diff --git a/apps/agent-worker/src/worker.ts b/apps/agent-worker/src/worker.ts
index 73a1c1e..ca2dc8f 100644
--- a/apps/agent-worker/src/worker.ts
+++ b/apps/agent-worker/src/worker.ts
@@ -1524,7 +1524,12 @@ export const sendWorkspaceMessage = async (
         throw new Error(`${agentFailurePrefix(claim)}:\n${result.output}`);
       }
     }
-	    if (isCodexLoginProfile(claim)) {
+    if (isCodexLoginProfile(claim)) {
+      if (!assistantContent.value.trim()) {
+        throw new Error(
+          'Codex completed without producing an assistant response.',
+        );
+      }
 	      await updateMessage({
 	        messageId: assistantMessageId,
         status: 'completed',