The NOSTR protocol

NOSTR = Notes and Other Stuff Transmitted by Relays

A truly censorship-resistant alternative to Twitter that has a chance of working

Compiled to you by: npub1r26wkhzfw2y8jjvwsf6hghta4f93mqwdrdwjapuj2yydtdqzqc6sclm35s

From: https://github.com/nostr-protocol on 1st of May 2023

If you find this useful you can send me some sats here: ⚡ https://zbd.gg/colaru

NOSTR = Notes and Other Stuff Transmitted by Relays Table of contents nostr - Notes and Other Stuff Transmitted by Relays Very short summary of how it works, if you don't plan to read anything else:This is needed because other solutions are broken:The problem with Twitter The problem with Mastodon and similar programs The problem with SSB (Secure Scuttlebutt)The problem with other solutions that require everybody to run their own server How does Nostr work?How does it solve the problems the networks above can't?FAQ Protocol specification Software License NIPs List Event Kinds Event Kind Ranges Message types Client to Relay Relay to Client Standardized Tags Criteria for acceptance of NIPs License NIP-01 Basic protocol flow description Events and signatures Communication between clients and relays From client to relay: sending events and creating subscriptions From relay to client: sending events and notices Basic Event Kinds Other Notes:NIP-02 Contact List and Petnames Uses Contact list backup Profile discovery and context augmentation Relay sharing Petname scheme NIP-03 OpenTimestamps Attestations for Events NIP-04 Encrypted Direct Message Security Warning Client Implementation Warning NIP-05 Mapping Nostr keys to DNS-based internet identifiers Example Finding users from their NIP-05 identifier Notes Clients must always follow public keys, not NIP-05 addresses Public keys must be in hex format User Discovery implementation suggestion Showing just the domain as an identifier Reasoning for the /.well-known/nostr.json?name=<local-part> format Allowing access from JavaScript apps Security Constraints NIP-06 Basic key derivation from mnemonic seed phrase NIP-07 window.nostr capability for web browsers Implementation NIP-08 Handling Mentions NIP-09 Event Deletion Client Usage Relay Usage Deleting a Deletion NIP-10 On "e" and "p" tags in Text Events (kind 1).Abstract Positional "e" tags (DEPRECATED)Marked "e" tags (PREFERRED)The "p" tag NIP-11 Relay Information Document Field Descriptions Name Description Pubkey Contact Supported NIPs Software Version Extra Fields Server Limitations Event Retention Content Limitations Community Preferences Pay-To-Relay NIP-12 Generic Tag Queries Example Subscription Filter Client Behavior Rationale Suggested Use Cases NIP-13 Proof of Work Mining Example mined note Validating Querying relays for PoW notes Delegated Proof of Work NIP-14 Subject tag in Text events.NIP-15 Nostr Marketplace (for resilient marketplaces)Terms Nostr Marketplace Clients Merchant admin Marketplace Merchant publishing/updating products (event)Event 30017: Create or update a stall.Event 30018: Create or update a product Checkout events Step 1: customer order (event)Step 2: merchant request payment (event)Step 3: merchant verify payment/shipped (event)Customer support events Additional NIP-16 Event Treatment Regular Events Replaceable Events Ephemeral Events Client Behavior Suggested Use Cases NIP-18 Reposts Quote Reposts NIP-19 bech32-encoded entities Bare keys and ids Shareable identifiers with extra metadata Examples Notes NIP-20 Command Results Examples Client Handling Future Extensions NIP-21 nostr: URL scheme Examples NIP-22 Event created_at Limits Client Behavior Motivation Python (pseudocode) Example NIP-23 Long-form Content Format Metadata Editability Linking References Example Event NIP-25 Reactions Tags NIP: 26 Delegated Event Signing Introducing the 'delegation' tag Delegation Token Conditions Query String Example Relay & Client Support NIP-27 Text Note References Example of a profile mention process Verbose and probably unnecessary considerations NIP-28 Public Chat Kind 40: Create channel Kind 41: Set channel metadata Kind 42: Create channel message Kind 43: Hide message Kind 44: Mute user NIP-10 relay recommendations Motivation Additional info NIP-33 Parameterized Replaceable Events Implementation Referencing and tagging Client Behavior NIP-36 Sensitive Content / Content Warning Spec Example NIP-39 External Identities in Profiles Abstract i tag on a metadata event Claim types github twitter mastodon telegram NIP-40 Expiration Timestamp Spec Example Client Behavior Relay Behavior Suggested Use Cases Warning NIP-42 Authentication of clients to relays Motivation Definitions Protocol flow Signed Event Verification NIP-45 Event Counts Motivation Filters and return values NIP-46 Nostr Connect Rationale Terms TL;DR Signer Protocol Messages Request Response Methods Mandatory optional Nostr Connect URI JavaScript Example Flows Connect Disconnect (from App)Disconnect (from Signer)Get Public Key Sign Event Delegate NIP-50 Search Capability Abstract search filter field Extensions NIP-51 Lists Replaceable List Event Example Parameterized Replaceable List Event Example List Event Kinds Mute List Pin List Categorized People List Categorized Bookmarks List NIP-56 Reporting Tags Example events Client behavior Relay behavior NIP-57 Lightning Zaps Protocol flow Reference and examples Appendix A: Zap Request Event Appendix B: Zap Request HTTP Request Appendix C: LNURL Server Configuration Appendix D: LNURL Server Zap Request Validation Appendix E: Zap Receipt Event Appendix F: Validating Zap Receipts Appendix G: zap tag on zapped event Future Work NIP-58 Badges Badge Definition event Badge Award event Profile Badges Event Motivation Recommendations Example of a Badge Definition event Example of Badge Award event Example of a Profile Badges event NIP-65 Relay List Metadata The meaning of read and write Motivation Purposes Suggestions Why not in kind 0 Metadata Example NIP-78 Arbitrary custom app data Nostr event Some use cases NIP-94 File Metadata Event format Suggested use cases

