diff --git a/packages/authgear-core/src/error.ts b/packages/authgear-core/src/error.ts
index 1faa6361..2528a77a 100644
--- a/packages/authgear-core/src/error.ts
+++ b/packages/authgear-core/src/error.ts
@@ -20,14 +20,50 @@ export class AuthgearError extends Error {
  * @public
  */
 export enum ErrorName {
+  /**
+   * Indicates that the server does not understand the request (i.e. syntactic error).
+   * Status code: 400
+   */
   BadRequest = "BadRequest",
+  /**
+   * Indicates that the server understands the request, but refuse to process it (i.e. semantic error).
+   * Status code: 400
+   */
   Invalid = "Invalid",
+  /**
+   * Indicates that the client does not have valid credentials (i.e. authentication error).
+   * Status code: 401
+   */
   Unauthorized = "Unauthorized",
+  /**
+   * Indicates that the client's credentials are not allowed for the request (i.e. authorization error).
+   * Status code: 403
+   */
   Forbidden = "Forbidden",
+  /**
+   * Indicates that the server cannot find the requested resource.
+   * Status code: 404
+   */
   NotFound = "NotFound",
+  /**
+   * Indicates that the resource is already exists on the server.
+   * Status code: 409
+   */
   AlreadyExists = "AlreadyExists",
+  /**
+   * Indicates that the client has sent too many requests in a given amount of time.
+   * Status code: 429
+   */
   TooManyRequest = "TooManyRequest",
+  /**
+   * Indicates that the server encountered an unexpected condition and unable to process the request.
+   * Status code: 500
+   */
   InternalError = "InternalError",
+  /**
+   * Indicates that the server is not ready to handle the request.
+   * Status code: 503
+   */
   ServiceUnavailable = "ServiceUnavailable",
 }
 
@@ -143,28 +179,31 @@ export function _decodeError(err: any): Error {
 }
 
 /**
- * PreAuthenticatedURLNotAllowedError
+ * PreAuthenticatedURLNotAllowedError is the root class of errors related to pre-authenticated URL.
  *
  * @public
  */
 export class PreAuthenticatedURLNotAllowedError extends AuthgearError {}
 
 /**
- * PreAuthenticatedURLInsufficientScopeError
+ * This may happen if the "Pre-authenticated URL" feature was not enabled when the user logged in during this session.
+ * Ask the user to log in again to enable this feature.
  *
  * @public
  */
 export class PreAuthenticatedURLInsufficientScopeError extends PreAuthenticatedURLNotAllowedError {}
 
 /**
- * PreAuthenticatedURLIDTokenNotFoundError
+ * The user logged in from an older SDK version that does not support the pre-authenticated URL.
+ * Ask the user to log in again to resolve the problem.
  *
  * @public
  */
 export class PreAuthenticatedURLIDTokenNotFoundError extends PreAuthenticatedURLNotAllowedError {}
 
 /**
- * PreAuthenticatedURLDeviceSecretNotFoundError
+ * The device secret is not found. This may happen if the "Pre-authenticated URL" feature was not enabled when the user logged in during this session.
+ * Ask the user to log in again to enable this feature.
  *
  * @public
  */
diff --git a/packages/authgear-core/src/types.ts b/packages/authgear-core/src/types.ts
index e2c6e96c..1fc1813b 100644
--- a/packages/authgear-core/src/types.ts
+++ b/packages/authgear-core/src/types.ts
@@ -1,7 +1,11 @@
 /**
  * UserInfo is the result of fetchUserInfo.
  * It contains `sub` which is the User ID,
- * as well OIDC standard claims like `email`.
+ * as well as OIDC standard claims like `email`,
+ * see https://openid.net/specs/openid-connect-core-1_0.html#StandardClaims.
+ *
+ * In addition to these standard claims, it may include custom claims
+ * defined by Authgear to support additional functionality like `isVerified`.
  *
  * @public
  */
@@ -49,7 +53,13 @@ export interface UserInfo {
  * @public
  */
 export enum ColorScheme {
+  /**
+   * Force to use the light color scheme in the AuthUI when the project config is "Auto".
