diff --git a/client/src/utils/__tests__/schemaUtils.test.ts b/client/src/utils/__tests__/schemaUtils.test.ts
index 4c834fe..94e428a 100644
--- a/client/src/utils/__tests__/schemaUtils.test.ts
+++ b/client/src/utils/__tests__/schemaUtils.test.ts
@@ -51,13 +51,13 @@ describe("generateDefaultValue", () => {
 
   test("generates null for non-required primitive types", () => {
     expect(generateDefaultValue({ type: "string", required: false })).toBe(
-      null,
+      undefined,
     );
     expect(generateDefaultValue({ type: "number", required: false })).toBe(
-      null,
+      undefined,
     );
     expect(generateDefaultValue({ type: "boolean", required: false })).toBe(
-      null,
+      undefined,
     );
   });
 
diff --git a/client/src/utils/schemaUtils.ts b/client/src/utils/schemaUtils.ts
index ea92065..520b790 100644
--- a/client/src/utils/schemaUtils.ts
+++ b/client/src/utils/schemaUtils.ts
@@ -13,7 +13,7 @@ export function generateDefaultValue(schema: JsonSchemaType): JsonValue {
   if (!schema.required) {
     if (schema.type === "array") return [];
     if (schema.type === "object") return {};
-    return null;
+    return undefined;
   }
 
   switch (schema.type) {