diff --git a/__tests__/ain.test.ts b/__tests__/ain.test.ts
index b7e7a0d..f586760 100644
--- a/__tests__/ain.test.ts
+++ b/__tests__/ain.test.ts
@@ -549,16 +549,44 @@ describe('ain-js', function() {
       expect(txCount).not.toBeNull();
     });
 
-    it('getProposer', async function () {
-      const proposer = await ain.getProposer(1);
-      const hash = (await ain.getBlockByNumber(1)).hash || "";
-      expect(await ain.getProposer(hash)).toBe(proposer);
+    it('getValidatorInfo', async function () {
+      const lastBlock = await ain.getLastBlock();
+      expect(lastBlock).not.toBeNull();
+      expect(lastBlock.proposer).not.toBeNull();
+      const info = await ain.getValidatorInfo(lastBlock.proposer);
+      expect(info).not.toBeNull();
+    });
+
+    it('getValidatorsByNumber', async function () {
+      const lastBlock = await ain.getLastBlock();
+      expect(lastBlock).not.toBeNull();
+      expect(lastBlock.number).not.toBeNull();
+      const validators = await ain.getValidatorsByNumber(lastBlock.number);
+      expect(validators).toStrictEqual(lastBlock.validators);
+    });
+
+    it('getValidatorsByHash', async function () {
+      const lastBlock = await ain.getLastBlock();
+      expect(lastBlock).not.toBeNull();
+      expect(lastBlock.number).not.toBeNull();
+      const validators = await ain.getValidatorsByHash(lastBlock.hash);
+      expect(validators).toStrictEqual(lastBlock.validators);
+    });
+
+    it('getProposerByNumber', async function () {
+      const lastBlock = await ain.getLastBlock();
+      expect(lastBlock).not.toBeNull();
+      expect(lastBlock.number).not.toBeNull();
+      const proposer = await ain.getProposerByNumber(lastBlock.number);
+      expect(proposer).toBe(lastBlock.proposer);
     });
 
-    it('getValidators', async function () {
-      const validators = await ain.getValidators(4);
-      const hash = (await ain.getBlockByNumber(4)).hash || "";
-      expect(await ain.getValidators(hash)).toStrictEqual(validators);
+    it('getProposerByHash', async function () {
+      const lastBlock = await ain.getLastBlock();
+      expect(lastBlock).not.toBeNull();
+      expect(lastBlock.hash).not.toBeNull();
+      const proposer = await ain.getProposerByHash(lastBlock.hash);
+      expect(proposer).toBe(lastBlock.proposer);
     });
 
     // TODO(liayoo): add getTransactionResult method and test case for it.
diff --git a/src/ain.ts b/src/ain.ts
index 36f5bc8..49c4411 100755
--- a/src/ain.ts
+++ b/src/ain.ts
@@ -165,27 +165,48 @@ export default class Ain {
   }
 
   /**
-   * Fetches the forger's address of a block with a block hash or block number.
-   * @param {string | number} blockHashOrBlockNumber The block hash or block number.
+   * Fetches the information of the given validator address.
+   * @param {string} address The validator address.
+   * @returns {Promise<any>}
+   */
+  getValidatorInfo(address: string): Promise<any> {
+    return this.provider.send('ain_getValidatorInfo', { address });
+  }
+
+  /**
+   * Fetches the validator list of a block with a block number.
+   * @param {number} blockNumber The block number.
+   * @returns {Promise<any>}
+   */
+  getValidatorsByNumber(blockNumber: number): Promise<any> {
+    return this.provider.send('ain_getValidatorsByNumber', { number: blockNumber });
+  }
+
+  /**
+   * Fetches the validator list of a block with a block hash.
+   * @param {string} blockHash The block hash.
+   * @returns {Promise<any>}
+   */
+  getValidatorsByHash(blockHash: string): Promise<any> {
+    return this.provider.send('ain_getValidatorsByHash', { hash: blockHash });
+  }
+
+  /**
+   * Fetches the block proproser's address of a block with a block number.
+   * @param {number} blockNumber The block number.
    * @returns {Promise<string>}
    */
-  getProposer(blockHashOrBlockNumber: string | number): Promise<string> {
-    const byHash = typeof blockHashOrBlockNumber === 'string'
-    const rpcMethod = byHash ? 'ain_getProposerByHash' : 'ain_getProposerByNumber';
-    return this.provider.send(rpcMethod,
-        {[byHash ? 'hash' : 'number']: blockHashOrBlockNumber});
+  getProposerByNumber(blockNumber: number): Promise<string> {
+    return this.provider.send('ain_getProposerByNumber', { number: blockNumber });
   }
 
   /**
-   * Fetches the validator list of a block with a block hash or block number.
-   * @param {string | number} blockHashOrBlockNumber The block hash or block number.
-   * @returns {Promise<string[]>}
+   * Fetches the block proproser's address of a block with a block hash.
+   * @param {string} blockHash The block hash.
+   * @returns {Promise<string>}
    */
-  getValidators(blockHashOrBlockNumber: string | number): Promise<string[]> {
-    const byHash = typeof blockHashOrBlockNumber === 'string'
-    const rpcMethod = byHash ? 'ain_getValidatorsByHash' : 'ain_getValidatorsByNumber';
-    return this.provider.send(rpcMethod,
-        {[byHash ? 'hash' : 'number']: blockHashOrBlockNumber});
+  getProposerByHash(blockHash: string): Promise<string> {
+    return this.provider.send('ain_getProposerByHash', { hash: blockHash });
   }
 
   /**