diff --git a/src/models/disease.ts b/src/models/disease.ts
index 65079e66740c8eb2f4488a9f5798339cc9a4abe4..7152a107591c97797fb840aae640a4f49ac191d0 100644
--- a/src/models/disease.ts
+++ b/src/models/disease.ts
@@ -1,9 +1,9 @@
 import { z } from 'zod';
 
 export const disease = z.object({
-  link: z.string(),
+  id: z.number().int().positive(),
+  link: z.string().optional(),
   type: z.string(),
   resource: z.string(),
-  id: z.number(),
   annotatorClassName: z.string(),
 });
diff --git a/src/models/organism.ts b/src/models/organism.ts
index 4b003eefff187e85f7b27831e55d5c09ea3b5c62..f583456293d3886270327f55285aaa67d8cd90a6 100644
--- a/src/models/organism.ts
+++ b/src/models/organism.ts
@@ -1,9 +1,9 @@
 import { z } from 'zod';
 
 export const organism = z.object({
-  link: z.string(),
+  id: z.number().int().positive(),
+  link: z.string().optional(),
   type: z.string(),
   resource: z.string(),
-  id: z.number(),
   annotatorClassName: z.string(),
 });