1 files changed, 35 insertions, 11 deletions

diff --git a/25.md b/25.md
index f74bcc0..17c203e 100644
--- a/25.md
+++ b/25.md
@@ -5,9 +5,9 @@ NIP-25
 Reactions
 ---------
 
-`draft` `optional` `author:jb55`
+`draft` `optional`
 
-A reaction is a `kind 7` note that is used to react to other notes.
+A reaction is a `kind 7` event that is used to react to other events.
 
 The generic reaction, represented by the `content` set to a `+` string, SHOULD
 be interpreted as a "like" or "upvote".
@@ -18,32 +18,56 @@ downvote or dislike on a post. A client MAY also choose to tally likes against
 dislikes in a reddit-like system of upvotes and downvotes, or display them as
 separate tallies.
 
-The `content` MAY be an emoji, in this case it MAY be interpreted as a "like" or "dislike",
-or the client MAY display this emoji reaction on the post.
+The `content` MAY be an emoji, or [NIP-30](30.md) custom emoji in this case it MAY be interpreted as a "like" or "dislike",
+or the client MAY display this emoji reaction on the post. If the `content` is an empty string then the client should
+consider it a "+".
 
 Tags
 ----
 
-The reaction event SHOULD include `e` and `p` tags from the note the user is
-reacting to. This allows users to be notified of reactions to posts they were
-mentioned in. Including the `e` tags enables clients to pull all the reactions
-associated with individual posts or all the posts in a thread.
+The reaction event SHOULD include `e` and `p` tags from the note the user is reacting to (and optionally `a` tags if the target is a replaceable event). This allows users to be notified of reactions to posts they were mentioned in. Including the `e` tags enables clients to pull all the reactions associated with individual posts or all the posts in a thread. `a` tags enables clients to seek reactions for all versions of a replaceable event.
 
-The last `e` tag MUST be the `id` of the note that is being reacted to. 
+The last `e` tag MUST be the `id` of the note that is being reacted to.
 
 The last `p` tag MUST be the `pubkey` of the event being reacted to.
 
+The `a` tag MUST contain the coordinates (`kind:pubkey:d-tag`) of the replaceable being reacted to.
+
+The reaction event MAY include a `k` tag with the stringified kind number of the reacted event as its value.
+
 Example code
 
 ```swift
 func make_like_event(pubkey: String, privkey: String, liked: NostrEvent) -> NostrEvent {
-    var tags: [[String]] = liked.tags.filter { 
-        tag in tag.count >= 2 && (tag[0] == "e" || tag[0] == "p") 
+    var tags: [[String]] = liked.tags.filter {
+        tag in tag.count >= 2 && (tag[0] == "e" || tag[0] == "p")
     }
     tags.append(["e", liked.id])
     tags.append(["p", liked.pubkey])
+    tags.append(["k", liked.kind])
     let ev = NostrEvent(content: "+", pubkey: pubkey, kind: 7, tags: tags)
     ev.calculate_id()
     ev.sign(privkey: privkey)
     return ev
 }
+```
+
+Custom Emoji Reaction
+---------------------
+
+The client may specify a custom emoji ([NIP-30](30.md)) `:shortcode:` in the
+reaction content. The client should refer to the emoji tag and render the
+content as an emoji if shortcode is specified.
+
+```json
+{
+  "kind": 7,
+  "content": ":soapbox:",
+  "tags": [
+    ["emoji", "soapbox", "https://gleasonator.com/emoji/Gleasonator/soapbox.png"]
+  ],
+  ...other fields
+}
+```
+
+The content can be set only one `:shortcode:`. And emoji tag should be one.