User Registration problems via JSON

I want to be able to register users through the solid server api via the /api/accounts/new endpoint. Using python I could do the following:

import requests

data = {
    'email': '...valid email',
    'username': '...valid username',
    'name': '...valid name',
    'password': '...valid password'
}
url = 'https://mysolidserver.com/api/accounts/new'
response = requests.post(url, data=data)
print(response.status_code) # which is 401

I am given a status code of 401 since I'm redirected to the username.mysolidserver.com page. This is awkward API UX since I'm expecting a confirmation response, probably in JSON with a status code in the 200's. Moreover, if I set headers={'Content-Type': 'application/json'} in the request, I am given an error claiming that the username is not valid.

Fortunately if the registration doesn't work, I'm given a status code of 400, so I can use this fact right now in my app.

Start by reproducing POST requests to /api/accounts/new with form data and application/json, checking redirects, status codes, and response bodies. The change is done when valid registrations receive a useful JSON success response with a 2xx status and invalid registrations continue to return an appropriate error response.