/**
 * ShardId - Value Object for shard identity
 *
 * A shard identifies a specific mailbox within a realm.
 * For browser tabs, shard is currently always "00" (single shard model).
 *
 * IMPORTANT: Shard is NOT the same as exec-token or tab-suffix.
 * - Exec-token: identifies a runtime instance (tab-123abc)
 * - Shard: identifies a mailbox partition (00, 01, etc.)
 *
 * In browser, we use a single shard model where shard="00".
 * Future multi-shard scenarios would require coordination.
 */
/**
 * Default shard for browser tabs (single shard model).
 */
export declare const DEFAULT_SHARD = "00";
export declare class ShardId {
    private readonly _value;
    private constructor();
    /**
     * Create a ShardId from a string.
     * Throws if the value is invalid.
     */
    static of(value: string): ShardId;
    /**
     * Create the default shard (for browser single-shard model).
     */
    static default(): ShardId;
    /**
     * Create a ShardId, returning default if invalid.
     */
    static tryOf(value: string | undefined | null): ShardId;
    /**
     * Get the raw string value.
     */
    get value(): string;
    /**
     * Check equality with another ShardId.
     */
    equals(other: ShardId | null | undefined): boolean;
    /**
     * Check if this is the default shard.
     */
    isDefault(): boolean;
    toString(): string;
    toJSON(): string;
}
export declare function isShardId(value: unknown): value is ShardId;
//# sourceMappingURL=shard_id.d.ts.map