/** The one decoder for a cron's stored sink JSON.
 *
 *  A sink is armed as a CLI spec string (`node:<id>` | `spawn:<kind>` |
 *  `human`), validated and encoded to JSON once at arm time
 *  (`api/handlers/crons.ts`), and thereafter read back in exactly two places:
 *  the runner, which dispatches a delivery on it, and the DTO mapper, which
 *  renders it. Both go through here so the stored shape has a single reader.
 *
 *  A malformed stored value decodes as no-sink rather than throwing: a cron
 *  that cannot deliver must still run, and must still list.
 */
export type ParsedSink = {
    kind: 'node';
    node: string;
} | {
    kind: 'spawn';
    spawn: string;
} | {
    kind: 'human';
} | null;
/** Stored JSON → typed shape. `{}`, malformed JSON, and an unrecognised shape
 *  all read as null (no sink). */
export declare function parseSink(sinkJson: string): ParsedSink;
/** Stored JSON → the display spec the CLI armed with, or null when the cron
 *  never delivers. The exact inverse of the arm-time encoding. */
export declare function sinkDisplay(sinkJson: string): string | null;