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

# Introduction

> Understand general concepts, response codes, and authentication strategies.

## Base URL

The hellomateo API is built on REST principles. We enforce HTTPS in every request to improve data security, integrity, and privacy. The API does not support HTTP.

All requests contain the following base URL:

```
https://integration.getmateo.com/api/v1
```

## Authentication

To authenticate you need to add an Authorization header with the contents of the header being Bearer 123456789 where 123456789 is your API Key.

```
Authorization: Bearer 123456789
```

## Response Codes

Mateo uses standard HTTP codes to indicate the success or failure of your requests.

In general, `2xx` HTTP codes correspond to success, `4xx` codes are for user-related failures, and `5xx` codes are for infrastructure issues.

| Status | Description                                 |
| ------ | ------------------------------------------- |
| 200    | Successful request.                         |
| 400    | Check that the parameters were correct.     |
| 401    | The API key used was missing.               |
| 403    | The API key used was invalid.               |
| 404    | The resource was not found.                 |
| 429    | The rate limit was exceeded.                |
| 5xx    | Indicates an error with hellomateo servers. |

### Error Response

All error responses are of type `application/json` and return a body with the following structure:

```json theme={null}
{
  "code": "API_ERROR_CODE",
  "message": "A human-readable message explaining the error.",
  "hint": "A human-readable message explaining how to fix the error.",
  "status": 400
}
```