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

# OpenAI Reasoning Model GPT 4 1

> Use GPT-4.1 as the reasoning model behind a GPT-4o-mini agent via the Responses API.

```python reasoning_model_gpt_4_1.py theme={null}
"""
Reasoning Model Gpt 4 1
=======================

Demonstrates this reasoning cookbook example.
"""

from agno.agent import Agent
from agno.models.openai.responses import OpenAIResponses


# ---------------------------------------------------------------------------
# Create Example
# ---------------------------------------------------------------------------
def run_example() -> None:
    agent = Agent(
        model=OpenAIResponses(id="gpt-5.6-luna"),
        reasoning_model=OpenAIResponses(id="gpt-4.1"),
    )
    agent.print_response(
        "Solve the trolley problem. Evaluate multiple ethical frameworks. "
        "Include an ASCII diagram of your solution.",
        stream=True,
    )


# ---------------------------------------------------------------------------
# Run Example
# ---------------------------------------------------------------------------
if __name__ == "__main__":
    run_example()
```

## Run the Example

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

**1. Install dependencies**

```bash theme={null}
uv pip install -U agno openai
```

**2. Export your OpenAI API key**

```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"
```

**3. Run the example**

Save the code above as `reasoning_model_gpt_4_1.py`, then run:

```bash theme={null}
python reasoning_model_gpt_4_1.py
```

Full source: [cookbook/10\_reasoning/models/openai/reasoning\_model\_gpt\_4\_1.py](https://github.com/agno-agi/agno/blob/v3.0.4/cookbook/10_reasoning/models/openai/reasoning_model_gpt_4_1.py)


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