Curl fails on sftp password authentication

Question

When I manually sftp using username and password it works fine, when using curl it fails. The same script will successfully connect to other servers with no problem. Because

Answer 1

thanks and for publickey authentication :

curl -v -k --pubkey ~/.ssh/id_rsa.pub sftp://username@host/

Answer 2

Got it working, turned out to be pretty simple but would only work with the username and password in the url.

curl -v --insecure sftp://username:urlencodedPassword@somedomain.com

This would not work.

curl -v --insecure --user username:urlencodedPassword sftp://somedomain.com

Someone who knows more than me could probably elaborate as to why they 2nd one wouldn't work.