> For the complete documentation index, see [llms.txt](https://docs.altum.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.altum.ai/english/property-valuation-and-market/avm+-api/authentication-input-and-response.md).

# Authentication, input and response

## Post object data to receive an accurate automated model valuation

<mark style="color:green;">`POST`</mark> `https://api.altum.ai/avmplus`

This endpoint allows you to receive response from the Altum AI AVM+ model.

#### Headers

| Name                                        | Type   | Description                                                                 |
| ------------------------------------------- | ------ | --------------------------------------------------------------------------- |
| Content-Type                                | string | application/json                                                            |
| x-api-key<mark style="color:red;">\*</mark> | string | Unique API key from Altum. Create one via Mopsus(<https://mopsus.altum.ai>) |

#### Request Body

| Name                                          | Type   | Description                               |
| --------------------------------------------- | ------ | ----------------------------------------- |
| postcode<mark style="color:red;">\*</mark>    | string | Postcode of the object                    |
| valuation\_date                               | string | Valuation date (default is date of entry) |
| houseaddition                                 | string | House number letters and/or addition      |
| housenumber<mark style="color:red;">\*</mark> | number | House number                              |
| energylabel                                   | string | Energy label A++++ till G                 |
| innersurfacearea                              | number | Square meter (m2) inner surface area      |
| outersurfacearea                              | number | Square meter (m2) outer surface area      |

{% tabs %}
{% tab title="401: Unauthorized No access" %}

```
{
    'Output': 'Please use https://api.altum.ai or visit https://mopsus.altum.ai to make your request.'
}
```

{% endtab %}

{% tab title="403: Forbidden Forbidden" %}

```
{
	"message": "Missing Authentication Token"
}
```

{% endtab %}

{% tab title="429: Too Many Requests API key limit exceeded" %}

{% endtab %}

{% tab title="500: Internal Server Error Service is not available and/or down" %}

```
{
	"message": "Internal server error"
}
```

{% endtab %}

{% tab title="422: Unprocessable Entity Wrong input format" %}

```
{
  "detail": [
    {
      "loc": [
        "body",
        "postcode"
      ],
      "msg": "string does not match regex \"^(?!1000|1001|1002|1003|1004|1005|1006|1007|1008|1009|1010)[1-9][0-9]{3}[A-Z]{2}$\"",
      "type": "value_error.str.regex",
      "ctx": {
        "pattern": "^(?!1000|1001|1002|1003|1004|1005|1006|1007|1008|1009|1010)[1-9][0-9]{3}[A-Z]{2}$"
      }
    }
  ]
}
```

{% endtab %}

{% tab title="200: OK Successful response" %}

```
{
	"bagid": "0363010000735772",
	"postcode": "1024CT",
	"housenumber": "25",
	"houseaddition": "",
	"city": "Amsterdam",
	"street": "Markengouw",
	"housetype": "Portiekwoning",
	"buildyear": "1967",
	"innersurfacearea": "76",
	"outersurfacearea": "3299",
	"volume": "2211",
	"energylabel": "D",
	"longitude": "4.96144831561363",
	"latitude": "52.39109040866619",
	"valuationdate": "20231120",
	"priceestimation": "278082",
	"confidence": "90% Confidence Interval is 250273-305890."
}
```

{% endtab %}

{% tab title="400: Bad Request Unsuccessful response" %}

```
{
  "Output": "The given house address not found in database, the combination of Post Code, House Number and House Addition does not exist."
}

{
  'Unsupported evaluation date format, it should be YYYYMMDD.'
}

{
  'The evaluation date range should be from {} and until {}.'
}

{
  'Output': 'We are not able to provide prediction at the moment.'
}

{
  'Output': 'The prediction is too low.'
}
```

{% endtab %}
{% endtabs %}

## Request body

#### Example request

```
{
  "postcode": "1024CT",
  "housenumber": 25,
  "houseaddition": "",
  "valuation_date": "20230112"
}
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.altum.ai/english/property-valuation-and-market/avm+-api/authentication-input-and-response.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.