Token Filte Module:

Install and enable Token Filter module and enable 'Replace tokens' filter e.g. for Full HTML text format.

For testing may edit any node and just type [site:name] to see if that works.

For Help, as admin go to Help->Token and you will find all the tokens you can use (/admin/help/token).

Custom filter 模块也挺好，自定义替换内容，可以参考一下。