Removes one document. Your Agent stops using it straight away. Our stored copies are kept for 30 days and then erased for good; within those 30 days our team can restore a document removed by mistake — see Getting help. This is the same removal the Knowledge Base Manager page performs, with the same safety checks, so a document the page would refuse is refused here too (see the 409 responses). Removing a document that is already gone returns 404, so a retry is safe.