Incident window: Sep 24, 2025, 10:00 AM–3:00 PM PT (≈5 hours)
Maintenance window (completed): Sep 23, 9:00 PM–Sep 24, 2:00 AM PT
Status: Resolved
Surfaces: Web agent, Slack agent, Questionnaires
Trust centers: Not impacted
Summary
Following planned maintenance to implement tenant-level data segregation, the knowledge base (KB) was not bound to individual tenant indices. A validation check incorrectly passed and did not verify KB content/binding, allowing some answers to be generated without tenant facts. This led to degraded quality and hallucinations for a subset of requests.
Impact
- Ungrounded or lower-quality answers for ~5 hours.
- No data loss and no cross-tenant access.
- All affected questionnaires were reprocessed; impacted customers were contacted directly.
Root cause
A migration step omitted rehydrating and binding the KB to per-tenant indices. Validation asserted index availability but did not assert non-empty tenant-scoped content, resulting in a false positive.
Detection
Detected at 10:00 AM PT via a customer report and our existing “answers without facts” alert, after the maintenance had concluded.
Resolution & recovery
- Rebuilt and bound per-tenant KB indices.
- Temporarily blocked ungrounded answering until grounding metrics returned to baseline.
- Reprocessed all affected questionnaires and verified quality.
Preventive actions
- Strengthen validation to require per-tenant existence + non-empty content + correct binding.
- Expand pre- and post-cutover canaries (Web/Slack) to verify grounded answers.
- Add a hard circuit breaker to prevent answering when facts are unavailable.
- Update runbooks and add a dry-run checklist for tenant migrations.
Timeline (PT)
- 2:00 AM – Maintenance completes successfully.
- 10:00 AM – Customer report received; “answers without facts” alert fires; incident declared.
- 10:20 AM – Issue traced to KB not bound to tenant indices.
- 11:00 AM – Fix deployed; per-tenant KB rebuilt/bound; answering guarded by circuit breaker.
- 3:00 PM – Reprocessing complete; metrics normalized; incident resolved.
Questions? Email support@wolfia.com or see updates on status.wolfia.com.