diff --git a/types/chrome/index.d.ts b/types/chrome/index.d.ts
index 9946c79c38..69abf9896d 100644
--- a/types/chrome/index.d.ts
+++ b/types/chrome/index.d.ts
@@ -2316,9 +2316,11 @@ declare namespace chrome.enterprise.deviceAttributes {
     /**
      * @description Fetches the value of the device identifier of the directory API, that is generated by the server and identifies the cloud record of the device for querying in the cloud directory API.
      * @export
-     * @param {(deviceId) => void} callback Called with the device identifier of the directory API when received.
+     * @param callback Called with the device identifier of the directory API when received.
+     * The callback parameter should be a function that looks like this:
+     * function(string deviceId) {...};
      */
-    export function getDirectoryDeviceId(callback: (deviceId) => void): void;
+    export function getDirectoryDeviceId(callback: (deviceId: string) => void): void;
 }
 
 ////////////////////