diff --git a/package.json b/package.json
index 4a94c80..cd25015 100644
--- a/package.json
+++ b/package.json
@@ -36,6 +36,7 @@
     "@types/node-fetch": "^2.5.4",
     "@types/qs": "^6.9.5",
     "@types/url-safe-base64": "^1.1.0",
+    "@types/uuid": "^8.3.0",
     "@typescript-eslint/eslint-plugin": "^4.5.0",
     "@typescript-eslint/parser": "^4.5.0",
     "conventional-changelog-cli": "^2.1.0",
diff --git a/src/__tests__/index.test.ts b/src/__tests__/index.test.ts
index 8950c26..170bd66 100644
--- a/src/__tests__/index.test.ts
+++ b/src/__tests__/index.test.ts
@@ -28,7 +28,6 @@ describe('index', () => {
     const options = instance.storedOptions;
     const storedOptions = {
       clientId: options.clientId,
-      codeVerifier: options.codeVerifier,
       mode: options.mode,
       redirectUri: options.redirectUri,
       state: options.state,
@@ -81,12 +80,10 @@ describe('index', () => {
     mtLinkSdk.init('clientId', {
       mode: 'local',
       state: 'state',
-      codeVerifier: 'codeVerifier',
     });
 
     expect(mtLinkSdk.storedOptions.mode).toBe('local');
     expect(mtLinkSdk.storedOptions.state).toBe('state');
-    expect(mtLinkSdk.storedOptions.codeVerifier).toBe('codeVerifier');
   });
 
   test('invalid mode default to production', () => {
diff --git a/src/api/__tests__/authorize.test.ts b/src/api/__tests__/authorize.test.ts
index 44c2a39..39d3867 100644
--- a/src/api/__tests__/authorize.test.ts
+++ b/src/api/__tests__/authorize.test.ts
@@ -39,7 +39,6 @@ describe('api', () => {
       mockedStorage.set.mockClear();
       open.mockClear();
 
-      const codeVerifier = 'codeVerifier';
       const country = 'JP';
       const scopes = 'points_read';
       const cobrandClientId = 'cobrandClientId';
@@ -48,7 +47,6 @@ describe('api', () => {
       const mtLinkSdk = new MtLinkSdk();
       mtLinkSdk.init(clientId, {
         redirectUri,
-        codeVerifier,
         country,
         scopes,
         locale,
@@ -65,24 +63,18 @@ describe('api', () => {
         response_type: 'code',
         scope: scopes,
         redirect_uri: redirectUri,
-        code_challenge: 'N1E4yRMD7xixn_oFyO_W3htYN3rY7-HMDKJe6z6r928',
-        code_challenge_method: 'S256',
         country,
         locale,
         configs: generateConfigs(),
       });
       const url = `${MY_ACCOUNT_DOMAINS.production}/oauth/authorize?${query}`;
       expect(open).toBeCalledWith(url, '_self');
-
-      expect(mockedStorage.set).toBeCalledTimes(1);
-      expect(mockedStorage.set).toBeCalledWith('codeVerifier', codeVerifier);
     });
 
     test('with options', () => {
       mockedStorage.set.mockClear();
       open.mockClear();
 
-      const codeVerifier = 'codeVerifier';
       const state = 'state';
       const country = 'JP';
       const scopes = 'points_read';
@@ -92,7 +84,6 @@ describe('api', () => {
 
       authorize(mtLinkSdk.storedOptions, {
         state,
-        codeVerifier,
         redirectUri,
         country,
         scopes,
@@ -105,17 +96,12 @@ describe('api', () => {
         response_type: 'code',
         scope: scopes,
         redirect_uri: redirectUri,
-        code_challenge: 'N1E4yRMD7xixn_oFyO_W3htYN3rY7-HMDKJe6z6r928',
-        code_challenge_method: 'S256',
         state,
         country,
         configs: generateConfigs(),
       });
       const url = `${MY_ACCOUNT_DOMAINS.production}/oauth/authorize?${query}`;
       expect(open).toBeCalledWith(url, '_self');
-
-      expect(mockedStorage.set).toBeCalledTimes(2);
-      expect(mockedStorage.set).toBeCalledWith('codeVerifier', codeVerifier);
     });
 
     test('without window', () => {
diff --git a/src/api/__tests__/onboard.test.ts b/src/api/__tests__/onboard.test.ts
index e46efe9..24e471b 100644
--- a/src/api/__tests__/onboard.test.ts
+++ b/src/api/__tests__/onboard.test.ts
@@ -67,7 +67,6 @@ describe('api', () => {
       mockedStorage.set.mockClear();
       open.mockClear();
 
