Nostr Tags

Tags are key components of Nostr events that provide additional context, metadata, and relationships between events. They are especially important for the discoverability and interconnectedness of the Nostr protocol.

Available Tag Definitions

The following tags have detailed definitions in this documentation:

Tag Name	Description	Defined in
client	Identifies the client application that published an event	NIP-89

Tag Format

In Nostr events, tags are represented as arrays of strings within the tags array of an event. The first element of a tag array is always the tag name, followed by one or more values.

Example:

{
  "kinds": 1,
  "tags": [
    ["client", "MyNostrClient"],
    ["e", "5c83da77af1dec6d7289834998ad7aafbd9e2191396d75ec3cc27f5a77226f36", "", "reply"],
    ["p", "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245"]
  ],
  // other fields...
}

Tag Categories

Tags in Nostr can serve several purposes:

1. Referencing other events (e.g., e tag for event references)
2. Referencing users (e.g., p tag for pubkey references)
3. Providing metadata (e.g., client tag for identifying the publishing application)
4. Defining relationships (e.g., d tag for replaceable events)
5. Structuring content (e.g., subject tag for setting a title)

Contributing

To add a new tag definition to this documentation, use the following command:

deno task generate:tag <tag_name> <nip_number>