+   */
   Light = "light",
+  /**
+   * Force to use the dark color scheme in the AuthUI when the project config is "Auto".
+   */
   Dark = "dark",
 }
 
@@ -59,9 +69,28 @@ export enum ColorScheme {
  * @public
  */
 export enum PromptOption {
+  /**
+   * The `none` prompt is used to sliently authenticate the user without prompting for any action.
+   * This prompt bypasses the need for `login` and `consent` prompts
+   * only when the user has previously given consent to the application and has an active session.
+   */
   None = "none",
+  /**
+   * The `login` prompt requires the user to log in to the authentication provider which forces the user to re-authenticate.
+   */
   Login = "login",
+  /**
+   * The `consent` prompt asks the user to consent to the scopes.
+   *
+   * @internal
+   */
   Consent = "consent",
+  /**
+   * The select_account prompt present a "Continue" screen to for the user to choose
+   * to continue with the session in the cookies or login to another account.
+   *
+   * @internal
+   */
   SelectAccount = "select_account",
 }
 
@@ -212,8 +241,17 @@ export interface _AnonymousUserPromotionCodeResponse {
  * @public
  */
 export interface TokenStorage {
+  /**
+   * Stores a refresh token for a give namespace to the storage.
+   */
   setRefreshToken(namespace: string, refreshToken: string): Promise<void>;
+  /**
+   * Retrieves the refresh token associated with a specific namespace in the storage.
+   */
   getRefreshToken(namespace: string): Promise<string | null>;
+  /**
+   * Deletes the refresh token for the specified namespace in the storage.
+   */
   delRefreshToken(namespace: string): Promise<void>;
 }
 
@@ -268,6 +306,11 @@ export interface _StorageDriver {
  * @public
  */
 export interface ContainerOptions {
+  /**
+   * The name of the container. The name is used as the namespace of `TokenStorage`.
+   * One use case is to use multiple containers with different names to support signing in multiple accounts.
+   * @defaultValue "default"
+   */
   name?: string;
 }
 
@@ -341,6 +384,8 @@ export interface _OIDCTokenResponse {
  * After a call to configure, the session state would become "AUTHENTICATED" if a previous session was found,
  * or "NO_SESSION" if such session was not found.
  *
+ * Please refer to {@link SessionStateChangeReason} for more information.
+ *
  * @public
  */
 export enum SessionState {
@@ -355,7 +400,7 @@ export enum SessionState {
  * These reasons can be thought of as the transition of a SessionState, which is described as follows:
  *
  * ```
- *                                                          LOGOUT / INVALID
+ *                                                      LOGOUT / INVALID / CLEAR
  *                                           +----------------------------------------------+
  *                                           v                                              |
  *    State: UNKNOWN ----- NO_TOKEN ----> State: NO_SESSION ---- AUTHENTICATED -----> State: AUTHENTICATED
@@ -375,18 +420,34 @@ export enum SessionStateChangeReason {
 }
 
 /**
+ * The path of the page in Authgear.
+ *
  * @public
  */
 export enum Page {
+  /**
+   * The path of the settings page in Authgear.
+   */
   Settings = "/settings",
+  /**
+   * The path of the indenties page in Authgear.
+   */
   Identities = "/settings/identities",
 }
 
 /**
+ * The actions that can be performed in Authgear settings page.
+ *
  * @public
  */
 export enum SettingsAction {
+  /**
+   * Change password in Authgear settings page.
+   */
   ChangePassword = "change_password",
+  /**
+   * Delete account in Authgear settings page.
+   */
   DeleteAccount = "delete_account",
 }
 
diff --git a/packages/authgear-react-native/src/index.ts b/packages/authgear-react-native/src/index.ts
index c7e22308..d38fa4b1 100644
--- a/packages/authgear-react-native/src/index.ts
+++ b/packages/authgear-react-native/src/index.ts
@@ -75,15 +75,17 @@ export {
 export * from "./ui_implementation";
 
 /**
+ * ConfigureOptions is options for configuring the Authgear SDK container.
+ *
  * @public
  */
 export interface ConfigureOptions {
   /**
-   * The OAuth client ID.
+   * The OAuth client ID. You may find this value in Authgear Portal (Your project \> Applications).
