nips/09.md

NIP-09

Event Retraction

draft optional

A special event with kind 5, meaning "retraction" is defined as having a list of one or more e or a tags, each referencing an event the author is requesting to be retracted. Retraction requests SHOULD include a k tag for the kind of each event being retracted.

The event's content field MAY contain a text note describing the reason for the retraction.

For example:

{
  "kind": 5,
  "pubkey": <32-bytes hex-encoded public key of the event creator>,
  "tags": [
    ["e", "dcd59..464a2"],
    ["e", "968c5..ad7a4"],
    ["a", "<kind>:<pubkey>:<d-identifier>"],
    ["k", "1"],
    ["k", "30023"]
  ],
  "content": "these posts were published by accident",
  ...other fields
}

Relays SHOULD delete or stop publishing any referenced events that have an identical pubkey as the retraction request. Clients SHOULD hide or otherwise indicate a retraction status for referenced events.

Relays SHOULD continue to publish/share the retraction events indefinitely, as clients may already have the event that's intended to be retracted. Additionally, clients SHOULD broadcast retraction events to other relays which don't have it.

When an a tag is used, relays SHOULD delete all versions of the replaceable event up to the created_at timestamp of the retraction event.

Client Usage

Clients MAY choose to fully hide any events that are referenced by valid retraction events. This includes text notes, direct messages, or other yet-to-be defined event kinds. Alternatively, they MAY show the event along with an icon or other indication that the author has "disowned" the event. The content field MAY also be used to replace the retracted events' own content, although a user interface should clearly indicate that this is a retraction reason, not the original content.

A client MUST validate that each event pubkey referenced in the e tag of the retraction request is identical to the retraction request pubkey, before hiding or deleting any event. Relays can not, in general, perform this validation and should not be treated as authoritative.

Clients display the retraction event itself in any way they choose, e.g., not at all, or with a prominent notice.

Clients MAY choose to inform the user that their request for retraction does not guarantee deletion because it is impossible to delete events from all relays and clients.

Relay Usage

Relays MAY validate that a retraction event only references events that have the same pubkey as the retraction itself, however this is not required since relays may not have knowledge of all referenced events.

Retracting a Retraction

Publishing a retraction event against a retraction has no effect. Clients and relays are not obliged to support "unretract" functionality.