diff --git a/src/components/SettingsBar.js b/src/components/SettingsBar.js
index 9fcf448..c36cdb2 100644
--- a/src/components/SettingsBar.js
+++ b/src/components/SettingsBar.js
@@ -89,7 +89,14 @@ export default class SettingsBar extends React.PureComponent {
       onAccessTokenChange(accessToken)
       this.setState({
         accessToken: '',
-        accessTokenHint: <span><a href="#" onClick={() => window.location.reload()}>Reload</a> to activate!</span>,
+        accessTokenHint: (
+          <span>
+            <a href="#" onClick={() => window.location.reload()}>
+              Reload
+            </a>{' '}
+            to activate!
+          </span>
+        ),
       })
     }
   }
@@ -126,38 +133,44 @@ export default class SettingsBar extends React.PureComponent {
     const { setCompressSingleton } = this.props
     setCompressSingleton(compress)
     this.setState({
-      compressHint: <span>Saved, <a href="#" onClick={() => window.location.reload()}>reload</a> to apply.</span>,
+      compressHint: (
+        <span>
+          Saved,{' '}
+          <a href="#" onClick={() => window.location.reload()}>
+            reload
+          </a>{' '}
+          to apply.
+        </span>
+      ),
     })
   }
 
   render() {
-    const { accessTokenHint, toggleShowSideBarShortcut, compressSingletonFolder, shortcutHint, accessToken, compressHint } = this.state
+    const {
+      accessTokenHint,
+      toggleShowSideBarShortcut,
+      compressSingletonFolder,
+      shortcutHint,
+      accessToken,
+      compressHint,
+    } = this.state
     const { toggleShowSettings, activated, accessToken: hasAccessToken } = this.props
     return (
       <div className={'gitako-settings-bar'}>
         {activated && (
           <React.Fragment>
-            <h3 className={'gitako-settings-bar-title'}>
-              Settings
-            </h3>
+            <h3 className={'gitako-settings-bar-title'}>Settings</h3>
             <div className={'gitako-settings-bar-content'}>
               <div className={'shadow-shelter'} />
               <div className={'gitako-settings-bar-content-section access-token'}>
                 <h4>Access Token</h4>
-                <span>With access token provided, Gitako can access more repositories.</span>
-                <br />
-                <a href="https://github.com/blog/1509-personal-api-tokens" target="_blank">
-                  Help: how to create access token?
+                <a
+                  href="https://github.com/EnixCoda/Gitako/wiki/How-to-create-access-token-for-Gitako%3F"
+                  target="_blank"
+                >
+                  Why & how to create it?
                 </a>
                 <br />
-                <span>
-                  Gitako stores the token in&nbsp;
-                  <a href="https://developer.chrome.com/apps/storage" target="_blank">
-                    chrome local storage
-                  </a>
-                  &nbsp;locally and safely.
-                </span>
-                <br />
                 <div className={'access-token-input-control'}>
                   <input
                     className={'access-token-input form-control'}
@@ -199,10 +212,18 @@ export default class SettingsBar extends React.PureComponent {
               <div className={'gitako-settings-bar-content-section singleton'}>
                 <h4>
                   Compress singleton folder&nbsp;
-                  <a href={wikiLinks.compressSingletonFolder} target={'_blank'}>(?)</a>
+                  <a href={wikiLinks.compressSingletonFolder} target={'_blank'}>
+                    (?)
+                  </a>
                 </h4>
                 <label htmlFor={'compress-singleton-folder'}>
-                  <input id={'compress-singleton-folder'} name={'compress-singleton-folder'} type={'checkbox'} onChange={this.setCompressSingletonFolder} checked={compressSingletonFolder} />
+                  <input
+                    id={'compress-singleton-folder'}
+                    name={'compress-singleton-folder'}
+                    type={'checkbox'}
+                    onChange={this.setCompressSingletonFolder}
+                    checked={compressSingletonFolder}
+                  />
                   &nbsp; {compressSingletonFolder ? 'enabled' : 'disabled'}
                 </label>
                 {compressHint && <div className={'hint'}>{compressHint}</div>}
@@ -220,7 +241,12 @@ export default class SettingsBar extends React.PureComponent {
           </React.Fragment>
         )}
         <div className={'placeholder-row'}>
-          <a className={'version'} href={wikiLinks.changeLog} target={'_blank'} title={'Check out new features!'}>
+          <a
+            className={'version'}
+            href={wikiLinks.changeLog}
+            target={'_blank'}
+            title={'Check out new features!'}
+          >
             v{version}
           </a>
           {activated ? (
@@ -230,11 +256,7 @@ export default class SettingsBar extends React.PureComponent {
               onClick={toggleShowSettings}
             />
           ) : (
-            <Icon
-              type={'gear'}
-              className={'show-settings-icon'}
-              onClick={toggleShowSettings}
-            />
+            <Icon type={'gear'} className={'show-settings-icon'} onClick={toggleShowSettings} />
           )}
         </div>
       </div>
diff --git a/src/components/SideBar.js b/src/components/SideBar.js
index c43c8d7..e1d995c 100644
--- a/src/components/SideBar.js
+++ b/src/components/SideBar.js
@@ -79,23 +79,46 @@ export default class Gitako extends React.PureComponent {
       <div className={'description'}>
         <h5>Access Denied</h5>
         <p>
-          Gitako needs access token with proper scopes (recommended: repo) to access this
-          repository. Please save it in the settings below.
+          Due to{' '}
+          <a target="_blank" href="https://developer.github.com/v3/#rate-limiting">
+            limitation of GitHub
+          </a>{' '}
+          or{' '}
+          <a target="_blank" href="https://developer.github.com/v3/#authentication">
+            auth needs
+          </a>
+          , Gitako needs access token to continue. Please follow the instructions in the settings
+          panel below.
         </p>
       </div>
     )
   }
 
