Variable: IDENTIFIER_KEY_DISCARD_REASONS

const IDENTIFIER_KEY_DISCARD_REASONS: readonly ["spent", "unpublished"]

Defined in: packages/contracts/src/schemas/audit-issuance.ts:417

Why issuance had the agent destroy keys (plan 3a, rulings 1 and 2):

• spent: an update key whose entry is durable. It signed entry n, entry n is published, and the method accepts nothing more from it, so keeping it would be keeping a key that can only be misused;
• unpublished: keys generated for a document that was never published: a preview rendered again before it was published, a failed publication gate, or the next update key a failed update carried over to the following cycle.

An assertion key that an update replaced is not a reason and never will be: it stays on the token, because a credential signed under it must stay verifiable, and the identifier's view lists it as retired. The plan's table names retired only to say so, which is why it is not a member here. The list only widens.