How can I access the api@internal service from within the cluster

I guess I found the solution

with api.insecure=true and not having a endpoint called traefik, api is available on port 8080 for which I can create a service object

Doc: Traefik API Documentation - Traefik

apiVersion: v1
kind: Service
metadata:
  name: service-traefik-api
  namespace: prod-xxx
spec:
  selector:
    app: deployment-traefik
  ports:
    - name: api-http-internal
      protocol: TCP
      port: 80
      targetPort: 8080

which can be accessed from within the cluster as curl http://service-traefik-api/api/overview