Sometimes much longer 
Remember to add a website link in your YT channel (Customization - Basic info - Links)
and maybe on every video description.
You can use AI to generate some introductory text for your website, if you have no ideas,
but you definitely need as much text as possible about yourself and your music
so that when someone comes to the site, they have something to do there, not just an mp3 player.
Also uses images, etc.