Clear every label-level operator-tunable override in one call, restoring the label's resolved tunables to the static defaults (per-Agent overrides on individual LinkAgent records still layer on top). The resolved operator_tunables view is recomputed on the response. To clear a single override instead, PATCH that field to null via PATCH /link/{workspace_id}/label/{label}. Idempotent — clearing when no label-level overrides are set is a no-op success.