文件索引太大了，超上下文，有什么办法呢？

HTTP 400: Bad Request — {"error":{"message":"***.ContextWindowExceededError: ***.BadRequestError: ContextWindowExceededError: OpenAIException - {\"object\":\"error\",\"message\":\"The input (1723391 tokens) is longer than the model's context length (524288 tokens).\",\"type\":\"BadRequestError\",\"param\":null,\"code\":400}\nmodel=XXXX","type":"upstream_error","param":"","code":"400"}}