How long valid download_url with token in private repo


I have a question about download_url in my private repo.

I tried to get download_url of an image file (<1MB) using Contents API v3.

GET /repos/{owner}/{repo}/contents/{path}


$ hub api repos/${private_repo}/contents/${path_to_file} | \
  jq -r .download_url


This API works well and I can access it without any authentication because download_url involves token=****.

But I found I can’t access with same url after 10 minutes, so I guess token has expired.

Can you explain the expiry of download_url in private repo?

Related question

I found similar question about download_url with authentication token in private repo.

The token will expire in 7 days.

According to these tickets, token may be valid in 7 days, but in my side the token has expired within 10 minutes.

What is difference of the expiration date of token?