Nested Workflows

import asyncio
from definable.agent import Agent
from definable.agent.workflow import Workflow, Step, Parallel, Condition, Loop

web_researcher = Agent(model="gpt-4o", instructions="Research the web for current information.")
paper_reader = Agent(model="gpt-4o", instructions="Find and summarize academic papers.")
writer = Agent(model="gpt-4o", instructions="Write a comprehensive article from research.")
reviewer = Agent(model="gpt-4o", instructions="Review for accuracy. End with APPROVED or NEEDS_REVISION.")
publisher = Agent(model="gpt-4o", instructions="Format the approved article for publication.")

workflow = Workflow(
    name="full-pipeline",
    steps=[
        # Step 1: Research in parallel
        Parallel(name="research", steps=[
            Step(name="web", agent=web_researcher),
            Step(name="papers", agent=paper_reader),
        ]),
        # Step 2: Write article
        Step(name="write", agent=writer),
        # Step 3: Review and revise
        Loop(
            name="review-loop",
            steps=[
                Step(name="review", agent=reviewer),
                Condition(
                    name="quality-gate",
                    condition=lambda ctx: "APPROVED" in (ctx.get_last_step_content() or ""),
                    true_steps=Step(name="publish", agent=publisher),
                    false_steps=Step(name="rewrite", agent=writer),
                ),
            ],
            end_condition=lambda outputs: any("APPROVED" in (o.content or "") for o in outputs),
            max_iterations=3,
        ),
    ],
)

async def main():
    result = await workflow.arun("Write about breakthroughs in quantum computing in 2026")
    print(result.content)

asyncio.run(main())