lib/alertV2/AlertV2.js
function (identifier, data, config, cb) {
            if (data.keys === undefined) {
                return new Error("details param can not be empty.");
            }
            var path = api.getPathWithData(baseURL, identifier, detailsActionPath, data);
            api.delete(path, config, cb);
        }
function (identifier, data, config, cb) {
            if (data.keys === undefined) {
                return new Error("details param can not be empty.");
            }
            var path = api.getPathWithData(baseURL, identifier, detailsActionPath, data);
            api.delete(path, config, cb);
        }
This request is to remove details(custom properties) using their keys from an alert in Opsgenie.

One of id, tinyId or alias parameters should be specified with remove details request as identifier.
Alias option can only be used for open alerts
example identifier objects:
{identifier : "123", identifierType : "tiny"}
{identifier : "123-23-123", identifierType : "id"}
{identifier : "alertAlias", identifierType : "alias"}

Also, details param is mandatory for this request. This param should provide keys to remove as a comma separated string.
Example details params:
details : "key1, key2"