In January, three researchers built a shopping agent on Google's Agent Payments Protocol (AP2), the standard designed to make agent-led purchases safe through cryptographically verifiable mandates. Then they attacked it with nothing more exotic than adversarial text. The paper, "Whispers of Wealth" (arXiv 2601.22569, revised May 2026), reports that simple prompt injections reliably subverted the agent: one attack steered which products the agent ranked and bought, another exfiltrated sensitive user data. The part of the stack that failed was not the cryptography. The mandates verified exactly what they were designed to verify. What folded was the layer that exercises judgment.
Hold that result in mind, because the agent economy is currently pouring money into judgment.
Everyone is hiring a referee
Look at what shipped in the last few months for agent-to-agent commerce, and a single pattern repeats: put the money in escrow, and let a judge decide when it comes out.
ERC-8183 formalizes it: funds sit in an escrow contract while an Evaluator - an agent or a human - decides whether the deliverable meets the spec before releasing payment. It is the pattern Virtuals' Agent Commerce Protocol runs on. Circle has piloted an escrow agent for USDC flows. Kustodia and Nava (which raised $8.3M) are startups built on the same shape. And on July 1, BNB Chain and AWS launched agents that bank themselves - agents deployed to Amazon Bedrock AgentCore with their own wallets, identity, and payment stack from birth. Even the category label is contested now: at least one project has declared itself an "MCP Settlement Standard" from a landing page.
