nips/43.md

NIP-43
======

Relay Access Requests
---------------------

`draft` `optional`

This NIP defines a way for clients to request admission to relays enforcing
authentication as defined in NIP 42 by signing an ephemeral event.

## Join Request

This NIP defines kind `28934` events which are intended to allow clients to
request admission to a relay. It MUST have a `claim` tag containing an invite
code.

The event's `created_at` MUST be now, plus or minus a few minutes. Clients MAY
send a claim at any time, but MUST check for relay support via NIP 11. This is
to avoid non-compliant relays broadcasting invites to subscribers.

This event should be sent to a relay using the standard `EVENT` verb.

```jsonc
{
  "kind": 28934,
  "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.

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, "claim-ignored: You are already a member of this relay."]
["OK", <event-id>, true, "claim-accepted: 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. These events MUST NOT be considered valid unless signed by the same pubkey
as exists in the relay's NIP 11 document.

```jsonc
{
  "kind": 28935,
  "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.