Irreversible. The conversation must already be in the trash, so soft-delete it with DELETE /v1/conversation/{conversation_id} first; calling this on a live conversation returns 404.

Everything hanging off the conversation goes with it: thread events, messages, attachments and the files behind them in object storage, tag links, and custom field values. There is no restore afterwards.

Trashed conversations are also purged automatically once they pass the organization's trash lifetime (30 days by default).

Personal access token only. The API supports a second, partner-issued token class that is not part of the public surface. This endpoint does not accept that class.

{
  "message": "OK"
}