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. Answers and rubric weights stay protected in the interactive flow.
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.