> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mx.com/llms.txt
> Use this file to discover all available pages before exploring further.

# User Fields

> User fields for the MDX On Demand API.

## User Fields

| Field Name                   | Data Type | Description                                                                                                                         |
| ---------------------------- | --------- | ----------------------------------------------------------------------------------------------------------------------------------- |
| `birthdate`                  | `String`  | Birthdate of the user in ISO 8601 format (YYYY-MM-DD). No timestamp.                                                                |
| `credit_score`               | `Integer` | Credit score of the user.                                                                                                           |
| `email`                      | `String`  | Email address of the user. Max length 100. Must follow standard email formatting rules ([user@domain.tld](mailto:user@domain.tld)). |
| `first_name`                 | `String`  | First name of the user. Max length 50.                                                                                              |
| `gender`                     | `String`  | User gender: `MALE` or `FEMALE`.                                                                                                    |
| `guid`                       | `String`  | Unique identifier for the user. Defined by MX.                                                                                      |
| `id`                         | `String`  | Partner-defined unique user identifier. Max length 1024.                                                                            |
| `is_disabled`                | `Boolean` | Indicates whether the user is disabled from logging in. Defaults to false.                                                          |
| `is_excluded_from_analytics` | `Boolean` | Indicates whether user is excluded from analytics.                                                                                  |
| `last_name`                  | `String`  | Last name of the user. Max length 50.                                                                                               |
| `metadata`                   | `String`  | Additional partner-defined user metadata.                                                                                           |
| `phone`                      | `String`  | Phone number of the user. Max length 15.                                                                                            |
| `zip_code`                   | `String`  | Postal code of the user (supported countries include US, Canada, Japan, etc.).                                                      |