How to send data to hosted graphite service

How can we send information to hosted metrics without using carbon relay?

The docs just say:

This is the URL you use to send the data to us.

So how do I pass in authorization? Do I need to put my subdomain in anywhere?

You are right that is not well documented on the metrics page.

Here are some examples:

That curl example might be incorrect. I got it to work with the -u flag instead of the authorization header. 6515 is the id of my hosted graphite instance and you can find it on your metrics page on in the Grafana Data Source settings section:

curl -XPOST -u "6515:myAPIKey" -H "Content-Type: application/json" -d '[{
    "name": "test.metric",
    "interval": 10,
    "value": 12.345,
    "time": 1534685580