-      const codeVerifier = 'codeVerifier';
       const country = 'JP';
       const scopes = 'points_read';
       const cobrandClientId = 'cobrandClientId';
@@ -76,7 +75,6 @@ describe('api', () => {
       const mtLinkSdk = new MtLinkSdk();
       mtLinkSdk.init(clientId, {
         redirectUri,
-        codeVerifier,
         country,
         scopes,
         email,
@@ -94,24 +92,18 @@ describe('api', () => {
         response_type: 'code',
         scope: scopes,
         redirect_uri: redirectUri,
-        code_challenge: 'N1E4yRMD7xixn_oFyO_W3htYN3rY7-HMDKJe6z6r928',
-        code_challenge_method: 'S256',
         country,
         locale,
         configs: generateConfigs({ email }),
       });
       const url = `${MY_ACCOUNT_DOMAINS.production}/onboard?${query}`;
       expect(open).toBeCalledWith(url, '_self');
-
-      expect(mockedStorage.set).toBeCalledTimes(1);
-      expect(mockedStorage.set).toBeCalledWith('codeVerifier', codeVerifier);
     });
 
     test('with options', () => {
       mockedStorage.set.mockClear();
       open.mockClear();
 
-      const codeVerifier = 'codeVerifier';
       const state = 'state';
       const country = 'JP';
       const scopes = 'points_read';
@@ -121,7 +113,6 @@ describe('api', () => {
 
       onboard(mtLinkSdk.storedOptions, {
         state,
-        codeVerifier,
         redirectUri,
         country,
         scopes,
@@ -135,17 +126,12 @@ describe('api', () => {
         response_type: 'code',
         scope: scopes,
         redirect_uri: redirectUri,
-        code_challenge: 'N1E4yRMD7xixn_oFyO_W3htYN3rY7-HMDKJe6z6r928',
-        code_challenge_method: 'S256',
         state,
         country,
         configs: generateConfigs({ email }),
       });
       const url = `${MY_ACCOUNT_DOMAINS.production}/onboard?${query}`;
       expect(open).toBeCalledWith(url, '_self');
-
-      expect(mockedStorage.set).toBeCalledTimes(2);
-      expect(mockedStorage.set).toBeCalledWith('codeVerifier', codeVerifier);
     });
 
     test('without window', () => {
diff --git a/src/api/__tests__/token-info.test.ts b/src/api/__tests__/token-info.test.ts
index becd165..35b53a8 100644
--- a/src/api/__tests__/token-info.test.ts
+++ b/src/api/__tests__/token-info.test.ts
@@ -1,7 +1,9 @@
 import fetch from 'jest-fetch-mock';
+import qs from 'qs';
 
 import { MY_ACCOUNT_DOMAINS } from '../../server-paths';
 import { MtLinkSdk } from '../..';
+import { generateConfigs } from '../../helper';
 import tokenInfo from '../token-info';
 
 describe('api', () => {
@@ -39,15 +41,19 @@ describe('api', () => {
       fetch.mockResponseOnce(JSON.stringify(response));
 
       await tokenInfo(mtLinkSdk.storedOptions, token);
+      const query = qs.stringify({
+        client_id: clientId,
+        configs: generateConfigs(),
+      });
 