    */
   clientID: string;
   /**
-   * The endpoint.
+   * The endpoint. You may find this value in Authgear Portal (Your project \> Applications).
    */
   endpoint: string;
 
@@ -107,8 +109,8 @@ export interface ConfigureOptions {
    */
   preAuthenticatedURLEnabled?: boolean;
 
-  /*
-   * The UIImplementation.
+  /**
+   * The implementation of UIImplementation.
    */
   uiImplementation?: UIImplementation;
 }
@@ -177,13 +179,16 @@ export class ReactNativeContainer {
   wechatRedirectDeepLinkListener: (url: string) => void;
 
   /**
+   * Delegation for customizing the behavior of your application.
+   * You can implement your own delegation and the container will evaluate them if needed.
+   *
    * @public
    */
   delegate?: ReactNativeContainerDelegate;
 
   /**
-   *
-   * Unique ID for this container.
+   * The name of the container. The name is used as the namespace of `TokenStorage`.
+   * One use case is to use multiple containers with different names to support signing in multiple accounts.
    * @defaultValue "default"
    *
    * @public
@@ -236,6 +241,7 @@ export class ReactNativeContainer {
   }
 
   /**
+   * The current SessionState of this container.
    *
    * @public
    */
@@ -248,6 +254,7 @@ export class ReactNativeContainer {
   }
 
   /**
+   * The access token of this container.
    *
    * @public
    */
@@ -436,7 +443,12 @@ export class ReactNativeContainer {
   }
 
   /**
-   * Authenticate the end user via the web.
+   * authenticate() starts the authentication process in a {@link UIImplementation}.
+   * After authentication, the {@link UIImplementation} will be closed and the user is logged in.
+   * After this method resolves, biometric authentication is disabled.
+   * Call enableBiometric() again to enable biometric authentication for the new signed in user.
+   *
+   * You can refer to {@link AuthenticateOptions} for more customization.
    *
    * @public
    */
@@ -523,6 +535,11 @@ export class ReactNativeContainer {
   }
 
   /**
+   * changePassword() opens the settings page in a {@link UIImplementation} for the user to change their password.
+   * After changing the password, the {@link UIImplementation} will be closed.
+   *
+   * You can refer to {@link SettingsActionOptions} for more customization.
+   *
    * @public
    */
   async changePassword(options: SettingsActionOptions): Promise<void> {
@@ -530,6 +547,11 @@ export class ReactNativeContainer {
   }
 
   /**
+   * deleteAccount() opens the settings page in a {@link UIImplementation} for the user to delete their account.
+   * After deletion, the {@link UIImplementation} will be closed and the user is logged out.
+   *
+   * You can refer to {@link SettingsActionOptions} for more customization.
+   *
    * @public
    */
   async deleteAccount(options: SettingsActionOptions): Promise<void> {
@@ -538,10 +560,12 @@ export class ReactNativeContainer {
   }
 
   /**
-   * Reauthenticate the end user via biometric or the web.
+   * reauthenticate() starts the reauthentication process via biometric or in the {@link UIImplementation}.
    *
    * If biometricOptions is given, biometric is used when possible.
    *
+   * You can refer to {@link ReauthenticateOptions} and {@link BiometricOptions} for more customization.
+   *
    * @public
    */
   async reauthenticate(
@@ -658,18 +682,28 @@ export class ReactNativeContainer {
     await this.openURL(`${endpoint.origin}${path}`, options);
   }
 
+  /**
+   * Open Authgear pages. Currently only settings pages are available.
+   *
+   * You can refer to {@link SettingOptions} for more customization.
+   *
+   * @public
+   */
   async open(page: Page, options?: SettingOptions): Promise<void> {
     await this.openAuthgearURL(page, options);
   }
 
   /**
-   * Logout.
+   * logout() signs out the user without showing any UI. The refresh token will be cleared.
+   * The biometric authentication is kept, so the user can authenticateBiometric again.
    *
    * @remarks
    * If `force` parameter is set to `true`, all potential errors (e.g. network
    * error) would be ignored.
    *
    * @param options - Logout options
+   *
+   * @public
    */
   async logout(
     options: {
@@ -691,7 +725,10 @@ export class ReactNativeContainer {
   }
 
   /**
-   * Authenticate as an anonymous user.