nostr - Notes and Other Stuff Transmitted by Relays

The simplest open protocol that is able to create a censorship-resistant global "social" network once and for all.

It doesn't rely on any trusted central server, hence it is resilient; it is based on cryptographic keys and signatures, so it is tamperproof; it does not rely on P2P techniques, and therefore it works.

This is a work in progress. Join the Telegram group!

Very short summary of how it works, if you don't plan to read anything else:

Everybody runs a client. It can be a native client, a web client, etc. To publish something, you write a post, sign it with your key and send it to multiple relays (servers hosted by someone else, or yourself). To get updates from other people, you ask multiple relays if they know anything about these other people. Anyone can run a relay. A relay is very simple and dumb. It does nothing besides accepting posts from some people and forwarding to others. Relays don't have to be trusted. Signatures are verified on the client side.

How to start using Nostr

Nostr client feature comparison

List of projects built on Nostr

This is needed because other solutions are broken:

The problem with Twitter

Twitter has ads;

Twitter uses bizarre techniques to keep you addicted;

Twitter doesn't show an actual historical feed from people you follow;

Twitter bans people;

Twitter shadowbans people;

Twitter has a lot of spam.

The problem with Mastodon and similar programs

User identities are attached to domain names controlled by third-parties;

Server owners can ban you, just like Twitter; Server owners can also block other servers;

Migration between servers is an afterthought and can only be accomplished if servers cooperate. It doesn't work in an adversarial environment (all followers are lost);

There are no clear incentives to run servers, therefore, they tend to be run by enthusiasts and people who want to have their name attached to a cool domain. Then, users are subject to the despotism of a single person, which is often worse than that of a big company like Twitter, and they can't migrate out;

Since servers tend to be run amateurishly, they are often abandoned after a while — which is effectively the same as banning everybody;

It doesn't make sense to have a ton of servers if updates from every server will have to be painfully pushed (and saved!) to a ton of other servers. This point is exacerbated by the fact that servers tend to exist in huge numbers, therefore more data has to be passed to more places more often;

For the specific example of video sharing, ActivityPub enthusiasts realized it would be completely impossible to transmit video from server to server the way text notes are, so they decided to keep the video hosted only from the single instance where it was posted to, which is similar to the Nostr approach.

