May 2026 was the month core banking providers started shipping AI agents. On 4 May FIS announced it is building a Financial Crimes AI Agent with Anthropic, designed to assemble evidence across a bank's core systems, evaluate activity against known typologies and draft suspicious activity report narratives, with investigators keeping control of every decision[1]. BMO and Amalgamated Bank are among the first institutions developing with it, with general availability planned for the second half of 2026. Ten days later Fiserv launched agentOS, a platform to run its own and partners' agents across its core, payments and servicing systems[2].
Both providers put governance at the centre. FIS says every agent decision is traceable and auditable and client data stays within its controlled infrastructure; Fiserv lists identity-bound execution, policy enforcement and human oversight.
Vendor governance is necessary, but it is not the bank's governance. When an agent reads customer data, assembles an AML case or prepares a lending decision, the bank remains accountable to its supervisor for the outcome. The five checks below are what I would complete before any vendor-supplied agent touches a regulated process. They take weeks, not months, and they make the difference between an agent you can defend and one you have to explain.
