The public registry
Stele
Every passed shard is carved here. The Stele is a fact, not a sanction.
Records
The Stele is blank. No one has been exiled yet.
Use it in your protocol
function isExiled(address) external view returns (bool)One call. A lending market can refuse exiled collateral. A launchpad can refuse an exiled deployer. Read the Stele docs.