   renderContent() {
-    const { errorDueToAuth, metaData, treeData, showSettings, accessToken, compressSingletonFolder, toggleShowSettings } = this.props
+    const {
+      errorDueToAuth,
+      metaData,
+      treeData,
+      showSettings,
+      accessToken,
+      compressSingletonFolder,
+      toggleShowSettings,
+    } = this.props
     return (
       <div className={'gitako-side-bar-content'}>
         {metaData && <MetaBar metaData={metaData} />}
         {errorDueToAuth
           ? this.renderAccessDeniedError()
-          : metaData &&
-            <FileExplorer toggleShowSettings={toggleShowSettings} metaData={metaData} treeData={treeData} freeze={showSettings} accessToken={accessToken} compressSingletonFolder={compressSingletonFolder} />
-        }
+          : metaData && (
+              <FileExplorer
+                toggleShowSettings={toggleShowSettings}
+                metaData={metaData}
+                treeData={treeData}
+                freeze={showSettings}
+                accessToken={accessToken}
+                compressSingletonFolder={compressSingletonFolder}
+              />
+            )}
       </div>
     )
   }
@@ -119,7 +142,11 @@ export default class Gitako extends React.PureComponent {
     return (
       <div className={'gitako-side-bar'}>
         <Portal into={logoContainerElement}>
-          <ToggleShowButton error={error} shouldShow={shouldShow} toggleShowSideBar={toggleShowSideBar} />
+          <ToggleShowButton
+            error={error}
+            shouldShow={shouldShow}
+            toggleShowSideBar={toggleShowSideBar}
+          />
         </Portal>
         <Resizable className={cx({ hidden: error || !shouldShow })} baseSize={baseSize}>
           <div className={'gitako-side-bar-body'}>
@@ -133,7 +160,7 @@ export default class Gitako extends React.PureComponent {
               compressSingletonFolder={compressSingletonFolder}
               toggleShowSideBarShortcut={toggleShowSideBarShortcut}
               setCompressSingleton={setCompressSingleton}
-              />
+            />
           </div>
         </Resizable>
       </div>
diff --git a/src/driver/core/SideBar.js b/src/driver/core/SideBar.js
index 6ec6415..bad4925 100644
--- a/src/driver/core/SideBar.js
+++ b/src/driver/core/SideBar.js
@@ -1,5 +1,5 @@
 import DOMHelper, { REPO_TYPE_PRIVATE } from 'utils/DOMHelper'
-import GitHubHelper, { NOT_FOUND, BAD_CREDENTIALS } from 'utils/GitHubHelper'
+import GitHubHelper, { NOT_FOUND, BAD_CREDENTIALS, API_RATE_LIMIT } from 'utils/GitHubHelper'
 import configHelper from 'utils/configHelper'
 import URLHelper from 'utils/URLHelper'
 import keyHelper from 'utils/keyHelper'
@@ -53,9 +53,9 @@ const init = dispatch => async () => {
 
 const handleError = dispatch => async (err) => {
   // TODO: detect request time exceeds limit
-  if (err.message === NOT_FOUND || err.message === BAD_CREDENTIALS) {
+  if (err.message === NOT_FOUND || err.message === BAD_CREDENTIALS || err.message === API_RATE_LIMIT ) {
     const repoPageType = await DOMHelper.getRepoPageType()
-    const errorDueToAuth = repoPageType === REPO_TYPE_PRIVATE || err.message === BAD_CREDENTIALS
+    const errorDueToAuth = repoPageType === REPO_TYPE_PRIVATE || err.message === BAD_CREDENTIALS || err.message === API_RATE_LIMIT
     dispatch({ errorDueToAuth })
     dispatch(setShowSettings, true)
     dispatch(setShouldShow, errorDueToAuth)
diff --git a/src/utils/GitHubHelper.js b/src/utils/GitHubHelper.js
index 25bd775..5b11313 100644
--- a/src/utils/GitHubHelper.js
+++ b/src/utils/GitHubHelper.js
@@ -1,6 +1,11 @@
 import { raiseError } from 'analytics'
 export const NOT_FOUND = 'Repo Not Found'
 export const BAD_CREDENTIALS = 'Bad credentials'
+export const API_RATE_LIMIT = `API rate limit`
+
+function apiRateLimitExceeded(content) {
+  return content && content['documentation_url'] === 'https://developer.github.com/v3/#rate-limiting'
+}
 
 async function request(url, { accessToken } = {}) {
   const headers = {}
@@ -11,9 +16,12 @@ async function request(url, { accessToken } = {}) {
   if (res.status === 200) return res.json()
   // for private repo, GitHub api also responses with 404 when unauthorized
   else if (res.status === 404) throw new Error(NOT_FOUND)
-  else if (!res.ok) raiseError(new Error(`Got ${res.statusText} when requesting ${url}`))
-  const content = await res.json()
-  throw new Error(content && content.message)
+  else {
+    const content = await res.json()
+    if (apiRateLimitExceeded(content)) throw new Error(API_RATE_LIMIT)
+    else if (!res.ok) raiseError(new Error(`Got ${res.statusText} when requesting ${url}`))
+    throw new Error(content && content.message)
+  }
 }
 
 async function getRepoMeta({ userName, repoName, accessToken }) {