https://notes.karlmcguinness.com/series/what-the-corporate-card-already-solved/Recent content in What the Corporate Card Already Solved on Control Plane by Karl McGuinnessHugoen-uspublic@karlmcguinness.com (Karl McGuinness)public@karlmcguinness.com (Karl McGuinness)Fri, 05 Jun 2026 13:00:00 -0700https://notes.karlmcguinness.com/notes/canceling-the-card-doesnt-stop-the-charges/Fri, 05 Jun 2026 13:00:00 -0700public@karlmcguinness.com (Karl McGuinness)https://notes.karlmcguinness.com/notes/canceling-the-card-doesnt-stop-the-charges/Cancel a card and watch what refuses to end: the subscription bills the new number the network helpfully forwarded, the pending hotel charge settles days later, and the refund arrives through a process you do not control. Payments learned that ending an instrument is not ending an arrangement, and built machinery for the difference: reversible freezes, terminal cancellations, single-use cards that retire themselves, in-flight states between authorized and settled, chargebacks as governed compensation, and the statement that reconciles everything to one project code. This post maps each ending onto the agent task that must actually stop, and closes with the breaks, including the one where the analogy runs backward.https://notes.karlmcguinness.com/notes/the-network-approves-every-transaction/Fri, 05 Jun 2026 12:00:00 -0700public@karlmcguinness.com (Karl McGuinness)https://notes.karlmcguinness.com/notes/the-network-approves-every-transaction/A decline at the register is mild embarrassment and a tap of a different card, because the system is working: the network approves transactions, not cards. This post walks per-action authorization the way payments runs it: the plastic that proves almost nothing, the authorization that binds this amount at this merchant now, the hotel hold that expires, the freeze that declines the next swipe wherever the issuer decision is checked, and the ATM, the escape hatch every honest card program names in writing. Then the breaks: agents have no common payment-style network, their false-approval costs are unbounded, and their cardholder can be hypnotized mid-purchase.https://notes.karlmcguinness.com/notes/the-contractor-gets-their-own-card/Fri, 05 Jun 2026 11:00:00 -0700public@karlmcguinness.com (Karl McGuinness)https://notes.karlmcguinness.com/notes/the-contractor-gets-their-own-card/Crunch week. The contractor needs materials, and the project manager hands over her own card, just this once. Everything about it is convenient and everything about it is wrong, and every finance team knows exactly why. This post walks delegation the way a mature card program runs it: the contractor’s own card with a lower limit, attribution that survives the handoff, cards that die when the project closes, and caps on how many cards a project may issue, not just how big each one is. Then the three places the analogy breaks for AI agents, where the fixes have to be built.https://notes.karlmcguinness.com/notes/you-approve-what-you-were-shown/Fri, 05 Jun 2026 10:00:00 -0700public@karlmcguinness.com (Karl McGuinness)https://notes.karlmcguinness.com/notes/you-approve-what-you-were-shown/A manager approves a conference request on their phone between meetings. Months later, the only defensible answer to ‘what did you approve?’ is the request as rendered on that screen. This post walks the anatomy of a real approval: requests that are proposals and nothing more, reviewers who narrow instead of denying, decisions that take days without losing their place, and the disclosure that binds. Payments turned that last idea into regulation. Then the honest part: three places the analogy breaks for AI agents, and what each break demands.https://notes.karlmcguinness.com/notes/agents-need-a-corporate-card-not-a-blank-check/Fri, 05 Jun 2026 09:00:00 -0700public@karlmcguinness.com (Karl McGuinness)https://notes.karlmcguinness.com/notes/agents-need-a-corporate-card-not-a-blank-check/Nobody hands a new hire the company checkbook. In a mature spend program, they get an instrument bound to an approved purpose, checked at each transaction, metered against a budget, and frozen when the reason for the spend goes away. Agent credentials today are blank checks with expiry dates. This post walks the expense-governance loop end to end, maps each control onto agent authority, and is honest about the five places the analogy breaks. Each break is something the agent stack still has to build.