Authorization required: sitemap.xml
Verification word: unvented

Approve on your phone -- open or scan this on a device with your passkey:
  https://auth.ck1.me/a/eyJhbGciOiJIUzI1NiJ9.eyJyZXMiOnsidHlwZSI6Im9iamVjdCIsImlkIjoic2l0ZW1hcC54bWwifSwid29yZCI6InVudmVudGVkIiwianRpIjoiM2RhM2I1MjcyZDQ4NGNmZTk4N2I0M2MyZTIxN2Q3MTMiLCJpc3MiOiJzZXJ2ZXMuY2sxLm1lIiwiYXVkIjoiYXV0aC5jazEubWUiLCJpYXQiOjE3ODMxMDc2MDAsImV4cCI6MTc4MzEwNzkwMH0.cfgdNLNKAeQxwfPU8_MtAHJCzfPhqPs8cqOZIj_4DeY

(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.eyJyZXMiOnsidHlwZSI6Im9iamVjdCIsImlkIjoic2l0ZW1hcC54bWwifSwid29yZCI6InVudmVudGVkIiwianRpIjoiM2RhM2I1MjcyZDQ4NGNmZTk4N2I0M2MyZTIxN2Q3MTMiLCJpc3MiOiJzZXJ2ZXMuY2sxLm1lIiwiYXVkIjoiYXV0aC5jazEubWUiLCJpYXQiOjE3ODMxMDc2MDAsImV4cCI6MTc4MzEwNzkwMH0.cfgdNLNKAeQxwfPU8_MtAHJCzfPhqPs8cqOZIj_4DeY' -o 'sitemap.xml'