message: docs: about Authentication
diff: @@ -46,6 +46,35 @@ client.record
  | basicAuth | Object | | If your Kintone environment uses [Basic authentication](https://developer.kintone.io/hc/en-us/articles/212495188#basicauthentication), please specify its username and password. |
  | basicAuth.username | String | | The username of Basic authentication. |
  | basicAuth.password | String | | The password of Basic authentication. |
  +
  +### Authentication
  +
  +This client supports three authentication methods:
  +
  +1. [Password authentication](https://developer.kintone.io/hc/en-us/articles/212495188#passwordAuth)
  +2. [API token authentication](https://developer.kintone.io/hc/en-us/articles/212495188#APItokenAuth)
  +3. [Session authentication](https://developer.kintone.io/hc/en-us/articles/212495188#sessionAuth)
  +
  +> _TODO: Something like: "The required parameters are different by the methods. The client judges which method to use by passed parameters"_
  +
  +#### 1. Parameters for [Password authentication](https://developer.kintone.io/hc/en-us/articles/212495188#passwordAuth)
  +
  +| Name | Type | Required | Description |
  +| -------- | :----: | :------: | ----------- |
  +| username | String | Yes |
  +| password | String | Yes |
  +
  +#### 2. Parameters for [API token authentication](https://developer.kintone.io/hc/en-us/articles/212495188#APItokenAuth)
  +
  +| Name | Type | Required | Description |
  +| -------- | :----------------: | :------: | ------------------------------------------------------- |
  +| apiToken | String or String[] | Yes | You can pass multiple api tokens as an array of string. |
  +
  +#### 3. [Session authentication](https://developer.kintone.io/hc/en-us/articles/212495188#sessionAuth)
  +
  +Supported in browser environment only.
  +If you omit `auth` parameter, the client uses Session authentication.
  +
  ## KintoneRestAPIError
  ## References
  