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

# Step Choices Parameter

> Demonstrates using `step_choices` in a router selector for dynamic step selection.

```python step_choices_parameter.py theme={null}
"""
Step Choices Parameter
======================

Demonstrates using `step_choices` in a router selector for dynamic step selection.
"""

from typing import List, Union

from agno.agent.agent import Agent
from agno.models.openai import OpenAIChat
from agno.workflow.router import Router
from agno.workflow.step import Step
from agno.workflow.types import StepInput
from agno.workflow.workflow import Workflow

# ---------------------------------------------------------------------------
# Create Agents
# ---------------------------------------------------------------------------
researcher = Agent(
    name="researcher",
    model=OpenAIChat(id="gpt-4o-mini"),
    instructions="You are a researcher.",
)

writer = Agent(
    name="writer",
    model=OpenAIChat(id="gpt-4o-mini"),
    instructions="You are a writer.",
)

reviewer = Agent(
    name="reviewer",
    model=OpenAIChat(id="gpt-4o-mini"),
    instructions="You are a reviewer.",
)


# ---------------------------------------------------------------------------
# Define Router Selector
# ---------------------------------------------------------------------------
def dynamic_selector(
    step_input: StepInput,
    step_choices: list,
) -> Union[str, Step, List[Step]]:
    user_input = step_input.input.lower()
    step_map = {s.name: s for s in step_choices if hasattr(s, "name") and s.name}

    print(f"Available steps: {list(step_map.keys())}")

    if "research" in user_input:
        return "researcher"
    if "write" in user_input:
        return step_map.get("writer", step_choices[0])
    if "full" in user_input:
        return [step_map["researcher"], step_map["writer"], step_map["reviewer"]]
    return step_choices[0]


# ---------------------------------------------------------------------------
# Create Workflow
# ---------------------------------------------------------------------------
workflow = Workflow(
    name="Dynamic Routing (step_choices)",
    steps=[
        Router(
            name="Dynamic Router",
            selector=dynamic_selector,
            choices=[researcher, writer, reviewer],
        ),
    ],
)

# ---------------------------------------------------------------------------
# Run Workflow
# ---------------------------------------------------------------------------
if __name__ == "__main__":
    workflow.print_response("I need to research something", stream=True)
```

## Run the Example

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

  <Step title="Install dependencies">
    ```bash theme={null}
    uv pip install -U agno cel-python fastapi 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 `step_choices_parameter.py`, then run:

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

Full source: [cookbook/04\_workflows/05\_conditional\_branching/step\_choices\_parameter.py](https://github.com/agno-agi/agno/blob/main/cookbook/04_workflows/05_conditional_branching/step_choices_parameter.py)