The problem with SSB (Secure Scuttlebutt)

It doesn't have many problems. I think it's great. I was going to use it as a basis for this, but

its protocol is too complicated because it wasn't thought about being an open protocol at all. It was just written in JavaScript in probably a quick way to solve a specific problem and grew from that, therefore it has weird and unnecessary quirks like signing a JSON string which must strictly follow the rules of ECMA-262 6th Edition;

It insists on having a chain of updates from a single user, which feels unnecessary to me and something that adds bloat and rigidity to the thing — each server/user needs to store all the chain of posts to be sure the new one is valid. Why? (Maybe they have a good reason);

It is not as simple as Nostr, as it was primarily made for P2P syncing, with "pubs" being an afterthought;

Still, it may be worth considering using SSB instead of this custom protocol and just adapting it to the client-relay server model, because reusing a standard is always better than trying to get people in a new one.

The problem with other solutions that require everybody to run their own server

They require everybody to run their own server;

Sometimes people can still be censored in these because domain names can be censored.

How does Nostr work?

There are two components: clients and relays. Each user runs a client. Anyone can run a relay.

Every user is identified by a public key. Every post is signed. Every client validates these signatures.

Clients fetch data from relays of their choice and publish data to other relays of their choice. A relay doesn't talk to another relay, only directly to users.

For example, to "follow" someone a user just instructs their client to query the relays it knows for posts from that public key.

On startup, a client queries data from all relays it knows for all users it follows (for example, all updates from the last day), then displays that data to the user chronologically.

A "post" can contain any kind of structured data, but the most used ones are going to find their way into the standard so all clients and relays can handle them seamlessly.

How does it solve the problems the networks above can't?

Users getting banned and servers being closed

A relay can block a user from publishing anything there, but that has no effect on them as they can still publish to other relays. Since users are identified by a public key, they don't lose their identities and their follower base when they get banned.
Instead of requiring users to manually type new relay addresses (although this should also be supported), whenever someone you're following posts a server recommendation, the client should automatically add that to the list of relays it will query.
If someone is using a relay to publish their data but wants to migrate to another one, they can publish a server recommendation to that previous relay and go;
If someone gets banned from many relays such that they can't get their server recommendations broadcasted, they may still let some close friends know through other means with which relay they are publishing now. Then, these close friends can publish server recommendations to that new server, and slowly, the old follower base of the banned user will begin finding their posts again from the new relay.
All of the above is valid too for when a relay ceases its operations.

Censorship-resistance

Each user can publish their updates to any number of relays.
A relay can charge a fee (the negotiation of that fee is outside of the protocol for now) from users to publish there, which ensures censorship-resistance (there will always be some Russian server willing to take your money in exchange for serving your posts).

Spam

If spam is a concern for a relay, it can require payment for publication or some other form of authentication, such as an email address or phone, and associate these internally with a pubkey that then gets to publish to that relay — or other anti-spam techniques, like hashcash or captchas. If a relay is being used as a spam vector, it can easily be unlisted by clients, which can continue to fetch updates from other relays.

Data storage

For the network to stay healthy, there is no need for hundreds of active relays. In fact, it can work just fine with just a handful, given the fact that new relays can be created and spread through the network easily in case the existing relays start misbehaving. Therefore, the amount of data storage required, in general, is relatively less than Mastodon or similar software.
Or considering a different outcome: one in which there exist hundreds of niche relays run by amateurs, each relaying updates from a small group of users. The architecture scales just as well: data is sent from users to a single server, and from that server directly to the users who will consume that. It doesn't have to be stored by anyone else. In this situation, it is not a big burden for any single server to process updates from others, and having amateur servers is not a problem.

Video and other heavy content

It's easy for a relay to reject large content, or to charge for accepting and hosting large content. When information and incentives are clear, it's easy for the market forces to solve the problem.

Techniques to trick the user

Each client can decide how to best show posts to users, so there is always the option of just consuming what you want in the manner you want — from using an AI to decide the order of the updates you'll see to just reading them in chronological order.

FAQ

This is very simple. Why hasn't anyone done it before?

I don't know, but I imagine it has to do with the fact that people making social networks are either companies wanting to make money or P2P activists who want to make a thing completely without servers. They both fail to see the specific mix of both worlds that Nostr uses.

How do I find people to follow?

First, you must know them and get their public key somehow, either by asking or by seeing it referenced somewhere. Once you're inside a Nostr social network you'll be able to see them interacting with other people and then you can also start following and interacting with these others.

How do I find relays? What happens if I'm not connected to the same relays someone else is?

