Add other prefixes

22.md

@@ -20,13 +20,13 @@ A comment is an event of `kind:1111` with plaintext `.content`
 (no HTML, no Markdown nor other formatting).
 
 **It must have a `k` tag** pointing to the kind of the subject being commented on.
-It has a prefix: `"n:"` for nostr subjects and `"r:"` for url ones.
+Its value has a prefix: `"n:"` for nostr subjects and other prefixes (listed in a section ahead)
+for things that aren't nostr events.
 
 For example, when commenting on a `kind:30023`, the `k` tag is set to "n:30023".
 When replying to another `kind:1111`, the `k` tag is set to "n:1111".
-If commenting on an `https://abc.com/articles/1` article the `k` tag is set to "r:https://abc.com" (its domain).
 
-The `k` tag is useful to fetch top-level comments about events of specific kinds (or domains), for example,
+The `k` tag is useful to fetch top-level comments about events of specific types, for example,
 by filtering with `{ "#k": ["n:30023"], "kinds": [1111] }`.
 
 **An uppercase `K` tag must also be present.** The difference is that it is set to the original post (the one starting the thread) kind.
@@ -35,8 +35,8 @@ This way a client can request all comments related to the kind it supports, not
 ### Threads
 
 **There is always an `o` tag** pointing to the original post that started the thread.
-It can be an event id (with an `"i:<event-kind>:<event-pubkey>:"` prefix),
-an event address (`"a:"` prefix) or an url (`"r:"` prefix). The second value
+Its value can be an event id (with an `"i:<event-kind>:<event-pubkey>:"` prefix),
+an event address (`"a:"` prefix) or others shown at below section. The second value
 is the optional recommended relay url where the referenced event may be found.
 This tag is useful to load all messages of a thread at once.
 
@@ -46,12 +46,19 @@ Examples:
 
 - `["o", "i:<event-kind>:<event-pubkey>:<event-id>", "<relay-url, optional>"]`
 - `["o", "a:<event-kind>:<event-pubkey>:<d-tag, optional>", "<relay-url, optional>"]`
-- `["o", "r:https://abc.com/articles/1/"]`
 
 Also, **there is always an `r` tag** pointing to the subject being directly commented on or replied to, using the
 same structure of the `o` tag.
 This tag is useful to lazily load a thread.
 
+### Other possible `o`/`r` tag values and their corresponding `K/k` tag values
+
+| `o`/`r` tag | corresponding `K/k` tag |
+| - | - |
+| "r:`<url>`" | "r:`<domain>`" |
+| "t:`<topic>`" | "#:t" |
+| "g:`<geohash>`" | "#:g" |
+
 #### Thread Relays
 
 If the original post being commented on is a nostr event and
@@ -68,7 +75,7 @@ the client supports the [NIP-65](65.md) relay usage spec,
     // referencing the OP
     ["o", "r:https://abc.com/articles/1/"],
     // replying to a parent kind:1111 comment
-    ["r", "i:1111:f7234bd4c1394dda46d09f35bd384dd30cc552ad5541990f98844fb06676e9ca:5c83da77af1dec6d7289834998ad7aafbd9e2191396d75ec3cc27f5a77226f36"],
+    ["r", "i:1111:f7234bd4c1394dda46d09f35bd384dd30cc552ad5541990f98844fb06676e9ca:5c83da77af1dec6d7289834998ad7aafbd9e2191396d75ec3cc27f5a77226f36", "wss://example.relay"],
     // the OP "kind"; for an url, the kind is its domain
     ["K", "r:https://abc.com"]
     // the parent kind
@@ -84,8 +91,8 @@ the client supports the [NIP-65](65.md) relay usage spec,
   content: 'Great blog post! Check this out nostr:npub1sn0wdenkukak0d9dfczzeacvhkrgz92ak56egt7vdgzn8pv2wfqqhrjdv9.',
   tags: [
     // top-level comments have the same o and r tags
-    ["o", "a:30023:3c9849383bdea883b0bd16fece1ed36d37e37cdde3ce43b17ea4e9192ec11289:f9347ca7"],
-    ["r", "a:30023:3c9849383bdea883b0bd16fece1ed36d37e37cdde3ce43b17ea4e9192ec11289:f9347ca7"],
+    ["o", "a:30023:3c9849383bdea883b0bd16fece1ed36d37e37cdde3ce43b17ea4e9192ec11289:f9347ca7", "wss://example.relay"],
+    ["r", "a:30023:3c9849383bdea883b0bd16fece1ed36d37e37cdde3ce43b17ea4e9192ec11289:f9347ca7", "wss://example.relay"],
     // the OP kind
     ["K", "n:30023"]
     // the parent kind