gistfile1.txt

{
    "clauses": [
        {
            "field": "/data/entities/mentions/*/id", 
            "object_type": "message", 
            "operator": "one_of", 
            "value": "$authorized_userids"
        }, 
        {
            "field": "/meta/channel_type", 
            "object_type": "message", 
            "operator": "one_of", 
            "value": [
                "net.patter-app.room"
            ]
        }
    ], 
    "match_policy": "include_all",
    "name": "patter_mentions"
}