01
Find the order
A tool loads order #4831 from the application service.
Everyday workflow / Refund review
An agent recommends. A person decides.
A support agent loads order #4831, checks the return policy, streams a typed recommendation, and waits for approval before it issues the refund.
Read interrupts and resumeRefund request #4831
MAYA LOPEZ · 12 DAYS SINCE DELIVERY
Customer message
“I received the US keyboard layout instead of the Spanish one. The box is still sealed. Can I get a refund?”
Order total$84.00
ConditionUnopened
Agent recommendation
Eligible for a full refund
The request is inside the 30-day window and the item is unopened. Refund to the original payment method.
Issue $84.00 refund?
ApproveEscalate
What happens in the runtime
A refund passes through five named steps.
02
Check policy
A focused node compares delivery date, condition, and return rules.
03
Draft decision
useReason streams a schema-validated recommendation into React.
04
Ask a person
The run checkpoints before money moves or product data changes.
05
Resume and refund
The approved run continues once and records the final outcome.
Human input in one node
The external write happens after approval.
Resume replays node code from a checkpoint. Keep side effects after the interrupt or protect them with an idempotency key. useInterrupt marks that checkpoint in the node.
approve-refund.node.ts
// approve-refund.node.ts
const action = await useInterrupt({
id: "refund-approval",
request: {
kind: "choice",
question: "Issue the $84 refund?",
options: [approve, escalate],
},
});
return {
condition: action,
data: { orderId, action },
};Runtime events in the interface
React renders the state of the active run.
Tools
Load the order through request-scoped tools or an application service.
Typed output
Validate the recommendation before it appears as product state.
Interrupts
Tie the approval control to the exact checkpoint and request.
Side effects
Issue the refund after the resumed run reaches the write node.
Session history
Rollback and fork the server workflow together with the visible messages.
Larger open-source example
Canvas adds custom pickers, structured editors, and routing across several workflows.
Replace the refund policy with one of your own.
Connect your services to the same workflow, interrupt, and resume APIs used in this example.