Northvale Mortgage Assistant

Context

Northvale had a mortgage assistant that tested well in a pilot of 2,000 customers. Model risk would not approve a wider launch without evidence of how it behaved on edge cases: arrears, vulnerable customers and rate questions it must never answer as advice.

Approach

We connected the Signa SDK in a day and captured two weeks of real traffic in shadow mode. From those traces the team built a graded suite of edge cases with their own subject-matter experts, then set release thresholds for each one.

Guardrails ran in monitor mode for a fortnight before switching to enforce, so every block was tuned on real conversations rather than guesses.

Result

A retail bank moved its mortgage assistant from pilot to 1.2M customers with a full audit trail in six weeks. The full evidence pack — tests, thresholds, incidents and sign-offs — is regenerated on every release.