> For the complete documentation index, see [llms.txt](https://docs.blockchainsecurity.asia/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.blockchainsecurity.asia/documentation/he-xin-gai-nian.md).

# 核心概念

- [回應格式](https://docs.blockchainsecurity.asia/documentation/he-xin-gai-nian/response-format.md): 說明成功回應、錯誤回應、meta 欄位與 response header 的統一格式。
- [錯誤處理](https://docs.blockchainsecurity.asia/documentation/he-xin-gai-nian/errors.md): 統一的錯誤信封、錯誤碼與建議處理方式。
- [限流](https://docs.blockchainsecurity.asia/documentation/he-xin-gai-nian/rate-limiting.md): 說明 API key、endpoint 與方案層級的限流規則，以及超量時的回應方式。
- [Credit 計費](https://docs.blockchainsecurity.asia/documentation/he-xin-gai-nian/credit-billing.md): 說明 API credit 的扣點規則、餘額回傳、餘額不足處理與用量對帳方式。
- [分頁](https://docs.blockchainsecurity.asia/documentation/he-xin-gai-nian/pagination.md): 說明列表型 API 的 limit / offset 分頁規則、回應格式與翻頁方式。