nips/81.md

NIP-81
======

Relationship Status
-------------------

`draft` `optional`

Event `kind:30382` documents a "Relationship Status" between two pubkeys and uses private and public tags to enhance the description of that relationship. Since statuses change over time, this event is defined as a _parameterized replaceable event_ with a single `d` tag that identifies each pair of keys. 

Optional `n` tags add the target key to unbound lists.

The private tags are JSON Stringified, [NIP-44](44.md)-encrypted and placed inside the `.content` of the event. 

Example of Public Status

```js
{
  "kind": 30382,
  "tags": [
    ["d", "<randomUUID>"],
    ["n", "Clients"],
    ["n", "Developers"],
    ["p", "<pubkey>", "relay"],
    ["trust_level", "1"],
    ["nickname", "<My buddy>"],
    ["summary", "<Summary of the relationship>"]
  ],
  "content": "",
  // ...other fields
}
```

Example of Private Status

```js
{
  "kind": 30382,
  "tags": [
    ["d", "<randomUUID>"],
    ["n", "Clients"],
    ["n", "6064460175057025"], // see private n-tags below
  ],
  "content": nip44Encrypt(JSON.stringify([
    ["p", "<pubkey>", "relay"],
    ["nickname", "<My buddy>"],
    ["summary", "<Summary of the relationship>"],
    ["nip82secret", "<secret used to decrypt medical data for this pubkey>"]
  ])),
  // ...other fields
}
```

`nickname` SHOULD be used instead of the person's display name in all interfaces

Profile screens MAY display the summary of the relationship and allow the user to change the tags of this event.

Clients MAY filter by `kind:30382`, with or without `n` tags, to determine how to assemble feeds, group messages, and when to display content. 

### Private `n`-tags

Clients MAY hide human readable `n`-tags behind a code and list their code maps in the new "Unbound List Names" event kind (`kind:10008`), using the `map` tag from code to name. 

```js
{
  "kind": 10008,
  "content": nip44Encrypt(JSON.stringify([
    ["map", "<Code used in other events>", "<Human readable name>"],
    ["map", "Clients", "Clients"], // public list of my Clients
    ["map", "6064460175057025", "Idiots"] // private list of idiots
  ])),
  // ...other fields
}
```

### Deterministic `d`-Tags. 

For private use cases that must contain deterministic d-Tags, the recommendation is to use [NIP-44](44.md)'s `hkdf` function and use a hash between the user's private key and the pubkey of the `p` tag.

```
nip81_key = hkdf(private_key, salt: 'nip81') 
bobs_d_tag = sha256(nip81_key || bobs_pub)
kates_d_tag = sha256(nip81_key || kates_pub)
```