Simon Willison

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

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Simon Willison argues that pay‑by‑usage services and APIs should implement default hard budget caps that stop usage and return errors once a set monthly limit is reached, rather than merely sending warning emails. He contends that coding agents and personal agents often trigger costly API calls, and hard caps prevent unexpected large bills. Willison calls for a clear opt‑in checkbox to remove the cap, and notes that AWS has recently introduced spending limits to address this issue.

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