how to config remotefs.remote."host" to work with ssh-agent service authentication prodiver ?

[manufv]

hello,
This is a 'how-to' request.
working on windows with openSSH correctly set, I'll use remotefs.remote config associated with a ssh-agent service.

ssh-agent is well configured and keys are loaded, at shell I can use 'ssh user@hostname' and ssh agent provide authentication correctly.

With remotefs.remote, I do not understand how to configure to not provide my passphrase in the settings !

I'll appreciate any help.
With kind regards

I suppose ... but it does not works :

"remotefs.remote": {
        "myhost": {
            "scheme":"sftp",
            "host": "myhostfullname",
            "username": "myuserid",
            "rootPath": "/home/myuserid",
            "agent": "pageant"
}