/**
 * A validated tenant identifier.
 *
 * Nominal by construction: structurally a `string`, but the phantom brand makes
 * it unassignable from an arbitrary string. Assignment the other way
 * (`TenantId` → `string`) stays legal on purpose, so composition code can pass
 * it as a SQL parameter or key prefix without a cast.
 */
export type TenantId = string & {
    readonly __byokTenantId: unique symbol;
};
/**
 * Upper bound on tenant id length. Not a security boundary — a bound so a
 * pathological id cannot become an unbounded key prefix inside a store.
 */
export declare const TENANT_ID_MAX_LENGTH = 200;
/**
 * Separator for flat composite keys. `NUL` cannot appear in a tenant id that a
 * control plane can express in a URL, a header, or a SQL identifier, and
 * {@link tenantId} rejects it outright — so a composite key is never ambiguous
 * between `(a, bc)` and `(ab, c)`.
 */
export declare const TENANT_KEY_SEPARATOR = "\0";
/**
 * The single mint point for {@link TenantId}.
 *
 * Fail-closed: empty, whitespace-padded, over-long, non-string, or
 * `NUL`-bearing values are rejected rather than normalized. Normalizing here
 * would create a second source of truth for "which tenant is this", because the
 * control plane that issued the id would then disagree with the SDK about its
 * canonical form.
 *
 * @throws {ByokCoreError} code `tenant_id_invalid`.
 */
export declare function tenantId(value: string): TenantId;
/**
 * Non-throwing form of {@link tenantId}, for surfaces that must answer "is this
 * a tenant id?" without building an error (route matching, log redaction).
 * Accepts exactly what {@link tenantId} accepts, never more.
 */
export declare function isTenantId(value: unknown): value is TenantId;
/**
 * Composite key helper for compositions that need a flat key space (in-memory
 * maps, KV namespaces). SQL compositions use a tenant-prefixed composite
 * primary key instead — §12.6.2 layer 3 forbids a bare device/task index
 * regardless of which representation a composition picks.
 */
export declare function tenantKey(tenant: TenantId, ...parts: readonly string[]): string;