$ maas andreas-vmwarestack devices list
Success.
Machine-readable output follows:
[
    {
        "macaddress_set": [
            {
                "mac_address": "00:16:3e:a9:76:e4"
            }
        ], 
        "zone": {
            "resource_uri": "/MAAS/api/1.0/zones/default/", 
            "name": "default", 
            "description": ""
        }, 
        "parent": "node-5af81cf4-9399-11e5-a306-00505698101c", 
        "ip_addresses": [], 
        "hostname": "juju-machine-0-lxc-0.vmwarestack", 
        "system_id": "node-93aa1ff4-939c-11e5-b4f2-00505698101c", 
        "owner": "andreas", 
        "tag_names": [], 
        "resource_uri": "/MAAS/api/1.0/devices/node-93aa1ff4-939c-11e5-b4f2-00505698101c/"
    }, 
    {
        "macaddress_set": [
            {
                "mac_address": "00:16:3e:cf:46:20"
            }
        ], 
        "zone": {
            "resource_uri": "/MAAS/api/1.0/zones/default/", 
            "name": "default", 
            "description": ""
        }, 
        "parent": "node-5af81cf4-9399-11e5-a306-00505698101c", 
        "ip_addresses": [], 
        "hostname": "juju-machine-0-lxc-1.vmwarestack", 
        "system_id": "node-c9ca3b40-939d-11e5-b0d1-00505698101c", 
        "owner": "andreas", 
        "tag_names": [], 
        "resource_uri": "/MAAS/api/1.0/devices/node-c9ca3b40-939d-11e5-b0d1-00505698101c/"
    }
]