# Prerequisites

WARNING: The Assistants API is deprecated and will be shut down.
For more information see the OpenAI documentation: https://platform.openai.com/docs/assistants/migration

Before you begin, ensure you have the following prerequisites:

- .NET 10 SDK or later
- OpenAI API key

Set the following environment variables:

```powershell
$env:OPENAI_API_KEY="*****" # Replace with your OpenAI API key
$env:OPENAI_MODEL="gpt-4o-mini"  # Optional, defaults to gpt-4o-mini
```