Kind 9002: Group Metadata Edit

Overview

This event is used to modify the metadata of a relay-based group. It allows group administrators to update information such as the group's name, picture, description, and visibility settings.

Specification

Property	Value
Kind Number	9002
Event Range	Regular
Defined in	NIP-29

Content Format

The content field can contain an optional reason for the metadata edit.

Schema

"optional reason"

Tags

Tag Name	Description	Format	Required
h	Group identifier	["h", "<group-id>"]	Yes
name	Group name	["name", "<group-name>"]	No
picture	Group picture URL	["picture", "<picture-url>"]	No
about	Group description	["about", "<description>"]	No
public or private	Group visibility	["public"] or ["private"]	No
open or closed	Group join policy	["open"] or ["closed"]	No
previous	Timeline references	["previous", "<event-id-prefix>"]	No, but recommended

Client Behavior

Clients with appropriate permissions can send this event to modify a group's metadata. The client should include the group ID in the h tag and any metadata fields to be modified as additional tags.

Clients should include timeline references in the previous tag to prevent messages from being used out of context.

Relay Behavior

Relays should validate that:

1. The sender has the appropriate permissions to edit the group's metadata.
2. The event contains a valid h tag with the group ID.
3. The timeline references in the previous tag, if present, refer to events in the relay's database.

If validation succeeds, the relay should process the event, update the group's metadata accordingly, and generate or update the kind 39000 event for the group to reflect these changes.

Use Cases

• Updating a group's name or picture.
• Changing a group's visibility from public to private or vice versa.
• Updating a group's join policy from open to closed or vice versa.
• Modifying a group's description.

Example

{
  "id": "...",
  "pubkey": "1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef",
  "created_at": 1671217411,
  "kind": 9002,
  "tags": [
    ["h", "vegans-united"],
    ["name", "Vegans United"],
    ["about", "A place where vegans fight with each other"],
    ["picture", "https://vegans-united.com/new-logo.png"],
    ["public"],
    ["open"],
    ["previous", "a1b2c3d4"]
  ],
  "content": "Updating our group description and name to be more professional",
  "sig": "..."
}

References

• NIP-29: Relay-based Groups

Related Kinds

• Kind 39000: Group Metadata

Notes

The event should only be accepted by relays if it comes from a user with appropriate permissions (e.g., a group admin with the capability to edit metadata).

After processing this event, the relay is expected to generate or update the corresponding kind 39000 event to reflect the metadata changes.