Trace refund approval flows with OpenRouter and OpenTelemetry

Description

Quick overview
This workflow enriches a refund request, drafts an approval proposal with an AI agent, and waits for a human decision, so you can follow one execution across the wait with OpenTelemetry tracing. It is Exercise 5 from the n8n Production AI Playbook on Audit & Trace.

How it works
Receives a POST webhook request with a requestId, amount in cents, reason and a traceparent header.
Enrich Request Sub-workflow validates the request and adds simulated customer context.
Policy Service Call sends an HTTP request that carries the trace context to an echo service.
Approval Proposal Agent drafts a proposal using an OpenRouter chat model.
Return Approval Request responds with the proposal, executionId and resumeUrl.
Wait for Human Approval pauses until a decision is posted to the resume URL.
Validate Approval checks the decision and Record Approval saves it. Invalid decisions stop at Reject Approval.

Setup
Import, save and publish the Exercise 5 enrichment sub-workflow, then select it in Enrich Request Sub-workflow.
Add an OpenRouter API credential to OpenRouter - Approval.
Optionally enable OpenTelemetry tracing in Settings > OpenTelemetry.
Select Execute workflow and POST {"requestId":"REQ-2001","amount":4999,"reason":"duplicate charge"} with a traceparent header.
POST {"approved":true,"approver":"Demo reviewer"} to the returned resumeUrl, then search your traces by n8n.execution.id to find both parts of the run.

Requirements
n8n Cloud or a self-hosted n8n instance
An OpenRouter API key
The Exercise 5 enrichment sub-workflow
A trace viewer such as Jaeger to inspect the spans (optional)

Customization
Replace Policy Service Call with a call to your own instrumented service so its spans join the same trace.

Additional info
No payment is processed. The approver field is a demo value. In production, take the reviewer's identity from an authenticated login and protect the resume endpoint.