+   * authenticateAnonymously() creates an anonymous user without showing any UI.
+   * You may first enable Anonymous Users in Authgear Portal (Your project \> Authentication \> Anonymous Users \> Enable anonymous users).
+   *
+   * @public
    */
   async authenticateAnonymously(): Promise<AuthenticateResult> {
     const clientID = this.clientID;
@@ -736,9 +773,14 @@ export class ReactNativeContainer {
   }
 
   /**
-   * Open promote anonymous user page
+   * promoteAnonymousUser() opens the anonymous user promotion page in the {@link UIImplementation} and the user has to authenticate.
+   * The flow is similar to authenticate(), the {@link UIImplementation} will be closed and the user is logged in after authentication.
+   * After this method resolves, biometric authentication is disabled.
+   * Call enableBiometric() again to enable biometric authentication for the new signed in user.
+   *
+   * You can refer to {@link PromoteOptions} for more customization.
    *
-   * @param options - promote options
+   * @public
    */
   async promoteAnonymousUser(
     options: PromoteOptions
@@ -819,7 +861,9 @@ export class ReactNativeContainer {
   }
 
   /**
-   * Fetch user info.
+   * fetchUserInfo() fetches the up-to-date user info.
+   *
+   * @public
    */
   async fetchUserInfo(): Promise<UserInfo> {
     await this.refreshAccessTokenIfNeeded();
@@ -839,6 +883,9 @@ export class ReactNativeContainer {
   }
 
   /**
+   * refreshAccessTokenIfNeeded() refreshes the access token if needed.
+   * After the task has completed, the updated access token will be stored in this.accessToken.
+   *
    * @public
    */
   async refreshAccessTokenIfNeeded(): Promise<void> {
@@ -862,6 +909,8 @@ export class ReactNativeContainer {
    *
    * @param code - WeChat Authorization code.
    * @param state - WeChat Authorization state.
+   *
+   * @public
    */
   async wechatAuthCallback(code: string, state: string): Promise<void> {
     return this.baseContainer.apiClient._wechatAuthCallbackRequest(
@@ -886,6 +935,8 @@ export class ReactNativeContainer {
   /**
    * Check whether biometric is supported on the current device.
    * If biometric is not supported, then a platform specific error is thrown.
+   *
+   * @public
    */
   // eslint-disable-next-line class-methods-use-this
   async checkBiometricSupported(options: BiometricOptions): Promise<void> {
@@ -893,13 +944,21 @@ export class ReactNativeContainer {
   }
 
   /**
-   * Check whether biometric was enabled for the last logged in user.
+   * Check whether biometric was enabled for the signed in user.
+   *
+   * @public
    */
   async isBiometricEnabled(): Promise<boolean> {
     const keyID = await this.storage.getBiometricKeyID(this.name);
     return keyID != null;
   }
 
+  /**
+   * Disable biometric authentication for the signed in user.
+   * After disabling, the user may not be able to authenticate with biometric until it is enabled again.
+   *
+   * @public
+   */
   async disableBiometric(): Promise<void> {
     const keyID = await this.storage.getBiometricKeyID(this.name);
     if (keyID != null) {
@@ -908,6 +967,15 @@ export class ReactNativeContainer {
     }
   }
 
+  /**
+   * Enable biometric authentication for the signed in user.
+   * Platform specific biometric authentication UI will be shown.
+   * You may first enable biometric authentication in Authgear Portal (Your Project \> Authentication \> Biometric \> Enable biometric authentication).
+   *
+   * You can refer to {@link BiometricOptions} for more customization.
+   *
+   * @public
+   */
   async enableBiometric(options: BiometricOptions): Promise<void> {
     const clientID = this.clientID;
     if (clientID == null) {
@@ -945,6 +1013,15 @@ export class ReactNativeContainer {
     await this.storage.setBiometricKeyID(this.name, kid);
   }
 
+  /**
+   * Authenticate with biometric authentication.
+   * Platform specific biometric authentication UI will be shown.
+   * You may first enable biometric authentication in Authgear Portal (Your Project \> Authentication \> Biometric \> Enable biometric authentication).
