# Adding documentation

In this guide, we'll walk through adding documentation for our [fully test](testing.md) [custom `Strong` component](creating.md).

We mainly document 2 things for each component, its purpose and its interface.

## Component purpose

A component's description and any notes worth mentioning (limitations, features, etc).

This is written in the stories mdx file.

[See writing stories](https://hsds.helpscout.com/?path=/docs/%F0%9F%8F%A0-welcome-4-writing-stories--page)

## Component interface

AKA props documentation, we use `defaultProps` and `propTypes` to document the component interface, this information is included directly in the component jsx file.

This documentation is automatically turned into a table inside storybook.

[See writing components](<(https://hsds.helpscout.com/?path=/docs/%F0%9F%8F%A0-welcome-3-writing-components--page)>)

## Next

Let's submit our component for [review](review.md)!
