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"""
Router With Loop
================

Demonstrates router-based selection between simple web research and iterative loop-based deep tech research.
"""

import asyncio
from typing import List

from agno.agent.agent import Agent
from agno.tools.hackernews import HackerNewsTools
from agno.tools.websearch import WebSearchTools
from agno.workflow.loop import Loop
from agno.workflow.router import Router
from agno.workflow.step import Step
from agno.workflow.types import StepInput, StepOutput
from agno.workflow.workflow import Workflow

# ---------------------------------------------------------------------------
# Create Agents
# ---------------------------------------------------------------------------
hackernews_agent = Agent(
    name="HackerNews Researcher",
    instructions="You are a researcher specializing in finding the latest tech news and discussions from Hacker News. Focus on startup trends, programming topics, and tech industry insights.",
    tools=[HackerNewsTools()],
)

web_agent = Agent(
    name="Web Researcher",
    instructions="You are a comprehensive web researcher. Search across multiple sources including news sites, blogs, and official documentation to gather detailed information.",
    tools=[WebSearchTools()],
)

content_agent = Agent(
    name="Content Publisher",
    instructions="You are a content creator who takes research data and creates engaging, well-structured articles. Format the content with proper headings, bullet points, and clear conclusions.",
)

# ---------------------------------------------------------------------------
# Define Steps
# ---------------------------------------------------------------------------
research_hackernews = Step(
    name="research_hackernews",
    agent=hackernews_agent,
    description="Research latest tech trends from Hacker News",
)

research_web = Step(
    name="research_web",
    agent=web_agent,
    description="Comprehensive web research on the topic",
)

publish_content = Step(
    name="publish_content",
    agent=content_agent,
    description="Create and format final content for publication",
)


# ---------------------------------------------------------------------------
# Define Loop Evaluator
# ---------------------------------------------------------------------------
def research_quality_check(outputs: List[StepOutput]) -> bool:
    if not outputs:
        return False

    for output in outputs:
        if output.content and len(output.content) > 300:
            print(
                f"[PASS] Research quality check passed - found substantial content ({len(output.content)} chars)"
            )
            return True

    print("[FAIL] Research quality check failed - need more substantial research")
    return False


# ---------------------------------------------------------------------------
# Define Loop And Router
# ---------------------------------------------------------------------------
deep_tech_research_loop = Loop(
    name="Deep Tech Research Loop",
    steps=[research_hackernews],
    end_condition=research_quality_check,
    max_iterations=3,
    description="Perform iterative deep research on tech topics",
)


def research_strategy_router(step_input: StepInput) -> List[Step]:
    topic = step_input.previous_step_content or step_input.input or ""
    topic = topic.lower()

    deep_tech_keywords = [
        "startup trends",
        "ai developments",
        "machine learning research",
        "programming languages",
        "developer tools",
        "silicon valley",
        "venture capital",
        "cryptocurrency analysis",
        "blockchain technology",
        "open source projects",
        "github trends",
        "tech industry",
        "software engineering",
    ]

    if any(keyword in topic for keyword in deep_tech_keywords) or (
        "tech" in topic and len(topic.split()) > 3
    ):
        print(f"Deep tech topic detected: Using iterative research loop for '{topic}'")
        return [deep_tech_research_loop]

    print(f"Simple topic detected: Using basic web research for '{topic}'")
    return [research_web]


# ---------------------------------------------------------------------------
# Create Workflow
# ---------------------------------------------------------------------------
workflow = Workflow(
    name="Adaptive Research Workflow",
    description="Intelligently selects between simple web research or deep iterative tech research based on topic complexity",
    steps=[
        Router(
            name="research_strategy_router",
            selector=research_strategy_router,
            choices=[research_web, deep_tech_research_loop],
            description="Chooses between simple web research or deep tech research loop",
        ),
        publish_content,
    ],
)

# ---------------------------------------------------------------------------
# Run Workflow
# ---------------------------------------------------------------------------
if __name__ == "__main__":
    print("=== Testing with deep tech topic ===")
    workflow.print_response(
        "Latest developments in artificial intelligence and machine learning and deep tech research trends"
    )

    asyncio.run(
        workflow.aprint_response(
            "Latest developments in artificial intelligence and machine learning and deep tech research trends"
        )
    )

​
Run the Example

# Clone and setup repo
git clone https://github.com/agno-agi/agno.git
cd agno/cookbook/04_workflows/05_conditional_branching

# Create and activate virtual environment
./scripts/demo_setup.sh
source .venvs/demo/bin/activate

python router_with_loop.py