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+NIP-05
+======
+
+Mapping Nostr keys to DNS-based internet identifiers
+----------------------------------------------------
+
+`draft` `optional` `author:fiatjaf`
+
+On events of type `0` (`set_metadata`) one can specify the key `"nip05"` with an [internet identifier](https://datatracker.ietf.org/doc/html/rfc5322#section-3.4.1) (an email-like address) as the value. Although there is a link to a very liberal "internet identifier" specification above, NIP-05 assumes the `<local-part>` part will be restricted to the characters `a-z0-9-_.`, case insensitive.
+
+Upon seeing that, the client splits the identifier into `<local-part>` and `<domain>` and use these values to make a GET request to `https://<domain>/.well-known/nostr.json?name=<local-part>`.
+
+The result should be a JSON document object with a key `"names"` that should then be a mapping of names to public keys. If the public key for the given `<name>` matches the `pubkey` from the `set_metadata` event, the client then concludes that the given pubkey can indeed be referenced by its identifier.
+
+### Example
+
+If a client sees an event like this:
+
+```json
+{
+  "pubkey": "b0635d6a9851d3aed0cd6c495b282167acf761729078d975fc341b22650b07b9",
+  "kind": 0,
+  "content": "{\"name\": \"bob\", \"nip05\": \"bob@example.com\"}"
+  ...
+}
+```
+
+It will make a GET request to `https://example.com/.well-known/nostr.json?name=bob` and get back a response that will look like
+
+```json
+{
+  "names": {
+    "bob": "b0635d6a9851d3aed0cd6c495b282167acf761729078d975fc341b22650b07b9"
+  }
+}
+```
+
+That will mean everything is alright.
+
+## Notes
+
+### User Discovery implementation suggestion
+
+A client can also use this to allow users to search other profiles. If a client has a search box or something like that, a user may be able to type "bob@example.com" there and the client would recognize that and do the proper queries to obtain a pubkey and suggest that to the user.
+
+### Showing just the domain as an identifier
+
+Clients may treat the identifier `_@domain` as the "root" identifier, and choose to display it as just the `<domain>`. For example, if Bob owns `bob.com`, he may not want an identifier like `bob@bob.com` as that is redundant. Instead Bob can use the identifier `_@bob.com` and expect Nostr clients to show and treat that as just `bob.com` for all purposes.
+
+### Reasoning for the `/.well-known/nostr.json?name=<local-part>` format
+
+By adding the `<local-part>` as a query string instead of as part of the path the protocol can support both dynamic servers that can generate JSON on-demand and static servers with a JSON file in it that may contain multiple names.