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

# Nested Workflow with Condition

> Inner workflow with a `Condition` step for conditional fact-checking before passing results to the outer workflow.

```python theme={null}
from agno.agent import Agent
from agno.models.openai import OpenAIChat
from agno.workflow import Condition
from agno.workflow.step import Step
from agno.workflow.types import StepInput, StepOutput
from agno.workflow.workflow import Workflow


def needs_fact_check(step_input: StepInput) -> bool:
    """Check if the previous step's content mentions statistics or numbers."""
    prev = step_input.previous_step_content or ""
    return any(char.isdigit() for char in prev)


def format_for_writer(step_input: StepInput) -> StepOutput:
    prev = step_input.previous_step_content or step_input.input
    return StepOutput(content=prev)


# Inner workflow: research with conditional fact-checking
researcher = Agent(
    name="Researcher",
    model=OpenAIChat(id="gpt-4o-mini"),
    instructions="Research the topic. Include specific dates and numbers where relevant.",
)

fact_checker = Agent(
    name="Fact Checker",
    model=OpenAIChat(id="gpt-4o-mini"),
    instructions="Verify the facts in the provided text. Correct any inaccuracies.",
)

inner_workflow = Workflow(
    name="Research with Fact Check",
    description="Researches a topic and conditionally fact-checks the results",
    steps=[
        Step(name="research", agent=researcher),
        Condition(
            name="fact_check_gate",
            description="Fact-check if content contains numbers",
            evaluator=needs_fact_check,
            steps=[Step(name="fact_check", agent=fact_checker)],
            else_steps=[Step(name="pass_through", executor=format_for_writer)],
        ),
    ],
)

# Outer workflow
writer = Agent(
    name="Writer",
    model=OpenAIChat(id="gpt-4o-mini"),
    instructions="Write a polished paragraph from the research provided.",
)

outer_workflow = Workflow(
    name="Research, Check, and Write",
    description="Researches, conditionally fact-checks, then writes",
    steps=[
        Step(name="research_phase", workflow=inner_workflow),
        Step(name="writing_phase", agent=writer),
    ],
)


if __name__ == "__main__":
    outer_workflow.print_response(
        input="What are the key milestones in space exploration?",
        stream=True,
    )
```

## Run the Example

```bash theme={null}
git clone https://github.com/agno-agi/agno.git
cd agno/cookbook/04_workflows/06_advanced_concepts/workflow_as_a_step

pip install agno openai

python nested_workflow_with_condition.py
```