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+NIP-43
+======
+
+Relay Access Metadata and Requests
+----------------------------------
+
+`draft` `optional` `relay`
+
+This NIP defines a way for relays to advertise membership lists, and for clients to request admission to relays on behalf of users.
+
+## Membership Lists
+
+Relays MAY publish a `kind 13534` event which indicates pubkeys that have access to a given relay. This event MUST be signed by the pubkey specified in the `self` field of the relay's [NIP 11](./11.md) document.
+
+The following tags are required:
+
+- A [NIP 70](./70.md) `-` tag
+- A `member` tag containing a hex pubkey should be included for each member
+
+This list should not be considered exhaustive or authoritative. To determine membership, both a `kind 13534` event by the relay, and a `kind 10010` event by the member should be consulted.
+
+Example:
+
+```jsonc
+{
+  "kind": 13534,
+  "pubkey": "<nip11.self>",
+  "tags": [
+    ["-"],
+    ["member", "c308e1f882c1f1dff2a43d4294239ddeec04e575f2d1aad1fa21ea7684e61fb5"],
+    ["member", "ee1d336e13779e4d4c527b988429d96de16088f958cbf6c074676ac9cfd9c958"]
+  ],
+  // ...other fields
+}
+```
+
+## Add User
+
+Relays MAY publish a `kind 8000` event when a member is added to the relay. This event MUST be signed by the pubkey specified in the `self` field of the relay's [NIP 11](./11.md) document.
+
+The following tags are required:
+
+- A [NIP 70](./70.md) `-` tag
+- A `p` tag indicating the member's hex pubkey
+
+Example:
+
+```jsonc
+{
+  "kind": 8000,
+  "pubkey": "<nip11.self>",
+  "tags": [
+    ["-"],
+    ["p", "c308e1f882c1f1dff2a43d4294239ddeec04e575f2d1aad1fa21ea7684e61fb5"]
+  ],
+  // ...other fields
+}
+```
+
+## Remove User
+
+Relays MAY publish a `kind 8001` event when a member is removed from the relay. This event MUST be signed by the pubkey specified in the `self` field of the relay's [NIP 11](./11.md) document.
+
+The following tags are required:
+
+- A [NIP 70](./70.md) `-` tag
+- A `p` tag indicating the member's hex pubkey
+
+Example:
+
+```jsonc
+{
+  "kind": 8001,
+  "pubkey": "<nip11.self>",
+  "tags": [
+    ["-"],
+    ["p", "c308e1f882c1f1dff2a43d4294239ddeec04e575f2d1aad1fa21ea7684e61fb5"]
+  ],
+  // ...other fields
+}
+```
+
+## Join Request
+
+A user MAY send a `kind 28934` to a relay in order to request admission. It MUST have a `claim` tag containing an invite code. The event's `created_at` MUST be now, plus or minus a few minutes.
+
+```jsonc
+{
+  "kind": 28934,
+  "pubkey": "<user pubkey>",
+  "tags": [
+    ["-"],
+    ["claim", "<invite code>"]
+  ],
+  // ...other fields
+}
+```
+
+Upon receiving a claim, a relay MUST notify the client as to what the status of the claim is using an `OK` message. Failed claims SHOULD use the same standard `"restricted: "` prefix specified by NIP 42.
+
+Relays SHOULD update their `kind 13534` member list and MAY publish a `kind 8000` "add member" event.
+
+Some examples:
+
+```
+["OK", <event-id>, false, "restricted: that invite code is expired."]
+["OK", <event-id>, false, "restricted: that is an invalid invite code."]
+["OK", <event-id>, true, "duplicate: you are already a member of this relay."]
+["OK", <event-id>, true, "info: welcome to wss://relay.bunk.skunk!"]
+```
+
+## Invite Request
+
+Users may request a claim string from a relay by making a request for `kind 28935` events. This event MUST be signed by the pubkey specified in the `self` field of the relay's [NIP 11](./11.md) document.
+
+```jsonc
+{
+  "kind": 28935,
+  "pubkey": "<nip11.self>",
+  "tags": [
+    ["-"],
+    ["claim", "<invite code>"],
+  ],
+  // ...other fields
+}
+```
+
+Note that these events are in the `ephemeral` range, which means relays must explicitly opt-in to this behavior by generating claims on the fly when requested. This allows relays to improve security by issuing a different claim for each request, only issuing claims to certain users, or expiring claims.
+
+## Leave Request
+
+A user MAY send a `kind 28936` to a relay in order to request that their access be revoked. The event's `created_at` MUST be now, plus or minus a few minutes. This event MUST include a [NIP 70](./70.md) `-` tag.
+
+```jsonc
+{
+  "kind": 28936,
+  "tags": [["-"]],
+  // ...other fields
+}
+```
+
+Relays SHOULD update their `kind 13534` member list and MAY publish a `kind 8001` "remove member" event.
+
+## Implementation
+
+Clients MUST only request `kind 28935` events from and send `kind 28934` events to relays which include this NIP in the `supported_nips` section of its [NIP 11](./11.md) relay information document.