"""Shared fallback messages for empty/failed responses.

All layers (ReActEngine, Portal, Chat) should use these constants
to ensure consistent user-facing messages.
"""

# When LLM returns empty content after all fallback models exhausted
EMPTY_LLM_RESPONSE = (
    "模型未返回有效内容，已尝试备用模型仍未成功。"
    "可能原因：1) 服务暂时过载；2) 请求内容超出模型处理范围。"
    "建议：1) 稍后重试；2) 简化或缩短输入内容。"
)

# When ReActEngine reaches max steps without a complete answer
MAX_STEPS_REACHED = "已达到最大推理步数，但仍未得到完整结论。建议：1) 简化问题后重试；2) 将任务拆分为更小的步骤。"

# When a shell command succeeds but produces no output
SHELL_NO_OUTPUT = "[命令执行成功，无输出内容]"
