NIP-39
======

External Identities in Profiles
-------------------------------

`draft` `optional`

## Abstract

Users can declare their control over one or more online identities such as usernames, profile pages, keypairs in kind `10011` using `i` tags.

```jsonc
{
  "kind": 10011,
  "tags": [
    ["i", "github:semisol", "9721ce4ee4fceb91c9711ca2a6c9a5ab"],
    ["i", "twitter:semisol_public", "1619358434134196225"],
    ["i", "mastodon:bitcoinhackers.org/@semisol", "109775066355589974"]
    ["i", "telegram:1087295469", "nostrdirectory/770"]
  ],
  // other fields...
}
```

An `i` tag MUST have two parameters, which are defined as the following:
1. `platform:identity`: This is the platform name (for example `github`) and the identity on that platform (for example `semisol`) joined together with `:`.
2. `proof`: String or object that points to the proof of owning this identity.

Clients SHOULD process any `i` tags with more than 2 values for future extensibility.
Identity provider names SHOULD only include `a-z`, `0-9` and the characters `._-/` and MUST NOT include `:`.
Identity names SHOULD be normalized if possible by replacing uppercase letters with lowercase letters, and if there are multiple aliases for an entity the primary one should be used.

## Claim types

### `github`

Identity: A GitHub username.

Proof: A GitHub Gist ID. This Gist should be created by `<identity>` with a single file that has the text `Verifying that I control the following Nostr public key: <npub encoded public key>`.
This can be located at `https://gist.github.com/<identity>/<proof>`.

### `twitter`

Identity: A Twitter username.

Proof: A Tweet ID. The tweet should be posted by `<identity>` and have the text `Verifying my account on nostr My Public Key: "<npub encoded public key>"`.
This can be located at `https://twitter.com/<identity>/status/<proof>`.

### `mastodon`

Identity: A Mastodon instance and username in the format `<instance>/@<username>`.

Proof: A Mastodon post ID. This post should be published by `<username>@<instance>` and have the text `Verifying that I control the following Nostr public key: "<npub encoded public key>"`.
This can be located at `https://<identity>/<proof>`.

### `telegram`

Identity: A Telegram user ID.

Proof: A string in the format `<ref>/<id>` which points to a message published in the public channel or group with name `<ref>` and message ID `<id>`. This message should be sent by user ID `<identity>` and have the text `Verifying that I control the following Nostr public key: "<npub encoded public key>"`.
This can be located at `https://t.me/<proof>`.