How to add readable name and description to templates?

Question

To add a readable title to a template, we can add the following to theme.json

"customTemplates": [
        {
            "name": "single-post-type-name",
            "title": "Single Post Type Name"
        },
 ...

But as Will mentioned in the comments, it is not possible to add descriptions yet. There is an issue to track it here: https://github.com/WordPress/gutenberg/issues/44097