> This page is for SDK, version Legacy.
> For other versions, use one of these documentation indexes:
> - Current (default): https://buildwithfern.com/learn/sdks/current/llms.txt
> - Legacy: https://buildwithfern.com/learn/sdks/legacy/llms.txt

> For clean Markdown content of this page, append .md to this URL. For the complete documentation index, see https://buildwithfern.com/learn/llms.txt.

## 2.41.3

**`(feat):`** 为 SDK 构建器添加便捷的 `addHeader()` 方法，用于添加自定义头部，无需 OkHttpClient 自定义或继承。

## 2.41.2

**`(feat):`** 在 README.md 中链接 reference.md。