We're going to need default hard budget caps on pretty much everything

A soft spending cap is just an email telling you that you already owe the money. Simon Willison’s argument: hard caps that return errors should be the default, with unlimited spend hidden behind an opt-out checkbox. AWS only shipped monthly spend limits in September (project paused once you hit it), Google Cloud added Spend Caps in July. It took coding agents deploying real infrastructure to make this urgent.