diff --git a/brozzler/job_schema.yml b/brozzler/job_schema.yml
index e9d2078..a8f4b4e 100644
--- a/brozzler/job_schema.yml
+++ b/brozzler/job_schema.yml
@@ -66,6 +66,8 @@ id:
 
 seeds:
   type: list
+  required: true
+  minlength: 1
   schema:
     type: dict
     schema: