document_version_id is an internal UUID, not a human-meaningful version like the demo corpus's markdown frontmatter -- confirmed live it made the fallback answer read as "Per \"vehicle-checkout-procedure.md\" (v2e139422-b10b-...)". Still shown on the source card itself, just not in the composed sentence. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>