Prevent the Wrong-Account Payment
Redesign the action boundary to prevent wrong-account payment while preserving a legitimate supplier-change route.
19 minutes
Scenario
Keystone Services uses an AI assistant to draft supplier-payment instructions. Two drafts used old bank details from attachments instead of the verified supplier master.
- Your role
- Finance-process owner
- Method
- Mistake Proofing
Evidence pack
Source
The assistant can read email, attachments and the supplier master.
Interface
Amount and narrative are prominent; destination is collapsed by default.
Permission
One service account drafts and submits payment instructions.
Duplicates
A retry after timeout can create a second pending instruction.
Changes
About 2% of suppliers legitimately request bank-detail changes monthly.
Current control
Reviewers see a warning: Check all payment details before approval.
Recovery
Pending instructions can be cancelled for fifteen minutes; this is not shown in the review screen.
Audit
The log records final submission but not source, validation or override evidence.
Constraints
- The assistant may not modify the supplier master.
- Bank-detail changes require independent verification by an authorised role.
- The design must support urgent but legitimate payments without informal bypass.
Case steps
Work through each prompt using the evidence pack. These guided cases support self-directed practice; server-scored attempts are not available yet.
Define intended condition, mistake, defect and effect using e1-e8.
Design two prevention mechanisms stronger than the current warning.
Design an accountable bank-change exception route and a safe recovery path.
Define boundary tests and measures for the redesigned control.