This is an advanced-use feature, and likely not something you'll need to configure. What you probably want is the content types reference!
The text field represents a single line text input. It should be used for content values that are short strings: for example, a page title.

interface TextConfig extends FieldConfig {component: 'text'name: stringlabel?: stringdescription?: stringplaceholder?: string}
Option  | Description  | 
|---|---|
  | The name of the plugin component. Always   | 
  | The path to some value in the data being edited.  | 
  | A human readable label for the field. Defaults to the   | 
  | Description that expands on the purpose of the field or prompts a specific action. (Optional)  | 
  | Placeholder text to appear in the input when it empty. (Optional)  | 
This interfaces only shows the keys unique to the text field. Visit the Field Config docs for a complete list of options.
Below is an example of how a text field could be used to edit the title of a blog post.
const BlogPostForm = {fields: [{component: 'text',name: 'title',label: 'Title',description: 'Enter the title of the post here',placeholder: '...',},],}