Trigger sync via Kubernetes API

[vonbox]

I have ArgoCD running in a Kubernetes cluster and I want to trigger an Application sync from within a pod. If I can do that via the Kubernetes API, by POSTing or PUTting something to an Application resource, I would not need to worry about authenticating to the ArgoCD API. Is that possible.
In other words; when the ArgoCD API server receives a request to do a sync, does is handle that by calling the Kubernetes API server to update the state of the Application resource, or does it somehow give the Application controller a direct instruction. If the first, what does that update look like?