Kind 10003: Bookmarks

Overview

Bookmarks events (kind 10003) allow users to save and organize content they want to reference later. This standard replaceable event kind serves as a global, uncategorized list of items a user wants to preserve, similar to bookmarks in a web browser. Bookmarks can contain references to notes, articles, hashtags, and external URLs.

Specification

Property	Value
Kind Number	10003
Event Range	Replaceable
Defined in	NIP-51

Content Format

The content field can contain encrypted private bookmarks using NIP-04 encryption. The encrypted content follows the same structure as the public tags but is only visible to the creator. This allows users to have both public bookmarks (in tags) and private bookmarks (encrypted in content).

Schema

For encrypted private bookmarks:

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

The encrypted content, when decrypted, would reveal a JSON array of tags:

[
  ["e", "<event-id>", "<relay-url>"],
  ["a", "<addressable-event-coordinate>", "<relay-url>"],
  ["t", "<hashtag>"],
  ["r", "<url>"]
]

Tags

Tag Name	Description	Format	Required
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

Client Behavior

Clients should:

1. Provide a user interface for viewing and managing bookmarks
2. Support adding items to bookmarks from various contexts (notes, articles, hashtags, URLs)
3. Handle both public (in tags) and private (encrypted in content) bookmarks
4. When displaying bookmarks:
   • 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 bookmark collections
5. Include options for adding and removing bookmarks
6. When processing encrypted bookmarks, decrypt using NIP-04 and the user's keys
7. Maintain the chronological order of bookmarks, with newest additions at the end

Relay Behavior

Relays should:

1. Handle kind 10003 events as normal replaceable events
2. Store these events to allow clients to retrieve the user's bookmarks
3. Not attempt to interpret or enforce bookmark behavior (this is client-side functionality)

Use Cases

• Saving interesting notes for later reference
• Bookmarking long-form articles to read later
• Creating collections of external web resources
• Tracking favorite hashtags for regular browsing
• Building a personal library of valuable content
• Saving references for research or projects
• Creating reading lists of content to revisit

Example

{
  "id": "b5a2771fb9db3ca36c6c6502aed3e2ef49d4d64b3ed3f3e5ef973c8f9eaae5ed",
  "pubkey": "854043ae8f1f97430ca8c1f1a090bdde6488bd5115c7a45307a2a212750ae4cb",
  "created_at": 1699597889,
  "kind": 10003,
  "tags": [
    ["e", "04d2c21d3ecc928f1d75e78d6dd1896356dc1120d2b9e09be9494e41607389cf", "wss://relay.nostr.example.com"],
    ["a", "30023:854043ae8f1f97430ca8c1f1a090bdde6488bd5115c7a45307a2a212750ae4cb:article-about-nostr", "wss://relay.nostr.example.com"],
    ["t", "nostr"],
    ["r", "https://github.com/nostr-protocol/nips"]
  ],
  "content": "TJob1dQrf2ndsmdbeGU+05HT5GMnBSx3fx8QdDY/g3NvCa7klfzgaQCmRZuo1d3WQjHDOjzSY1+MgTK5WjewFFumCcOZniWtOMSga9tJk1ky00tLoUUz==?iv=S3rFeFr1gsYqmQA7bNnNTQ==",
  "sig": "a9a4e2192eede77e6c9d24ddfab95ba3ff7c03fbd07ad011fff245abea431fb4d3787c2d04aad001cb039cb8de91d83ce30e9a94f82ac3c5a2372aa1294a96bd"
}

References

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

Related Kinds

• Kind 1: Short Text Note - Notes that can be bookmarked
• Kind 30023: Long-form Content - Articles that can be bookmarked
• Kind 10001: Pinned Notes - Notes highlighted on a profile
• Kind 30003: Bookmark Sets - Categorized bookmark collections

Notes

• Bookmarks are one of several standard list types defined in NIP-51
• Users can only have one global bookmark list (since it's a replaceable event)
• For categorized bookmarks, users should use Kind 30003 (Bookmark Sets)
• When new items are added to bookmarks, clients should append them to the end
• The bookmarks kind replaces the deprecated parameterized replaceable event with kind 30001 and d tag "bookmark"
• 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