---
title: Function Examples
sidebar_position: 3
description: This guide provides detailed instructions for including function examples in the router endpoints of the OpenBB Platform.
keywords:
- OpenBB community
- OpenBB Platform
- Custom commands
- API
- Python Interface
- Examples
- Usage
- Parameters
- contributing
- requirements
---

import HeadTitle from '@site/src/components/General/HeadTitle.tsx';

<HeadTitle title="Function Examples - Contributing - Development | OpenBB Platform Docs" />

Usage examples are defined in the router and are expected to provide working syntax,
with descriptions for complex functions requiring many parameters.

> When a given provider is not installed, its example will be excluded from `openapi.json` and Python docstrings

## Requirements

All router endpoints must have examples.

- If any endpoint is excluded from the schema it only needs to contain a Python example.
- POST method examples should have both API and Python examples, unless they are excluded from the schema.

**For API Examples:**

- At least one example using all required parameters. It cannot use any provider-specific parameters here. It should not specify the provider field.
- If there are more than three parameters, a description must be supplied in the example.

**For Python Examples:**

- Descriptions are mandatory.


## Example Models

There are two models for defining examples, `APIEx` and `PythonEx`. `APIEx` is more structured aiming to be language agnostic - provide less freedom - while `PythonEx` gives more freedom to create complex examples.

```python
from openbb_core.app.model.example import APIEx, PythonEx
```

### `APIEx`

```python
@router.command(
    model="WorldNews",
    examples=[
        APIEx(parameters={}),
        APIEx(parameters={"limit": 100}),
        APIEx(
            description="Get news on the specified dates.",
            parameters={"start_date": "2024-02-01", "end_date": "2024-02-07"},
        ),
        APIEx(
            description="Display the headlines of the news.",
            parameters={"display": "headline", "provider": "benzinga"},
        ),
        APIEx(
            description="Get news by topics.",
            parameters={"topics": "finance", "provider": "benzinga"},
        ),
        APIEx(
            description="Get news by source using 'tingo' as provider.",
            parameters={"provider": "tiingo", "source": "bloomberg"},
        ),
        APIEx(
            description="Filter aticles by term using 'biztoc' as provider.",
            parameters={"provider": "biztoc", "term": "apple"},
        ),
    ],
)
```

### `PythonEx`

```python
@router.command(
    methods=["POST"],
    include_in_schema=False,
    examples=[
        PythonEx(
            description="Perform Ordinary Least Squares (OLS) regression.",
            code=[
                "stock_data = obb.equity.price.historical(symbol='TSLA', start_date='2023-01-01', provider='fmp').to_df()",
                'obb.econometrics.ols_regression(data=stock_data, y_column="close", x_columns=["open", "high", "low"])',
            ],
        )
    ],
)
```