/replit_river/codegen/client.py
@@ -535,7 +535,7 @@ def extract_props(tpe: RiverType) -> list[dict[str, RiverType]]:
                 type_name, _, contents, _ = encode_type(
                     prop,
                     TypeName(prefix.value + name.title()),
-                    base_model,
+                    "BaseModel" if base_model == "RiverError" else base_model,
                     in_module,
                     permit_unknown_members=permit_unknown_members,
                 )
diff --git a/tests/v1/codegen/snapshot/snapshots/test_unknown_enum/enumService/needsEnumObject.py b/tests/v1/codegen/snapshot/snapshots/test_unknown_enum/enumService/needsEnumObject.py
index dd61a2d7..2817a039 100644
--- a/tests/v1/codegen/snapshot/snapshots/test_unknown_enum/enumService/needsEnumObject.py
+++ b/tests/v1/codegen/snapshot/snapshots/test_unknown_enum/enumService/needsEnumObject.py
@@ -104,19 +104,19 @@ class NeedsenumobjectOutput(BaseModel):
 )
 
 
-class NeedsenumobjectErrorsFooAnyOf_0(RiverError):
+class NeedsenumobjectErrorsFooAnyOf_0(BaseModel):
     beep: Literal["err_first"] | None = None
 
 
-class NeedsenumobjectErrorsFooAnyOf_1(RiverError):
+class NeedsenumobjectErrorsFooAnyOf_1(BaseModel):
     borp: Literal["err_second"] | None = None
 
 
 NeedsenumobjectErrorsFoo = Annotated[
     NeedsenumobjectErrorsFooAnyOf_0
     | NeedsenumobjectErrorsFooAnyOf_1
-    | RiverUnknownError,
-    WrapValidator(translate_unknown_error),
+    | RiverUnknownValue,
+    WrapValidator(translate_unknown_value),
 ]