Webhook-url-http-3a-2f-2f169.254.169.254-2fmetadata-2fidentity-2foauth2-2ftoken _best_ -

http://169.254.169.254/* http://%31%36%39%2e%32%35%34%2e%31%36%39%2e%32%35%34/* *metadata/identity/oauth2/token*

The service does:

http://169.254.169.254/metadata/identity/oauth2/token http://169