> For the complete documentation index, see [llms.txt](https://docs.cekat.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.cekat.ai/api-documentation/versioning.md).

# Versioning

Some endpoints accept a `version` query parameter (`YYYY-MM-DD`). With `version=2026-05-22` or later, `created_at` is returned as an ISO 8601 UTC timestamp. Without it, older formats in Asia/Jakarta local time are kept for backward compatibility. New integrations should always send `version=2026-05-22`.