API previews let you try out new endpoints and changes to existing endpoints before they become part of the official GitHub API.
During the preview period, we may change some features based on developer feedback. If we do make changes, we'll announce them on the developer blog without advance notice.
To access an API preview, you'll need to provide a custom media type in the
Accept header for your requests. Feature documentation for each preview specifies which custom media type to provide.
You can now provide more information in GitHub for URLs that link to registered domains by using the API to manage Content Attachments. For more information, see "Using content attachments."
Custom media types: