diff --git a/packages/core/src/v3/apiClient/index.ts b/packages/core/src/v3/apiClient/index.ts
index deda5d01f9..e6f488bb9d 100644
--- a/packages/core/src/v3/apiClient/index.ts
+++ b/packages/core/src/v3/apiClient/index.ts
@@ -2375,7 +2375,7 @@ function shouldRetryStreamBatchItems(
 
   // Retry on rate limits with special handling for Retry-After
   if (response.status === 429) {
-    if (attempt >= retryOptions.maxAttempts!) {
+    if (retryOptions.maxAttempts !== undefined && attempt >= retryOptions.maxAttempts) {
       return { retry: false };
     }
 
diff --git a/packages/core/src/v3/utils/ioSerialization.ts b/packages/core/src/v3/utils/ioSerialization.ts
index 5502afb098..417386f7f8 100644
--- a/packages/core/src/v3/utils/ioSerialization.ts
+++ b/packages/core/src/v3/utils/ioSerialization.ts
@@ -31,7 +31,11 @@ export async function parsePacket(value: IOPacket, options?: ParsePacketOptions)
 
   switch (value.dataType) {
     case "application/json":
-      return JSON.parse(value.data, makeSafeReviver(options));
+      try {
+        return JSON.parse(value.data, makeSafeReviver(options));
+      } catch {
+        return undefined;
+      }
     case "application/super+json":
       return superjson.parse(value.data);
     case "text/plain":
@@ -55,7 +59,11 @@ export async function parsePacketAsJson(
 
   switch (value.dataType) {
     case "application/json":
-      return JSON.parse(value.data, makeSafeReviver(options));
+      try {
+        return JSON.parse(value.data, makeSafeReviver(options));
+      } catch {
+        return undefined;
+      }
     case "application/super+json":
       const superJsonResult = superjson.parse(value.data);