diff --git a/db/migrations/021_writer_contract_no_empty_response.sql b/db/migrations/021_writer_contract_no_empty_response.sql
new file mode 100644
index 0000000..3f49cc0
--- /dev/null
+++ b/db/migrations/021_writer_contract_no_empty_response.sql
@@ -0,0 +1,19 @@
+UPDATE app_settings
+SET value_json = to_jsonb($contract$
+OUTPUT SCHEMA (return array matching input order):
+{"rewrites":[{"id":123,"category_id":2,"text":"готовый текст без хэштегов","notes":"короткая заметка для редактора или null"}]}
+
+Rules:
+- Input is a JSON object with key "posts" containing accepted posts.
+- Input has key "categories" with objects: id, name, tag.
+- Each post includes producer_name and producer_tag. producer_name can be a manufacturer, shop, or publishing source.
+- Pick exactly one category from the categories list in input and return its numeric id as category_id.
+- Do not add links or hashtags to rewritten text.
+- Return JSON only. No markdown. No text outside JSON.
+- Never return an empty object. Never omit the "rewrites" key.
+- Return one rewrite for every input post id.
+- The "text" field must be a ready-to-publish Russian post with normal paragraph line breaks encoded as JSON string newlines.
+- The "notes" field must be a short editor note in Russian or null.
+$contract$::text),
+updated_at = NOW()
+WHERE key='ai_writer_contract';
diff --git a/src/vk_parser_app/workers/ai_writer.py b/src/vk_parser_app/workers/ai_writer.py
index 7614b2b..264185c 100644
--- a/src/vk_parser_app/workers/ai_writer.py
+++ b/src/vk_parser_app/workers/ai_writer.py
@@ -41,6 +41,7 @@ Rules:
 - Pick exactly one category from the categories list in input and return its numeric id as category_id.
 - Do not add links or hashtags to rewritten text.
 - Return JSON only. No markdown. No text outside JSON.
+- Never return an empty object. Never omit the "rewrites" key.
 - Return one rewrite for every input post id.
 - The "text" field must be a ready-to-publish Russian post with normal paragraph line breaks encoded as JSON string newlines.
 - The "notes" field must be a short editor note in Russian or null.
@@ -434,6 +435,8 @@ class AIWriterWorker:
             for p in posts
         }
         batch_id = await self.create_batch(provider, model, prompt, payload)
+        response = None
+        usage = None
         try:
             response, usage = await self.call_ai(provider, model, api_key, api_base, prompt, payload, temperature, timeout)
             rewrites = validate_rewrites(response, set(post_ids), categories, source_tags_by_id)
@@ -443,7 +446,7 @@ class AIWriterWorker:
             return True
         except Exception as exc:
             await self.mark_posts_failed(post_ids, str(exc))
-            await self.finish_batch(batch_id, "failed", error=str(exc))
+            await self.finish_batch(batch_id, "failed", response=response, error=str(exc), usage=usage)
             logger.exception("AI writer batch failed: id={} error={}", batch_id, exc)
             return True