deepseek-ai/deepseek-harness · error · TypeError

{method} response must be a JSON object

Error message

{method} response must be a JSON object

What it means

Error "{method} response must be a JSON object" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at python/sdk/src/deepseek_harness/client.py:177

        method: str,
        params: JsonObject | None,
        *,
        response_model: type[ModelT],
        timeout_seconds: float | None = None,
        on_notification: Callable[[Notification], None] | None = None,
        notification_filter: NotificationFilter | None = None,
        notification_subscription: "NotificationSubscription | None" = None,
    ) -> ModelT:
        result = self._request_raw(
            method,
            params,
            timeout_seconds=timeout_seconds,
            on_notification=on_notification,
            notification_filter=notification_filter,
            notification_subscription=notification_subscription,
        )
        if not isinstance(result, dict):
            raise TypeError(f"{method} response must be a JSON object")
        return response_model.model_validate(result)

    def notify(self, method: str, params: JsonObject | None = None) -> None:
        message: JsonObject = {"jsonrpc": "2.0", "method": method}
        if params is not None:
            message["params"] = params
        self._write_message(message)

    def next_notification(self) -> Notification:
        item = self._notifications.get()
        if isinstance(item, BaseException):
            raise item
        return item

    def subscribe_notifications(
        self,
        notification_filter: NotificationFilter | None = None,
    ) -> "NotificationSubscription":

View on GitHub (pinned to b150a551b8)

Solutions

1. Check the runtime version matches the SDK protocol; the named method must return a JSON object response.

When it happens

Trigger: Thrown at python/sdk/src/deepseek_harness/client.py:177 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of deepseek-ai/deepseek-harness@b150a551b8 (2026-08-24). Data as JSON: /api/errors/1b5a81c4a6443eb2. Report an issue: GitHub.