{
    "additionalProperties": false,
    "description": "A join_group GTM server-side event.",
    "properties": {
        "group_id": {
            "description": "The ID of the group.",
            "maxLength": 4096,
            "type": [
                "string",
                "null"
            ]
        }
    },
    "self": {
        "format": "jsonschema",
        "name": "join_group",
        "vendor": "com.google.tag-manager.server-side",
        "version": "1-0-0"
    },
    "type": "object"
}