+   *
+   * You can refer to {@link BiometricOptions} for more customization.
+   *
+   * @public
+   */
   async authenticateBiometric(
     options: BiometricOptions
   ): Promise<AuthenticateResult> {
@@ -1011,7 +1088,9 @@ export class ReactNativeContainer {
   /**
    * Share the current authenticated session to a web browser.
    *
-   * `preAuthenticatedURLEnabled` must be set to true to use this method.
+   * `ConfigureOptions.preAuthenticatedURLEnabled` must be set to true to use this method.
+   *
+   * You can refer to {@link PreAuthenticatedURLOptions} for more customization.
    *
    * @public
    */
diff --git a/packages/authgear-react-native/src/types.ts b/packages/authgear-react-native/src/types.ts
index fa49626d..03ae2915 100644
--- a/packages/authgear-react-native/src/types.ts
+++ b/packages/authgear-react-native/src/types.ts
@@ -7,6 +7,10 @@ import {
 import { ReactNativeContainer } from ".";
 
 /**
+ * ReactNativeContainerDelegate defines a set of functions that the SDK container will use.
+ *
+ * You can implement these functions to customize the behavior of your application.
+ *
  * @public
  */
 export interface ReactNativeContainerDelegate {
@@ -196,7 +200,7 @@ export interface PromoteOptions {
  */
 export interface AuthenticateResult {
   /**
-   * UserInfo.
+   * The updated user info after authentication.
    */
   userInfo: UserInfo;
 }
@@ -208,12 +212,15 @@ export interface AuthenticateResult {
  */
 export interface ReauthenticateResult {
   /**
-   * UserInfo.
+   * The updated user info after reauthentication.
    */
   userInfo: UserInfo;
 }
 
 /**
+ * Options that used by {@link ReactNativeContainer.open}.
+ * It allows you to configure the UI of the opened settings page.
+ *
  * @public
  */
 export interface SettingOptions {
@@ -238,6 +245,9 @@ export interface SettingOptions {
 }
 
 /**
+ * It is similar to {@link SettingOptions}, but it is used for configuring
+ * the UI of the opened settings page for specific action like `SettingsAction.ChangePassword`.
+ *
  * @public
  */
 export interface SettingsActionOptions {
@@ -335,7 +345,21 @@ export interface BiometricOptionsIOS {
    * @public
    */
   localizedReason: string;
+  /**
+   * Set the contraint for the authenticator to be used for biometric authentication.
+   *
+   * See {@link BiometricAccessConstraintIOS}
+   *
+   * @public
+   */
   constraint: BiometricAccessConstraintIOS;
+  /**
+   * Set the local authentication policy for biometric authentication.
+   *
+   * See {@link BiometricLAPolicy}
+   *
+   * @public
+   */
   policy: BiometricLAPolicy;
 }
 
@@ -393,6 +417,13 @@ export interface BiometricOptionsAndroid {
    * @public
    */
   negativeButtonText: string;
+  /**
+   * Set the contraint for the authenticator to be used for biometric authentication.
+   *
+   * See {@link BiometricAccessConstraintAndroid}
+   *
+   * @public
+   */
   constraint: BiometricAccessConstraintAndroid[];
   /**
    * The user needs to set up biometric again when a new biometric is enrolled or all enrolled biometrics are removed.
@@ -406,6 +437,7 @@ export interface BiometricOptionsAndroid {
 
 /**
  * BiometricOptions is options for biometric authentication.
+ * It allows platform-specific customization for iOS and Android.
  *
  * @public
  */
diff --git a/packages/authgear-react-native/src/ui_implementation.ts b/packages/authgear-react-native/src/ui_implementation.ts
index 9f9c1328..b8fb88b7 100644
--- a/packages/authgear-react-native/src/ui_implementation.ts
+++ b/packages/authgear-react-native/src/ui_implementation.ts
@@ -1,19 +1,24 @@
 import { openAuthorizeURL, openAuthorizeURLWithWebView } from "./nativemodule";
 
 /**
+ * OpenAuthorizationURLOptions is options for {@link UIImplementation.openAuthorizationURL}.
