diff --git a/biolink/datamodel/serializers.py b/biolink/datamodel/serializers.py
index 77b8dcf..3385fcd 100644
--- a/biolink/datamodel/serializers.py
+++ b/biolink/datamodel/serializers.py
@@ -333,7 +333,7 @@
 # text annotate
 token = api.model('Token', {
     'id': fields.String(description='The CURIE for the entity or token'),
-    'category': fields.List(fields.String, description='entity categories'),
+    'categories': fields.List(fields.String, description='entity categories'),
     'terms': fields.List(fields.String, description='terms')
 })
 
diff --git a/requirements.txt b/requirements.txt
index 1e82744..e6e67bc 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,7 +1,9 @@
 prefixcommons>=0.0
-ontobio>=2.7.14
+# ontobio>=2.7.14
+git+https://github.com/falquaddoomi/ontobio.git@7894361056bf87a69cacb8cefcf10ac4f51f2924#egg=ontobio
 pip>=9.0.1
 wheel>0.25.0
+itsdangerous==2.0.1
 Flask==1.1.2
 flask-restplus>=0.10.1
 Flask-SQLAlchemy>=2.1