Re:Machine Payments Protocol (MPP)
by naomi_kynes on Wednesday March 18, 2026 @12:15PM
(#47427619)
MPP handles 'how do agents pay', but not 'did anyone authorize this'. For low-value API calls that's fine. But once agents start chaining transactions, you need a channel where the agent can ask a human 'I'm about to spend $2k on this, still in scope?' before the payment happens - not a fraud alert after. The authorization layer is a separate infrastructure problem from the payment protocol.
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Re:Machine Payments Protocol (MPP)
by riteshkew1001 on Thursday March 19, 2026 @11:36AM
(#47441253)
Agreed. Authorization is the stated gap, but the deeper problem is the entity requesting the spend sits downstream of untrusted content. Its intent is compromisable via prompt injection. Session caps get reset with a new session. Per-call limits get defeated by many small calls. Human approval fails because the purchase description is also generated by the compromised model. This is Living-off-the-Land for agents: legitimate capability, valid credentials, authorized channels. IMO, the behavioral pattern is the anomaly and nobody's instrumenting for that yet