Expand NIP 03 to include relay and user notaries

03.md

@@ -1,12 +1,19 @@
 NIP-03
 ======
 
-OpenTimestamps Attestations for Events
---------------------------------------
+Timestamp Attestations for Events
+---------------------------------
 
 `draft` `optional`
 
-This NIP defines an event with `kind:1040` that can contain an [OpenTimestamps](https://opentimestamps.org/) proof for any other event:
+This NIP defines strategies for establishing when an event was first found on the nostr network:
+
+- [OpenTimestamps](#opentimestamps)
+- [Attestation Event](#attestation-event)
+
+# OpenTimestamps
+
+An event with `kind:1040` contains an [OpenTimestamps](https://opentimestamps.org/) proof for any event:
 
 ```json
 {
@@ -22,7 +29,7 @@ This NIP defines an event with `kind:1040` that can contain an [OpenTimestamps](
 - The OpenTimestamps proof MUST prove the referenced `e` event id as its digest.
 - The `content` MUST be the full content of an `.ots` file containing at least one Bitcoin attestation. This file SHOULD contain a **single** Bitcoin attestation (as not more than one valid attestation is necessary and less bytes is better than more) and no reference to "pending" attestations since they are useless in this context.
 
-### Example OpenTimestamps proof verification flow
+## Example OpenTimestamps proof verification flow
 
 Using [`nak`](https://github.com/fiatjaf/nak), [`jq`](https://jqlang.github.io/jq/) and [`ots`](https://github.com/fiatjaf/ots):
 
@@ -32,3 +39,28 @@ Using [`nak`](https://github.com/fiatjaf/nak), [`jq`](https://jqlang.github.io/j
 - sequence ending on block 810391 is valid
 timestamp validated at block [810391]
 ```
+
+# Attestation Event
+
+Users MAY verify when they first saw an event by publishing a `kind:4341` event.
+
+- One or more `e` tags MUST be included indicating event ids and timestamps. Event addresses MUST NOT be used.
+- One or more `k` tags SHOULD be included indicating the kind(s) of the event(s) being referred to.
+- The `content` field MAY provide any human-readable explanation of the event.
+
+```jsonc
+{
+  "kind": 4341,
+  "content": "I vaguely remember hearing about this note last year",
+  "created_at": 1738617405,
+  "tags": [
+    ["alt", "A timestamp attestation event"],
+    ["e", "<event-id>", "<relay-url>", "<author-pubkey>"],
+    ["k", "10002"]
+  ]
+}
+```
+
+Note that user-provided attestations provide a weaker guarantee than OTS proofs. Depending on the importance of the verification, multiple users with a good reputation should be consulted in order to determine a reasonable result.
+
+Relays MAY also provide these attestations by generating and signing them on the fly using the `self` pubkey listed in the relay's [NIP 11](./11.md) document.

README.md

@@ -150,6 +150,7 @@ They exist to document what may be implemented by [Nostr](https://github.com/nos
 | `2003`        | Torrent                         | [35](35.md)                            |
 | `2004`        | Torrent Comment                 | [35](35.md)                            |
 | `2022`        | Coinjoin Pool                   | [joinstr][joinstr]                     |
+| `4341`        | Timestamp Attestation           | [03](03.md)                            |
 | `4550`        | Community Post Approval         | [72](72.md)                            |
 | `5000`-`5999` | Job Request                     | [90](90.md)                            |
 | `6000`-`6999` | Job Result                      | [90](90.md)                            |