# A cursor is a checkpoint, not a page number
[Content hub](/en/ai/content)
- type: article
- published_at: 2026-08-13
- tags: cursor, reliability, sync
Understand how the private sync ledger advances without replaying the last page or restarting from the beginning.
## Content
Private sync is an ordered ledger. Its cursor identifies the last record already delivered, so a client can resume after interruption without guessing an offset.
## Advance on every non-empty page
Even the final non-empty response carries the cursor of its last record. The client persists that value only after applying the page successfully.
## Ask once more
A request after the saved cursor returns an empty page. That empty response confirms the current end of the ledger; it does not send the client back to its first record.
## Keep catalog semantics separate
Public catalog pagination has a different reading model and may use `null` at its final page. Treating both cursors as one generic pagination convention would hide their distinct recovery guarantees.