The following code present in my controller file generated by phx.gen.html call for clarity on the intended usage of context and schema.

  def index(conn, _params) do
    invoices = Billing.list_invoices()
    render(conn, "index.html", invoices: invoices)
  end

  def new(conn, _params) do
    changeset = Billing.change_invoice(%InvoiceApplication.Billing.Invoice{})
    render(conn, "new.html", changeset: changeset)
  end

Except for the new action, where the schema %InvoiceApplication.Billing.Invoice{} is used, no part of the controller directly calls the schema. If the intention of context module is to provide public apis and hide the implementation details such as the schema name, phx.gen.html should generate a controller without specifying schema names such as Billing.new_invoice/0 or Billing.build_invoice/0.

So the clarity needed is do we expose schema outside the context or not? If we do expose them, then clearly context file is not the only public api of a context.