fix

assistant_bot/yandex_ai.py

@@ -18,6 +18,30 @@ def describe_yandex_error(exc: Exception) -> str:
     return str(exc)
 
 
+def prepare_chat_messages(
+    messages: list[dict[str, str]],
+) -> list[dict[str, str]]:
+    """Convert messages to the format accepted by Yandex prompt templates."""
+    system_parts: list[str] = []
+    chat_messages: list[dict[str, str]] = []
+
+    for message in messages:
+        role = message.get("role", "user")
+        content = message.get("content", "")
+        if role == "system":
+            system_parts.append(content)
+        else:
+            chat_messages.append({"role": role, "content": content})
+
+    if system_parts:
+        chat_messages.insert(
+            0,
+            {"role": "system", "content": "\n\n".join(system_parts)},
+        )
+
+    return chat_messages
+
+
 def create_async_sdk(folder_id: str) -> Any:
     try:
         from yandex_ai_studio_sdk import AsyncAIStudio
@@ -83,13 +107,7 @@ class YandexAIClient:
         messages: list[dict[str, str]],
         json_mode: bool = False,
     ) -> str:
-        sdk_messages = [
-            {
-                "role": message.get("role", "user"),
-                "content": message.get("content", ""),
-            }
-            for message in messages
-        ]
+        sdk_messages = prepare_chat_messages(messages)
 
         try:
             completion = self._sdk.chat.completions(self.normalize_model(model))