+ *
  * @public
  */
 export interface OpenAuthorizationURLOptions {
-  /*
-   * The URL to open.
+  /**
+   * The URL to be opened by the UIImplementation.
    */
   url: string;
-  /*
-   * The URL to detect.
+  /**
+   * The URL to be detected by the UIImplementation.
+   * When this URL is detected, the UIImplementation MUST return this URL, and close itself.
    */
   redirectURI: string;
-  /*
-   * A flag to some implementations that can share cookies with the device browser.
+  /**
+   * A flag to tell the UIImplementation that cookies should be shared with the device browser.
+   * This flag is only useful to UIImplementation that can share cookies with the device browser,
+   * such as those underlying implementations are based on ASWebAuthenticationSession, or CustomTabs.
    */
   shareCookiesWithDeviceBrowser: boolean;
 }
@@ -36,7 +41,10 @@ export interface UIImplementation {
 }
 
 /**
- * DeviceBrowserUIImplementation is ASWebAuthenticationSession on iOS, and Custom Tabs on Android.
+ * DeviceBrowserUIImplementation is the default {@link UIImplementation}.
+ *
+ * For iOS, it is using ASWebAuthenticationSession (see https://developer.apple.com/documentation/authenticationservices/aswebauthenticationsession).
+ * For Android, it is using Custom Tabs (see https://developer.chrome.com/docs/android/custom-tabs).
  *
  * @public
  */
@@ -56,28 +64,52 @@ export class DeviceBrowserUIImplementation implements UIImplementation {
 }
 
 /**
- * Color is an integer according to this encoding https://developer.android.com/reference/android/graphics/Color#encoding
+ * Color is an integer according to this encoding https://developer.android.com/reference/android/graphics/Color#encoding.
+ * Yes, it is still from Android such that the color encoding method in iOS is the same that used in Android.
  *
  * @public
  */
 export interface WebKitWebViewUIImplementationOptionsIOS {
+  /**
+   * The color is in hexadecimal format representing the argb, for example, blue is 0xff0000ff.
+   */
   navigationBarBackgroundColor?: number;
+  /**
+   * The color is in hexadecimal format representing the argb, for example, blue is 0xff0000ff.
+   */
   navigationBarButtonTintColor?: number;
+  /**
+   * Styles for the modal.
+   * See https://developer.apple.com/documentation/uikit/uimodalpresentationstyle.
+   */
   modalPresentationStyle?: "automatic" | "fullScreen" | "pageSheet";
+  /**
+   * Indicates whether you can inspect the view with Safari Web Inspector.
+   * See https://developer.apple.com/documentation/webkit/wkwebview/4111163-isinspectable.
+   */
   isInspectable?: boolean;
 }
 
 /**
- * Color is an integer according to this encoding https://developer.android.com/reference/android/graphics/Color#encoding
+ * Color is an integer according to this encoding https://developer.android.com/reference/android/graphics/Color#encoding.
  *
  * @public
  */
 export interface WebKitWebViewUIImplementationOptionsAndroid {
+  /**
+   * The color is in hexadecimal format representing the argb, for example, blue is 0xff0000ff.
+   */
   actionBarBackgroundColor?: number;
+  /**
+   * The color is in hexadecimal format representing the argb, for example, blue is 0xff0000ff.
+   */
   actionBarButtonTintColor?: number;
 }
 
 /**
+ * WebKitWebViewUIImplementationOptions specifies options for configuring the user interface of a WebKit WebView.
+ * It allows platform-specific customization for iOS and Android.
+ *
  * @public
  */
 export interface WebKitWebViewUIImplementationOptions {
@@ -86,7 +118,10 @@ export interface WebKitWebViewUIImplementationOptions {
 }
 
 /**
- * WebKitWebViewUIImplementation is WKWebView on iOS, android.webkit.WebView on Android.
+ * WebKitWebViewUIImplementation provides more customization options other than {@link DeviceBrowserUIImplementation}.
+ *
+ * For iOS, it is using WKWebView (see https://developer.apple.com/documentation/webkit/wkwebview).
+ * For Android, it is using android.webkit.WebView (see https://developer.android.com/reference/android/webkit/WebView).
  *
  * @public
  */