Currently, it appears that you can't change an avatar (or world's) name or description after uploading. Your only recourse appears to be completely re-uploading the item.

Names and descriptions should be edit-able after upload from the VRChat Conter ("Manage Uploaded Content"). Please make this so.

It would be nice if we could also upload whatever image we want for the screenshot, so long as it's within certain size limits. Think of it like YouTube's thumbnail system - you CAN just take a shot from the content directly, or you can upload a custom thumbnail. It'll elimintate the process of needing to bring images into Unity for people who want to use a custom image.

Point being - I think object metadata should be edit-able by the author at any time. Please consider making that so.

Thank you.