***

title: purpose
slug: /reference/python/agents/data-map/purpose
description: Set the function description shown to the AI.
max-toc-depth: 3
---------------------

For a complete index of all SignalWire documentation pages, fetch https://signalwire.com/docs/llms.txt

[ref-datamap]: /docs/server-sdks/reference/python/agents/data-map

[description]: /docs/server-sdks/reference/python/agents/data-map/description

Set the function description shown to the AI when deciding which tool to call.
[`description()`][description] is an alias for this method.

## **Parameters**

<ParamField path="description" type="str" required={true} toc={true}>
  Human-readable description of what this function does.
</ParamField>

## **Returns**

[`DataMap`][ref-datamap] -- Self for method chaining.

## **Example**

```python {4}
from signalwire import DataMap

weather = DataMap("get_weather")
weather.purpose("Get the current weather for a given city")
```