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+# MSC3994: Display why an event caused a notification
+
+Currently users may not understand why a particular event caused a notification. This can be confusing, lead to notification fatigue, and make creating a custom notification setup difficult.
+
+Currently it is not possible to identify which push rule triggered an action (notification/highlight/ping) for an event without rerunning push processing for that event on the client.
+
+By identifying which rule triggered an action clients can reduce user confusion and enable better management of push rules.
+
+For example: a user receiving pings for a keyword they forgot they had configured can easily understand the pings, and remove the keyword rule.
+
+## Proposal
+
+Extend the `Notification` object returned by [`GET /notifications`](https://spec.matrix.org/latest/client-server-api/#listing-notifications) to include the `kind` and `rule_id` of the executed push rule. 
+`kind` and `rule_id` (along with `room_id` and `profile_tag` already present) will enable the client to uniquely identify the matched rule locally if necessary.
+
+| Name | Type | Description |
+|--|--|--|
+| `rule_kind` | [push rule kind](https://spec.matrix.org/latest/client-server-api/#push-rules) (`override` \| `content` \| `room` \| `sender` \| `underride`) | `kind` of the executed push rule |
+| `rule_id` | string | `rule_id` of the executed push rule |
+
+
+## Alternatives
+
+Let clients determine the executed push rule. This would mean rerunning push processing client-side on notifications fetched from `/notifications`.
+Clients likely already do client-side push processing in many cases. For example, Element Web runs client-side push rule processing for encrypted events, and on `/sync` response.
+
+## Security considerations
+
+N/A
+
+## Unstable prefix
+While this MSC is not included in the spec `rule_kind` and `rule_id` should use the unstable prefixes `org.matrix.msc3994.rule_kind` and `org.matrix.msc3994.rule_id` respectively