giscus.json should be placed in the root of the repository whose Discussions is used for giscus. It doesn't need to be hosted on your website, so it's not in /content or /static.

It's used to control how giscus can interact with your repository. If you think about it, you can know that it doesn't make sense to let your website host it.

Yes, I see, I should put this file in the root of the github repository where discussions work, I really appreciate your reply, it has been bothering me for a long time!