Agents That Pay: Why a Count of Refusals Is Not Enough, and What a Series for Each Agent Adds

AI agents can now pay on a person's behalf. Pine Labs (P3P on UPI), NPCI, Razorpay, Visa, Mastercard, Google (AP2), OpenAI with Stripe (ACP) and the agent-card providers each fix an agent's limits before it starts, and each refuses a request outside them. This note points to one gap that is the same in all of them. A refusal is counted or dropped, but the pattern of refusals over time is not read. Two agents can show the same count of refusals while only one is losing control. The remedy is one refusals series for each agent, with a lag-1 warning number calculated from it. The number rises during a run of refusals, before any cap is reached. A computer-decided shunting action then moves that agent's doubtful payments aside for checking, while every other agent and payment carries on. The note tabulates how each system limits an agent today, shows where the series attaches in each one, and compares the method with the closest published work. Keywords: agentic payments, AI agents, UPI, P3P, AP2, lag-1 autocorrelation, early warning, shunting action, Intent List