diff --git a/api/openapi.yaml b/api/openapi.yaml
index b039cba..fe305d8 100644
--- a/api/openapi.yaml
+++ b/api/openapi.yaml
@@ -97,8 +97,12 @@ paths:
                 $ref: '#/components/responses/CreateSessionsResponse'
         '400':
           $ref: '#/components/responses/ErrorResponse'
+        # Forbidden
         '403':
           $ref: '#/components/responses/ErrorResponse'
+        # Please contact, requires human interverntion
+        '422':
+          $ref: '#/components/responses/ErrorResponse'
 
     get:
       description: Lists a set of sessions visible to the caller. Each session in the set contains a summary of its current status.