Case 01 · Silent failure audit
A pipeline that looked green while it had truncated its output for months.
An AI notes pipeline was feeding ~22,500 tokens of transcript into a model capped at 8,192 — a 2.7× overflow. The model silently saw a fraction of each input and produced confident, well-formatted, incomplete notes. No error was ever raised. We traced it through provenance metadata, reproduced the root cause, and rebuilt every affected output with a full rollback path.
- Root cause: model pinned to 8K context but capable of 32K — exposed via model introspection, not guesswork
- A schema collision caught in pre-flight simulation before it could corrupt 28 records
- Backup-first, HITL sign-off on every irreversible step, idempotent restartable rebuild
Before: “the transcript is quite extensive and gets cut off, but here's a summary…” — the model narrating that it only saw a fragment. After: a complete, structured summary of the entire session.