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

# Extension Attributes

[Custom extensions](/reference/dmn/custom-extensions) are a standardized way to extend the DMN model.
The [ASEE Flow extension attributes](/reference/dmn/custom-extensions/camunda-attributes) are fully implemented in the DMN model API.

Every DMN `Decision` element can have the attributes `historyTimeToLive` and `versionTag`.
To access the extension attributes, you have to call the `Decision#getCamundaHistoryTimeToLiveString()` and
`Decision#getVersionTag()` methods.

```java theme={null}
String historyTimeToLive = decision.getCamundaHistoryTimeToLiveString();
String versionTag = decision.getVersionTag();
```

To set attributes, use `Decision#setCamundaHistoryTimeToLiveString()` and `Decision#setVersionTag()`

```java theme={null}
decision.setCamundaHistoryTimeToLiveString("1000");
decision.setVersionTag("1.0.0");
```

Every `Input` element can have an `inputVariable` attribute.
This attribute specifies the variable name which can be used to access the result of the input expression in an input entry expression.
It can be set and fetched similarly, calling `Input#setCamundaInputVariable()` and `Input#getCamundaInputVariable()`:

```java theme={null}
input.setCamundaInputVariable("camundaInput");
String camundaInput = input.getCamundaInputVariable();
```