// 优化前（约500 tokens）：
You are a helpful, respectful and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should be verbose, detailed and comprehensive, providing multiple examples, explanations and references whenever possible. If a question is unclear or not factually coherent, explain why instead of answering something not correct. If you're unsure of the answer, share your uncertainty and explain what you know, without making up information.

// 优化后（约150 tokens）：
You are helpful, respectful and honest. Answer helpfully while being safe. If unsure, admit uncertainty. Don't make up information.

// 对话历史管理示例代码
function manageConversationHistory(messages, maxTokens = 4000) {
  // 当对话长度超过阈值时
  if (estimateTokens(messages) > maxTokens) {
    const recentMessages = messages.slice(-4); // 保留最新的4条消息
    
    // 生成早期对话摘要
    const earlierMessages = messages.slice(0, -4);
    const summary = summarizeMessages(earlierMessages);
    
    // 用摘要替换早期对话
    return [
      { role: "system", content: "Earlier conversation summary: " + summary },
      ...recentMessages
    ];
  }
  return messages;
}

// 使用响应格式控制和max_tokens
const response = await openai.chat.completions.create({
  model: "gpt-4o",
  messages: [
    { role: "system", content: "简洁回答，使用JSON格式输出" },
    { role: "user", content: "分析以下文本的情感和关键词：" + userInput }
  ],
  max_tokens: 150,
  response_format: { type: "json_object" }
});