---
title: "API Inputs"
description: "Input and response fields for the Authentication API."
url: "https://developer-beta.morningstar.com/authentication-api/api-inputs"
image: "https://developer-beta.morningstar.com/_og/d/c_Ocean.takumi,title_~QVBJIElucHV0cyB8IEF1dGhlbnRpY2F0aW9uIEFQSQ,description_Input+and+response+fields+for+the+Authentication+API.,props_eyJ0aGVtZSI6eyJtb2RlIjoibGlnaHQiLCJjb2xvcnMiOnsicHJpbWFyeSI6IiMwMDAwMDAifX19,p_Ii9hdXRoZW50aWNhdGlvbi1hcGkvYXBpLWlucHV0cyI,s_lQQzC9mecnKQr22x.png"
---

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# Authentication API

Generate access tokens that authorize API calls.

# API Inputs

[View Markdown](https://developer-beta.morningstar.com/authentication-api/api-inputs.md)[Download Markdown](https://developer-beta.morningstar.com/authentication-api/api-inputs.md)

## [Request Inputs](#request-inputs)

The token request has one input, a header. It has no query parameters and no body.

### [Authorization](#authorization)

| Attribute       | Value                                    |
| :-------------- | :--------------------------------------- |
| Type            | Header                                   |
| Data Type       | string                                   |
| Possible Values | Basic {Base64-encoded username:password} |
| Example         | Basic dXNlcm5hbWU6cGFzc3dvcmQ=           |

Specifies your credentials, as a Base64-encoded `username:password` string with the `Basic` scheme. Required. Encode the username and password as one string, with the colon between them.

## [Response Fields](#response-fields)

These fields are returned by a successful token request.

### [access\_token](#access_token)

| Attribute       | Value                   |
| :-------------- | :---------------------- |
| Type            | Response Payload        |
| Data Type       | string                  |
| Possible Values | A signed JSON Web Token |
| Example         | eyJhbGciOiJ...          |

The token to use as a `Bearer` token in the `Authorization` header of requests to the other APIs.

### [expires\_in](#expires_in)

| Attribute       | Value                                         |
| :-------------- | :-------------------------------------------- |
| Type            | Response Payload                              |
| Data Type       | integer                                       |
| Possible Values | The number of seconds until the token expires |
| Example         | 3599                                          |

The number of seconds until the token expires. After expiry, request a new token.

### [token\_type](#token_type)

| Attribute       | Value            |
| :-------------- | :--------------- |
| Type            | Response Payload |
| Data Type       | string           |
| Possible Values | Bearer           |
| Example         | Bearer           |

The token type. The value is always `Bearer`.

## [Error Fields](#error-fields)

These fields are returned when the request fails.

### [error\_message](#error_message)

| Attribute       | Value                          |
| :-------------- | :----------------------------- |
| Type            | Response Payload               |
| Data Type       | string                         |
| Possible Values | A description of the error     |
| Example         | Incorrect username or password |

A human-readable description of the error.