criticalP1

Silent quality regression — refund verification skipped after model downgrade (gpt-oss-20b)

Open· quality· First seen 7/1/2026, 9:59:59 AM
Where
Acme Corp/Production/checkout-bot/checkout-planner

What / Why

checkout-planner was switched from claude-3-5-sonnet-20241022 to gpt-oss-20b on May 26 to reduce inference cost. The smaller model silently omits the verify_refund step. Refunds are issuing without validation. No errors, normal latency — agent self-reports success on all affected runs. ~29% failure rate detected by RouteIQ quality checks.

Actions

Cost Savings

$211.00

$0.008/run × 180 runs/hr × 46h ≈ $211

Cost/run

$0.008

Runs/hr

180

Hrs to catch

46h

Interventions (1)

WhenActionByReasonPrevented $
7/3/2026deploy_rollbackusr_demoRolled back to claude-3-5-sonnet-20241022 (v1.3.1) — gpt-oss-20b confirmed as cause of silent quality regression$211.00

Audit Trail

alert.openby usr_demo7/1/2026, 9:59:59 AM

{"severity":"p1"}

alert.resolveby usr_demo7/3/2026, 6:29:59 AM

{"resolution":"model_rollback_deployed"}