Querying events by tags presence

100.md

@@ -0,0 +1,40 @@
+NIP-100
+=======
+
+Querying Events by Tags Presence
+---------------------------------
+
+`draft` `optional` `author:fernandolguevara` `requires:nip-12`
+
+This NIP allows clients to query events from relays based on the presence or absence of specific tags.
+
+### Presense:
+The filter condition matches if there is at least one tag name in common with the filter and event.
+
+### Absence:
+The filter condition matches if there is at least one tag in the filter that are not present in the event.
+
+Example Subscription Filter
+---------------------------
+
+Below are some example filters that demonstrate tag presence and absence:
+
+1. Filter to match events with a `g` tag:
+
+```json
+{
+  "tags": ["g"]
+}
+```
+
+2. Filter to match events without the presence of the `e` tag:
+
+```json
+{
+  "tags": ["!e"]
+}
+```
+
+Suggested Use Cases
+-------------------
+One of the suggested use cases for this NIP is for location-specific events. Clients can utilize the provided filter example to locate events with specific location-related tags, regardless of how the location information has been stored in the events.

README.md

@@ -68,6 +68,7 @@ They exist to document what may be implemented by [Nostr](https://github.com/nos
 - [NIP-94: File Metadata](94.md)
 - [NIP-98: HTTP Auth](98.md)
 - [NIP-99: Classified Listings](99.md)
+- [NIP-100: Querying Events by Tags Presence](100.md)
 
 ## Event Kinds