This issue has been reported earlier as a part of CARGO-1278.
The target parameter for RemoteDeployer is required to allow deploy to non-clustered instances. In such a case the domain administration port is not enough because there's no way to address a single instance among others.
It could look like <cargo.glassfish.target>myinstance</cargo.glassfish.target>.
Sure I can use InstalledLocalDeployer or asadmin directly, but this brings many inconveniences like having a GF installation and set up build scripts everywhere I'd like to deploy from.