According to the general instruction to the github.com API and the explanation of the create command
curl -u "krichter722" https://api.github.com # works (returns JSON response)
curl -d '{"name":"test"}' https://api.github.com/user/repos/
should work and create a repository, but the second command fails with
{
"message": "Not Found",
"documentation_url": "https://developer.github.com/v3"
}
I found Using `curl` to create a repo on GitHub.com with two-factor authentication which resolves an issue caused by missing parts in the request for two-factor authentication.
Other questions, like "Bad Credentials" when attempting to create a GitHub repo through the CLI using curl, indicate that the URL is correct (the creation fails due to bad credentials according to error message in this case).