/**
 * Shared identity/isolation scope for the TanStack AI subsystems that persist
 * or recall per-conversation data — `@tanstack/ai-persistence` (keyed CRUD over
 * threads, runs, interrupts) and `@tanstack/ai-memory` (ranked recall/save).
 *
 * Both subsystems answer the same underlying question — "whose data is this?" —
 * so they share ONE identity vocabulary defined here rather than each inventing
 * its own. `threadId` is the single conversation key across the codebase (it is
 * `ChatMiddlewareContext.threadId`, and `conversationId` is deprecated in favor
 * of it); a subsystem must never introduce a second name (`sessionId`,
 * `conversationId`, …) for the same concept.
 *
 * ## Security
 *
 * A `Scope` is an isolation boundary. Derive every field server-side from
 * trusted, validated session state — **never** from client input. `threadId`
 * in particular resolves from a client-supplied value on the request, so a
 * subsystem that reads/writes user-owned data (memory, per-user metadata) must
 * pair it with a server-trusted `userId`/`tenantId` and must not treat a bare
 * client `threadId` as sufficient isolation: thread ids are guessable, so on
 * their own they let one caller read another's data.
 */
export interface Scope {
  /**
   * The conversation this data belongs to. Required — the minimal isolation
   * key both subsystems already center on. Same concept as
   * `ChatMiddlewareContext.threadId`.
   */
  threadId: string
  /**
   * Durable end-user identity, for cross-thread recall and per-user isolation.
   * Optional, but required in practice for any multi-user deployment — a
   * `threadId` alone is not an authorization boundary (see Security above).
   */
  userId?: string
  /**
   * Tenant/organization boundary for multi-tenant deployments. When present,
   * every read and write must be confined to it.
   */
  tenantId?: string
  /**
   * Logical partition within a tenant/user (e.g. separating distinct memory
   * banks or persistence namespaces). Reserved — no subsystem keys on it yet;
   * adapters that don't understand it must ignore it rather than error.
   */
  namespace?: string
}