diff --git a/api/@ohos.worker.d.ts b/api/@ohos.worker.d.ts
index d7b9ca850a7137eced524b40a7a5231cb4e684c7..1ae39b267c033e7dd0e8d0f5e5e1bf35743026e7 100644
--- a/api/@ohos.worker.d.ts
+++ b/api/@ohos.worker.d.ts
@@ -13,104 +13,364 @@
  * limitations under the License.
  */
 
+/**
+* Provides options that can be set for the worker to create.
+* @devices phone, tablet, wearable
+* @since 7
+*/
 export interface WorkerOptions {
+  /**
+   * Mode in which the worker executes the script.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   type?: "classic" | "module";
+
+  /**
+   * Name of the worker.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   name?: string;
+
+  /**
+   * Whether the worker is shared.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   shared?: boolean;
 }
 
+/**
+ * Defines the event.
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 export interface Event {
+  /**
+   * Type of the Event.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly type: string;
+
+  /**
+   * Timestamp(accurate to millisecond) when the event is created.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly timeStamp: number;
 }
 
+/**
+ * Provides detailed information about the exception occurred during worker execution.
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 interface ErrorEvent extends Event {
+  /**
+   * Information about the exception.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly message: string;
+
+  /**
+   * File where the exception is located.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly filename: string;
+
+  /**
+   * Number of the line where the exception is located.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly lineno: number;
+
+  /**
+   * Number of the column where the exception is located.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly colno: number;
+
+  /**
+   * Type of the exception.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly error: Object;
 }
 
+/**
+ * Holds the data transferred between worker threads.
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 declare interface MessageEvent<T = Object> extends Event {
-  // the data of the message.
+  /**
+   * Data transferred when an exception occurs.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly data: T;
 }
 
+/**
+ * Specifies the object whose ownership need to be transferred during data transfer.
+ * The object must be ArrayBuffer.
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 export interface PostMessageOptions {
+  /**
+   * ArrayBuffer array used to transfer the ownership.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   transfer?: Object[];
 }
 
+/**
+ * Implements evemt listening.
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 export interface EventListener {
-    (evt: Event): void | Promise<void>;
+  /**
+   * Specifies the callback to invoke.
+   * @param evt Event class for the callback to invoke.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
+  (evt: Event): void | Promise<void>;
 }
 
+/**
+ * Type of message, only "message" and "messageerror".
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 type MessageType = "message" | "messageerror";
 
+/**
+ * Specific event features.
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 declare interface EventTarget {
+  /**
+   * Adds an event listener to the worker.
+   * @param type  Type of the event to listen for.
+   * @param listener Callback to invoke when an event of the specified type occurs.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   addEventListener(
     type: string,
     listener: EventListener
   ): void;
 
+  /**
+   * Dispatches the event defined for the worker.
+   * @param event Event to dispatch.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   dispatchEvent(event: Event): boolean;
 
+  /**
+   * Removes an event defined for the worker.
+   * @param type Type of the event for which the event listener is removed.
+   * @param callback Callback of the event listener to remove.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   removeEventListener(
     type: string,
     callback?: EventListener
   ): void;
 
+  /**
+   * Removes all event listeners for the worker.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   removeAllListener(): void;
 }
 
-/* woker sider interface */
+/**
+ * Specifies the worker thread running environment, which is isolated from the host thread environment.
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 declare interface WorkerGlobalScope extends EventTarget {
-  // worker name.
+  /**
+   * Worker name specified when there is a new worker.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   readonly name: string;
 
+  /**
+   * The onerror attribute of parentPort specifies
+   * the event handler to be called when an exception occurs during worker execution.
+   * The event handler is executed in the worker thread.
+   * @param ev Error data.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   onerror?: (ev: ErrorEvent) => void;
-  onoffline?: (ev: Event) => void;
-  ononline?: (ev: Event) => void;
-
   readonly self: WorkerGlobalScope & typeof globalThis;
 }
 
+/**
+ * Specifies the worker thread running environment, which is isolated from the host thread environment
+ * @devices phone, tablet, wearable
+ * @since 7
+ */
 declare interface DedicatedWorkerGlobalScope extends WorkerGlobalScope {
+  /**
+   * The onmessage attribute of parentPort specifies the event handler
+   * to be called then the worker thread receives a message sent by
+   * the host thread through worker postMessage.
+   * The event handler is executed in the worker thread.
+   * @param ev Message received.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   onmessage?: (this: DedicatedWorkerGlobalScope, ev: MessageEvent) => void;
+
+  /**
+   * The onmessage attribute of parentPort specifies the event handler
+   * to be called then the worker receives a message that cannot be deserialized.
+   * The event handler is executed in the worker thread.
+   * @param ev Error data.
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   onmessageerror?: (this: DedicatedWorkerGlobalScope, ev: MessageEvent) => void;
 
