> ## Documentation Index
> Fetch the complete documentation index at: https://agno-v2-docs-scavio-google-v2.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Chat Agent Flex Tier

> Run o4-mini on the flex service tier by setting service_tier on OpenAIChat.

```python agent_flex_tier.py theme={null}
"""
Openai Agent Flex Tier
======================

Cookbook example for `openai/chat/agent_flex_tier.py`.
"""

from agno.agent import Agent
from agno.models.openai import OpenAIChat

# ---------------------------------------------------------------------------
# Create Agent
# ---------------------------------------------------------------------------

agent = Agent(
    model=OpenAIChat(id="o4-mini", service_tier="flex"),
    markdown=True,
)

agent.print_response("Share a 2 sentence horror story")

# ---------------------------------------------------------------------------
# Run Agent
# ---------------------------------------------------------------------------

if __name__ == "__main__":
    pass
```

## Run the Example

<Steps>
  <Snippet file="create-venv-step.mdx" />

  <Step title="Install dependencies">
    ```bash theme={null}
    uv pip install -U agno openai
    ```
  </Step>

  <Step title="Export your OpenAI API key">
    <CodeGroup>
      ```bash Mac/Linux theme={null}
      export OPENAI_API_KEY="your_openai_api_key_here"
      ```

      ```bash Windows theme={null}
      $Env:OPENAI_API_KEY="your_openai_api_key_here"
      ```
    </CodeGroup>
  </Step>

  <Step title="Run the example">
    Save the code above as `agent_flex_tier.py`, then run:

    ```bash theme={null}
    python agent_flex_tier.py
    ```
  </Step>
</Steps>

Full source: [cookbook/90\_models/openai/chat/agent\_flex\_tier.py](https://github.com/agno-agi/agno/blob/main/cookbook/90_models/openai/chat/agent_flex_tier.py)