Authorization required: sitemap.xml
Verification word: spherical

Approve on your phone -- open or scan this on a device with your passkey:
  https://auth.ck1.me/a/eyJhbGciOiJIUzI1NiJ9.eyJyZXMiOnsidHlwZSI6Im9iamVjdCIsImlkIjoic2l0ZW1hcC54bWwifSwid29yZCI6InNwaGVyaWNhbCIsImp0aSI6IjUxNGM2OTllOTZjNjQ4MDBiMGE2MTM2MTJlZmY5Y2VjIiwiaXNzIjoic2VydmVzLmNrMS5tZSIsImF1ZCI6ImF1dGguY2sxLm1lIiwiaWF0IjoxNzkzMTQ0Nzk4LCJleHAiOjE3OTMxNDUwOTh9.VCKh3LJG1c8RM9GQo0P_9qTN-7pDLSjP-nOZtOmy5r0

(No browser on this box? Cmd-click that link to open it on your laptop;
 it shows a QR you can scan with your phone.)

Then fetch the file -- this command waits until you approve:
  curl -fL 'https://serves.ck1.me/sitemap.xml?grant=eyJhbGciOiJIUzI1NiJ9.eyJyZXMiOnsidHlwZSI6Im9iamVjdCIsImlkIjoic2l0ZW1hcC54bWwifSwid29yZCI6InNwaGVyaWNhbCIsImp0aSI6IjUxNGM2OTllOTZjNjQ4MDBiMGE2MTM2MTJlZmY5Y2VjIiwiaXNzIjoic2VydmVzLmNrMS5tZSIsImF1ZCI6ImF1dGguY2sxLm1lIiwiaWF0IjoxNzkzMTQ0Nzk4LCJleHAiOjE3OTMxNDUwOTh9.VCKh3LJG1c8RM9GQo0P_9qTN-7pDLSjP-nOZtOmy5r0' -o 'sitemap.xml'