Router

Classify input → dispatch to one specialist Agent. OpenAI Agents SDK March 2026 “Handoff” pattern, plus the classify-and-route shape every framework reinvents (CrewAI sequential, LangGraph conditional edges).


                       ┌── refund_agent
   prompt ──► classifier ──► technical_agent      ◄── only ONE
                       └── faq_agent ◄── chosen      runs

   1 classifier call + 1 specialist run.

Pattern

Classify. A small fast LLM call decides which route handles the input best.
Dispatch. The chosen specialist Agent runs to completion with its own model / memory / tools / architecture.
Return. The specialist’s output becomes the Router’s output. No cross-specialist synthesis.

Compared to Supervisor

Cheaper. 1 Classification + 1 specialist; no synthesis pass.
Deterministic. Single specialist owns the task end-to-end.
Less flexible. No multi-domain tasks; routing errors cascade.

Usage


from loomflow import Agent
from loomflow.architecture import RouterRoute
from loomflow.team import Team
 
billing = Agent("Handle billing questions.", model="claude-opus-4-7", tools=[...])
tech    = Agent("Handle technical questions.", model="claude-opus-4-7", tools=[...])
sales   = Agent("Handle sales questions.", model="claude-opus-4-7")
 
team = Team.router(
    routes=[
        RouterRoute(name="billing", agent=billing,
                    description="Charges, refunds, invoicing, plan changes."),
        RouterRoute(name="tech", agent=tech,
                    description="Errors, debugging, integration help."),
        RouterRoute(name="sales", agent=sales,
                    description="Pricing, demos, contracts, partnerships."),
    ],
    instructions="You are the customer support entry point.",
    model="claude-haiku-4-5",   # small fast classifier
)
 
result = await team.run("My credit card was charged twice.")
# Routed to billing.

When to use

Customer support. Route to billing / tech / sales / general.
Coding agent gateway. Route to language-specific specialists.
Search front-end. Route between retrieval strategies.

The classifier is the cost knob. Use a small fast model (Haiku, gpt-4o-mini) for the classifier and reserve the big model for specialists.

RouterRoute descriptions are the prompt. The classifier sees each route’s name + description; the description is what makes routing correct or wrong. Be specific about what each route handles AND what it doesn’t (e.g. “Handle billing. NOT refunds, those go to support”).