Dev Tools · 7h ago
Spend Cap Flaw: Free Fallback Equals Fail-Open in AI Cost Control
A developer demonstrates that a spend cap using a free local model as fallback produces identical decision streams to a fail-open policy, both charging zero. The hash collision proves the two strategies are indistinguishable in ledger terms, despite different branding. The real issue is whether the ledger keeps moving during oracle outages, not the fail-open vs fail-closed framing.
Meridian48 take
The post exposes a subtle but critical design flaw in AI spend caps, where well-intentioned fallbacks can silently undermine budget controls.
ai-cost-controlspend-cap-design