diff --git a/nlp/desci_sense/shared_functions/parsers/multi_reference_tagger.py b/nlp/desci_sense/shared_functions/parsers/multi_reference_tagger.py
index a9b2de60..8d38f3b4 100644
--- a/nlp/desci_sense/shared_functions/parsers/multi_reference_tagger.py
+++ b/nlp/desci_sense/shared_functions/parsers/multi_reference_tagger.py
@@ -37,7 +37,7 @@ class PromptCase(EnumDictKey):
 
 def return_fallback(input):
     return ParserChainOutput(
-        answer=[],
+        answer=Answer(sub_answers=list(), debug={"errors": "fallback"}),
         pparser_type=ParserChainType.MULTI_REF_TAGGER,
         extra={"errors": "fallback"},
     )
diff --git a/nlp/desci_sense/shared_functions/postprocessing/__init__.py b/nlp/desci_sense/shared_functions/postprocessing/__init__.py
index c3ad7302..a332f810 100644
--- a/nlp/desci_sense/shared_functions/postprocessing/__init__.py
+++ b/nlp/desci_sense/shared_functions/postprocessing/__init__.py
@@ -298,24 +298,30 @@ def convert_ref_tags_to_rdf_triplets(
             ]
     else:
         # non zero refs - add labels as predicates to corresponding urls
-        assert len(all_reference_tags) == len(reference_urls)
-        for ref_tags, ref_url in zip(all_reference_tags, reference_urls):
-            if len(ref_tags) == 0:
-                # if no ref tags provided, add default mention label
-                # add warning since this should be handled prior
-                logger.warning("No ref tags provided, adding default label!")
-                updated_ref_tags = [ontology.default_mention_label()]
-            else:
-                updated_ref_tags = ref_tags
-            for label in updated_ref_tags:
-                concept = ontology.get_concept_by_label(label)
-                assert concept.can_be_predicate()
-                triplets += [
-                    RDFTriplet(
-                        predicate=URIRef(concept.uri),
-                        object=URIRef(ref_url),
-                    )
-                ]
+        if len(all_reference_tags) == len(reference_urls):
+            for ref_tags, ref_url in zip(all_reference_tags, reference_urls):
+                if len(ref_tags) == 0:
+                    # if no ref tags provided, add default mention label
+                    # add warning since this should be handled prior
+                    logger.warning("No ref tags provided, adding default label!")
+                    updated_ref_tags = [ontology.default_mention_label()]
+                else:
+                    updated_ref_tags = ref_tags
+                for label in updated_ref_tags:
+                    concept = ontology.get_concept_by_label(label)
+                    assert concept.can_be_predicate()
+                    triplets += [
+                        RDFTriplet(
+                            predicate=URIRef(concept.uri),
+                            object=URIRef(ref_url),
+                        )
+                    ]
+        else:
+            logger.warning(
+                "No predictions in input corresponding to references!\n"
+                f"{all_reference_tags} != {reference_urls}"
+            )
+            # logger.warning(f"{all_reference_tags} != {reference_urls}")
     return triplets
 
     # # for each tag decide if it's the object or predicate
@@ -492,13 +498,17 @@ def get_support_data(
     ontology_interface: OntologyInterface,
     metadata_list: List[RefMetadata],
 ) -> ParserSupport:
-    md_dict = {}  # Initialize an empty dictionary
+    # Initialize an empty dictionary
+    md_dict = {}
 
     for m in metadata_list:
         if hasattr(m, "url"):
             md_dict[m.url] = m
 
-    return ParserSupport(ontology=ontology_interface, refs_meta=md_dict)
+    return ParserSupport(
+        ontology=ontology_interface,
+        refs_meta=md_dict,
+    )
 
 
 def post_process_firebase(