Kind 30003: Bookmark Sets

Overview

Bookmark Sets events (kind 30003) allow users to organize saved content into categorized collections. This parameterized replaceable event kind enables users to create multiple themed bookmark folders, similar to browser bookmark folders. Unlike the global Bookmarks list (kind 10003), Bookmark Sets provide a way to group related content into labeled separate collections for better organization and retrieval.

Specification

Property	Value
Kind Number	30003
Event Range	Parameterized Replaceable
Defined in	NIP-51

Content Format

The content field can contain encrypted private bookmark entries using NIP-04 encryption. The encrypted content follows the same structure as the public tags but is only visible to the creator. It can also contain a description or notes about the bookmark set.

Schema

For encrypted private bookmarks:

"content": "<NIP-04 encrypted JSON array of tags>"

For descriptive content:

"content": "My collection of resources for learning Nostr protocol development."

Tags

Tag Name	Description	Format	Required
d	Set identifier	["d", "<set-name>"]	Yes
e	Referenced note (kind 1)	["e", "<event-id>", "<relay-url>"]	No
a	Referenced article (kind 30023)	["a", "30023:<pubkey>:<identifier>", "<relay-url>"]	No
t	Hashtag	["t", "<hashtag>"]	No
r	External URL	["r", "https://example.com/page"]	No
title	Human-readable title	["title", "<title-text>"]	No
description	Description of the set	["description", "<description-text>"]	No
image	Image URL for the set	["image", "<image-url>"]	No

Client Behavior

Clients should:

1. Allow users to create, view, and manage multiple bookmark sets
2. Use the d tag parameter to distinguish between different bookmark sets
3. Display the set's title, description, and image when available
4. Provide a UI for organizing bookmarks into different sets
5. Support adding items to bookmark sets from various contexts
6. When displaying bookmark sets:
   • Fetch full content for e-tagged and a-tagged events
   • Render appropriate UI for different bookmark types
   • Support opening external URLs
   • Provide search or filter functionality for large sets
7. Include options for adding and removing bookmarks from sets
8. When processing encrypted bookmarks, decrypt using NIP-04 and the user's keys
9. Maintain the chronological order of bookmarks, with newest additions at the end

Relay Behavior

Relays should:

1. Handle kind 30003 events as parameterized replaceable events with the d tag as discriminator
2. Store these events to allow clients to retrieve the user's bookmark sets
3. Not attempt to interpret or enforce bookmark behavior (this is client-side functionality)

Use Cases

• Creating topic-based bookmark collections (e.g., "Bitcoin Resources", "Art References")
• Organizing reading lists by subject
• Building curated collections of interesting content
• Sharing topical resource collections
• Creating research materials for projects
• Making personal learning libraries
• Organizing content by interests or hobbies

Example

{
  "id": "8d3f8b08742b92d19f91377a8c3b4e5f0a08dfcb6c38a143494a8c055ab3e019",
  "pubkey": "854043ae8f1f97430ca8c1f1a090bdde6488bd5115c7a45307a2a212750ae4cb",
  "created_at": 1699597889,
  "kind": 30003,
  "tags": [
    ["d", "nostr-development"],
    ["title", "Nostr Development Resources"],
    ["description", "Helpful resources for Nostr protocol development"],
    ["image", "https://example.com/nostr-icon.png"],
    ["e", "04d2c21d3ecc928f1d75e78d6dd1896356dc1120d2b9e09be9494e41607389cf", "wss://relay.nostr.example.com"],
    ["a", "30023:854043ae8f1f97430ca8c1f1a090bdde6488bd5115c7a45307a2a212750ae4cb:nostr-api-guide", "wss://relay.nostr.example.com"],
    ["r", "https://github.com/nostr-protocol/nips"],
    ["t", "nostr-dev"],
    ["r", "https://nostr.how/developers/get-started"]
  ],
  "content": "My go-to resources for Nostr protocol development and implementation references.",
  "sig": "a9a4e2192eede77e6c9d24ddfab95ba3ff7c03fbd07ad011fff245abea431fb4d3787c2d04aad001cb039cb8de91d83ce30e9a94f82ac3c5a2372aa1294a96bd"
}

References

• NIP-51: Lists
• NIP-04: Encrypted Direct Messages

Related Kinds

• Kind 10003: Bookmarks - Global, uncategorized bookmark list
• Kind 1: Short Text Note - Notes that can be bookmarked
• Kind 30023: Long-form Content - Articles that can be bookmarked

Notes

• Bookmark Sets are parameterized lists, allowing users to have multiple sets with different d tag values
• The d tag is required for parameterized replaceable events to work correctly
• Multiple bookmark sets can co-exist, each with a different d value
• Title, description, and image tags help with UI presentation and set identification
• When new items are added to bookmark sets, clients should append them to the end
• Bookmark Sets allow for more granular organization than the global Bookmark list
• Bookmark privacy can be managed by choosing whether to use public tags or encrypted content
• For maximum privacy, sensitive bookmarks should be stored in the encrypted content field