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

# Functions

Any python function can be used as a tool by an Agent. **We highly recommend** creating functions specific to your workflow and adding them to your Agents.

For example, here's how to use a `get_top_hackernews_stories` function as a tool:

```python hn_agent.py theme={null}
import json
import httpx

from phi.agent import Agent


def get_top_hackernews_stories(num_stories: int = 10) -> str:
    """Use this function to get top stories from Hacker News.

    Args:
        num_stories (int): Number of stories to return. Defaults to 10.

    Returns:
        str: JSON string of top stories.
    """

    # Fetch top story IDs
    response = httpx.get('https://hacker-news.firebaseio.com/v0/topstories.json')
    story_ids = response.json()

    # Fetch story details
    stories = []
    for story_id in story_ids[:num_stories]:
        story_response = httpx.get(f'https://hacker-news.firebaseio.com/v0/item/{story_id}.json')
        story = story_response.json()
        if "text" in story:
            story.pop("text", None)
        stories.append(story)
    return json.dumps(stories)

agent = Agent(tools=[get_top_hackernews_stories], show_tool_calls=True, markdown=True)
agent.print_response("Summarize the top 5 stories on hackernews?", stream=True)
```