> For the complete documentation index, see [llms.txt](https://docs.langstack.com/welcome/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.langstack.com/welcome/get-started/learn-langstack/introduction-to-rest-api/headers/how-to-create-and-work-with-headers.md).

# How to create and work with Headers

* To create a Header: 
  * Go to the Inputs & outputs tab. 
  * Click the \[+ Header] button in the Parameters>Headers section.

{% embed url="<https://media.langstack.com/documentation/media/images/code/training_manual/chapter_4/ch4addheader.png>" %}

* To copy a Header, click the clipboard icon in the top right corner. \
  When a Header is copied, note that the header name and URL header names are updated to “(copied header name)\_copy\_1” e.g., if a header with the name “headerresponse” is copied, the copied header will automatically have the name as “headerresponse\_copy\_1”. This is to ensure that the header name remains unique. \
  The header name is editable.

{% embed url="<https://media.langstack.com/documentation/media/images/code/training_manual/chapter_4/ch4copyheader.png>" %}

* To expand or collapse a Header, click the arrow in the top right corner.

{% embed url="<https://media.langstack.com/documentation/media/images/code/training_manual/chapter_4/ch4expandheader.png>" %}

* To delete a Header, click the (x) in the top right corner.

{% embed url="<https://media.langstack.com/documentation/media/images/code/training_manual/chapter_4/ch4delheader.png>" %}

**Example of Header in Request**

`Cache-Control: no-cache`&#x20;

`Connection: Closed`&#x20;

`Content-Type: application/json`&#x20;

`Content-Length: 16`