NIPs nostr improvement proposals

NIP-10 - On "e" and "p" tags in Text Events (kind 1).

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On "e" and "p" tags in Text Events (kind 1).

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This NIP describes how to use "e" and "p" tags in text events, especially those that are replies to other text events. It helps clients thread the replies into a tree rooted at the original event.

Positional "e" tags (DEPRECATED)

This scheme is in common use; but should be considered deprecated.

["e", <event-id>, <relay-url>] as per NIP-01.


The positions of the "e" tags within the event denote specific meanings as follows:

This scheme is deprecated because it creates ambiguities that are difficult, or impossible to resolve when an event references another but is not a reply.

Marked "e" tags (PREFERRED)

["e", <event-id>, <relay-url>, <marker>, <pubkey>]


Those marked with "reply" denote the id of the reply event being responded to. Those marked with "root" denote the root id of the reply thread being responded to. For top level replies (those replying directly to the root event), only the "root" marker should be used. Those marked with "mention" denote a quoted or reposted event id.

A direct reply to the root of a thread should have a single marked "e" tag of type "root".

This scheme is preferred because it allows events to mention others without confusing them with <reply-id> or <root-id>.

<pubkey> SHOULD be the pubkey of the author of the e tagged event, this is used in the outbox model to search for that event from the authors write relays where relay hints did not resolve the event.

The "p" tag

Used in a text event contains a list of pubkeys used to record who is involved in a reply thread.

When replying to a text event E the reply event's "p" tags should contain all of E's "p" tags as well as the "pubkey" of the event being replied to.

Example: Given a text event authored by a1 with "p" tags [p1, p2, p3] then the "p" tags of the reply should be [a1, p1, p2, p3] in no particular order.