+  /**
+   * Close the worker thread to stop the worker from receiving messages
+   * @devices phone, tablet, wearable
+   * @since 7
+   */
   close(): void;
+
   /**
-   * Clones message and transmits it to the Worker object associated with dedicatedWorkerGlobal.
-   * transfer can be passed as a list of objects that are to be transferred rather than cloned.
+   * Send a message to be host thread from the worker
+   * @param messageObject Data to be sent to the worker
+   * @param transfer array cannot contain null.
+   * @devices phone, tablet, wearable
+   * @since 7
    */
   postMessage(messageObject: Object, transfer: Transferable[]): void;
   postMessage(messageObject: Object, options?: PostMessageOptions): void;
 }
 
 /**
- * @devices phone, tablet
+ * JS cross-thread communication tool
+ * @devices phone, tablet, wearable
+ * @since 7
  */
 declare namespace worker {
   class Worker extends EventTarget {
-      constructor(scriptURL: string, options?: WorkerOptions);
-      onexit?: (code: number) => void;
-      // error callback.
-      onerror?: (err: ErrorEvent) => void;
-      // type = "message".
-      onmessage?: (event: MessageEvent) => void;
-      onmessageerror?: (event: MessageEvent) => void;
-      // use structured clone algorithm to transfor object.
-      postMessage(message: Object, transfer: ArrayBuffer[]): void;
-      // support transfor list type:
-      // all primitive types, Boolean, String, Date, RegExp, Map, Set, Array, Object(can represet literal).
-      postMessage(message: Object, options?: PostMessageOptions): void;
-
-      on(type: string, listener: EventListener): void;
-      once(type: string, listener: EventListener): void;
-      off(type: string, listener?: EventListener): void;
-
-      terminate(): void;
+    /**
+     * Creates a worker instance
+     * @param scriptURL URL of the script to be executed by the worker
+     * @param options Options that can be set for the worker
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    constructor(scriptURL: string, options?: WorkerOptions);
+
+    /**
+     * The onexit attribute of the worker specifies the event handler to be called
+     * when the worker exits. The handler is executed in the host thread.
+     * @param code Code indicating the worker exit state
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    onexit?: (code: number) => void;
+
+    /**
+     * The onerror attribute of the worker specifies the event handler to be called
+     * when an exception occurs during worker execution.
+     * The event handler is executed in the host thread.
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    onerror?: (err: ErrorEvent) => void;
+
+    /**
+     * The onmessage attribute of the worker specifies the event handler
+     * to be called then the host thread receives a message created by itself
+     * and sent by the worker through the parentPort.postMessage.
+     * The event handler is executed in the host thread.
+     * @param event Message received.
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    onmessage?: (event: MessageEvent) => void;
+
+    /**
+     * The onmessage attribute of the worker specifies the event handler
+     * when the worker receives a message that cannot be serialized.
+     * The event handler is executed in the host thread.
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    onmessageerror?: (event: MessageEvent) => void;
+
+    /**
+     * Sends a message to the worker thread.
+     * The data is transferred using the structured clone algorithm.
+     * @param message Data to be sent to the worker
+     * @param transfer ArrayBuffer instance that can be transferred.
+     * The transferList array cannot contain null.
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    postMessage(message: Object, transfer: ArrayBuffer[]): void;
+    postMessage(message: Object, options?: PostMessageOptions): void;
+
+    /**
+     * Adds an event listener to the worker.
+     * @param type Adds an event listener to the worker.
+     * @param listener Callback to invoke when an event of the specified type occurs.
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    on(type: string, listener: EventListener): void;
+
+    /**
+     * Adds an event listener to the worker
+     * and removes the event listener automically after it is invoked once.
+     * @param type Type of the event to listen for
+     * @param listener Callback to invoke when an event of the specified type occurs
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    once(type: string, listener: EventListener): void;
+
+    /**
+     * Removes an event listener to the worker.
+     * @param type Type of the event for which the event listener is removed.
+     * @param listener Callback of the event listener to remove.
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    off(type: string, listener?: EventListener): void;
+
+    /**
+     * Terminates the worker thread to stop the worker from receiving messages
+     * @devices phone, tablet, wearable
+     * @since 7
+     */
+    terminate(): void;
   }
   const parentPort: DedicatedWorkerGlobalScope;
 }