The following rules apply to secret names:

- Secret names can only contain alphanumeric characters (`[a-z]`, `[A-Z]`, `[0-9]`) or underscores (`_`). Spaces are not allowed.
- Secret names must not start with the `GITHUB_` prefix.
- Secret names must not start with a number.
- Secret names are not case-sensitive.
- Secret names must be unique at the level they are created at.