-      const url = `${MY_ACCOUNT_DOMAINS.production}/oauth/token/info.json`;
+      const url = `${MY_ACCOUNT_DOMAINS.production}/oauth/token/info.json?${query}`;
 
       expect(fetch).toBeCalledTimes(1);
       expect(fetch).toBeCalledWith(url, {
         method: 'GET',
         headers: {
           Authorization: `Bearer ${token}`,
-          'x-api-key': clientId,
+          'API-Version': '1604911588',
         },
       });
     });
diff --git a/src/api/authorize.ts b/src/api/authorize.ts
index 6589d45..361506c 100644
--- a/src/api/authorize.ts
+++ b/src/api/authorize.ts
@@ -11,7 +11,10 @@ import { MY_ACCOUNT_DOMAINS } from '../server-paths';
 import { StoredOptions, AuthorizeOptions } from '../typings';
 import storage from '../storage';
 
-export default function authorize(storedOptions: StoredOptions, options: AuthorizeOptions = {}): void {
+export default function authorize(
+  storedOptions: StoredOptions,
+  options: AuthorizeOptions = {}
+): void {
   if (!window) {
     throw new Error('[mt-link-sdk] `authorize` only works in the browser.');
   }
diff --git a/src/api/exchange-token.ts b/src/api/exchange-token.ts
index fd19730..218defa 100644
--- a/src/api/exchange-token.ts
+++ b/src/api/exchange-token.ts
@@ -21,21 +21,13 @@ export default async function exchangeToken(
   storedOptions: StoredOptions,
   options: ExchangeTokenOptions = {}
 ): Promise<string> {
-  const {
-    clientId,
-    redirectUri: defaultRedirectUri,
-    mode
-  } = storedOptions;
+  const { clientId, redirectUri: defaultRedirectUri, mode } = storedOptions;
 
   if (!clientId) {
     throw new Error('[mt-link-sdk] Make sure to call `init` before calling `exchangeToken`.');
   }
 
-  const {
-    redirectUri = defaultRedirectUri,
-    code = getCode(),
-    codeVerifier,
-  } = options;
+  const { redirectUri = defaultRedirectUri, code = getCode(), codeVerifier } = options;
 
   if (!code) {
     throw new Error(
diff --git a/src/api/token-info.ts b/src/api/token-info.ts
index 0410fb6..f0a1675 100644
--- a/src/api/token-info.ts
+++ b/src/api/token-info.ts
@@ -15,17 +15,20 @@ export default async function tokenInfo(
 
   const queryString = stringify({
     client_id: clientId,
-    configs: generateConfigs()
-  })
+    configs: generateConfigs(),
+  });
 
   try {
-    const response = await fetch(`${MY_ACCOUNT_DOMAINS[mode]}/oauth/token/info.json?${queryString}`, {
-      method: 'GET',
-      headers: {
-        Authorization: `Bearer ${token}`,
-        'API-Version': '1604911588',
-      },
-    });
+    const response = await fetch(
+      `${MY_ACCOUNT_DOMAINS[mode]}/oauth/token/info.json?${queryString}`,
+      {
+        method: 'GET',
+        headers: {
+          Authorization: `Bearer ${token}`,
+          'API-Version': '1604911588',
+        },
+      }
+    );
 
     const result = await response.json();
 
diff --git a/yarn.lock b/yarn.lock
index 349d315..1e096bc 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -858,6 +858,11 @@
   resolved "https://registry.yarnpkg.com/@types/url-safe-base64/-/url-safe-base64-1.1.0.tgz#90d35b9432164896a9d5b3d43bb88fb2ef86f2e2"
   integrity sha512-cVZIEorjpbV8NgdodMXyLItd9q0wT4k075a2F5Ew5L/zwB80rLIGhb7Owo17le0hhnZcJXizxc7hHdTs1or51A==
 
+"@types/uuid@^8.3.0":
+  version "8.3.0"
+  resolved "https://registry.yarnpkg.com/@types/uuid/-/uuid-8.3.0.tgz#215c231dff736d5ba92410e6d602050cce7e273f"
+  integrity sha512-eQ9qFW/fhfGJF8WKHGEHZEyVWfZxrT+6CLIJGBcZPfxUh/+BnEj+UCGYMlr9qZuX/2AltsvwrGqp0LhEW8D0zQ==
+
 "@types/yargs-parser@*":
   version "15.0.0"
   resolved "https://registry.yarnpkg.com/@types/yargs-parser/-/yargs-parser-15.0.0.tgz#cb3f9f741869e20cce330ffbeb9271590483882d"