A formatting rule threatened to block invoices overnight — the fix: retry, invisibly
1 · The constraint
On a date known in advance, the supplementary insurers' interprofessional body tightened its directory rules: only the exact identifier format stored in the database would be accepted. A leading zero or a different length now meant a rejection, for data that had worked the day before. Left alone, a large volume of invoices would have been blocked from day one, with no way for the practitioner to understand why.
My part was design on the only visible piece of the initiative: the override mechanism left to the practitioner. The automatic correction is backend work with no interface; I don't claim it as a design deliverable, but as a decision the team reached together.
2 · The decision: show nothing
The system intercepts the format error, extracts the correct identifier from the error message, corrects it in the patient record and retries the call. The spec says it explicitly: the retry must be invisible to the practitioner. A user should never have to manage an identifier-format problem they didn't cause.
3 · Outcome
Shipped; targets not documented as met — a directory-call success rate above 98%, no rejection regression on switch-over day, no support spike.
There is no screen to show here. The value is the disruption that didn't happen.