Model Card Currency

Explanation

Model Card Currency checks that the model card — the governing document describing the model's purpose, data, performance, limitations, and approved use — is kept up to date whenever the model changes. This matters because stale documentation undermines governance, oversight, and audit: reviewers, risk officers, and regulators rely on the model card to understand what is actually running in production, and an out-of-date card hides material changes such as a new training set, altered thresholds, or new limitations. The metric and calculation method are both Model Card Currency, evidenced by how quickly the card is refreshed after a version change. To implement it, tie model-card updates to the model release/versioning workflow so a deployment cannot be considered complete until the card reflects the new version, timestamp each card revision, and log the version-change time and the card-update time so the gap can be measured and audited. The threshold is that the model card is updated within 72 hours of a version change. As an Immediate-priority control, failing to update within 72 hours constitutes a breach and should trigger escalation to the model owner and governance function, and may warrant flagging the version as non-compliant until its documentation is brought current.