Method doesn't allow unregistered callers (callers without established identity)

[rino1]

I would like to get the list of RSS feeds relating to my enrollments on YouTube.

I tried like this

$ curl https://www.googleapis.com/youtube/v3/subscriptions?forMine=true&key=XXX
{
  "error": {
    "code": 403,
    "message": "Method doesn't allow unregistered callers (callers without established identity). Please use API Key or other form of API consumer identity to call this API.",
    "errors": [
      {
        "message": "Method doesn't allow unregistered callers (callers without established identity). Please use API Key or other form of API consumer identity to call this API.",
        "domain": "global",
        "reason": "forbidden"
      }
    ],
    "status": "PERMISSION_DENIED"
  }
}

but as you see it doesn't work.

Why?

[Benjamin-Loison]

Your issue does not seem YouTube operational API related despite being related to own official instance seldom issue referenced at #237.

If you want help about your issue raise a question on Stack Overflow.