You won't be able to communicate with that person. But there are hints on events that can be used so that your client software (or you, manually) knows how to connect to the other person's relay and interact with them. There are other ideas on how to solve this too in the future but we can't ever promise perfect reachability, no protocol can.

Can I know how many people are following me?

No, but you can get some estimates if relays cooperate in an extra-protocol way.

What incentive is there for people to run relays?

The question is misleading. It assumes that relays are free dumb pipes that exist such that people can move data around through them. In this case yes, the incentives would not exist. This in fact could be said of DHT nodes in all other p2p network stacks: what incentive is there for people to run DHT nodes?

Nostr enables you to move between server relays or use multiple relays but if these relays are just on AWS or Azure what’s the difference?

There are literally thousands of VPS providers scattered all around the globe today, there is not only AWS or Azure. AWS or Azure are exactly the providers used by single centralized service providers that need a lot of scale, and even then not just these two. For smaller relay servers any VPS will do the job very well.

Protocol specification

See the NIPs and especially NIP-01 for a reasonably-detailed explanation of the protocol spec (hint: it is very short and simple).

Software

There is a list of most software being built using Nostr on https://github.com/aljazceru/awesome-nostr that seemed to be almost complete last time I looked.

License

Public domain.

NIPs

NIPs stand for Nostr Implementation Possibilities. They exist to document what may be implemented by Nostr-compatible relay and client software.

List

Event Kinds

Event Kind Ranges

Message Types

Standardized Tags

Criteria for acceptance of NIPs

License

List

NIP-01: Basic protocol flow description

NIP-02: Contact List and Petnames

NIP-03: OpenTimestamps Attestations for Events

NIP-04: Encrypted Direct Message

NIP-05: Mapping Nostr keys to DNS-based internet identifiers

NIP-06: Basic key derivation from mnemonic seed phrase

NIP-07: window.nostr capability for web browsers

NIP-08: Handling Mentions --- unrecommended: deprecated in favor of NIP-27

NIP-09: Event Deletion

NIP-10: Conventions for clients' use of e and p tags in text events

NIP-11: Relay Information Document

NIP-12: Generic Tag Queries

NIP-13: Proof of Work

NIP-14: Subject tag in text events.

NIP-15: Nostr Marketplace (for resilient marketplaces)

NIP-16: Event Treatment

NIP-18: Reposts

NIP-19: bech32-encoded entities

NIP-20: Command Results

NIP-21: nostr: URL scheme

NIP-22: Event created_at Limits

NIP-23: Long-form Content

NIP-25: Reactions

NIP-26: Delegated Event Signing

NIP-27: Text Note References

NIP-28: Public Chat

NIP-33: Parameterized Replaceable Events

NIP-36: Sensitive Content

NIP-39: External Identities in Profiles

NIP-40: Expiration Timestamp

NIP-42: Authentication of clients to relays

NIP-45: Counting results

NIP-46: Nostr Connect

NIP-50: Keywords filter

NIP-51: Lists

NIP-56: Reporting

NIP-57: Lightning Zaps

NIP-58: Badges

NIP-65: Relay List Metadata

NIP-78: Application-specific data

NIP-94: File Metadata

Event Kinds

kind	description	NIP
`0`	Metadata	1
`1`	Short Text Note	1
`2`	Recommend Relay	1
`3`	Contacts	2
`4`	Encrypted Direct Messages	4
`5`	Event Deletion	9
`6`	Reposts	18
`7`	Reaction	25
`8`	Badge Award	58
`40`	Channel Creation	28
`41`	Channel Metadata	28
`42`	Channel Message	28
`43`	Channel Hide Message	28
`44`	Channel Mute User	28
`1063`	File Metadata	94
`1984`	Reporting	56
`9734`	Zap Request	57
`9735`	Zap	57
`10000`	Mute List	51
`10001`	Pin List	51
`10002`	Relay List Metadata	65
`22242`	Client Authentication	42
`24133`	Nostr Connect	46
`30000`	Categorized People List	51
`30001`	Categorized Bookmark List	51
`30008`	Profile Badges	58
`30009`	Badge Definition	58
`30017`	Create or update a stall	15
`30018`	Create or update a product	15
`30023`	Long-form Content	23
`30078`	Application-specific Data	78

Event Kind Ranges

range	description	NIP
`1000`--`9999`	Regular Events	16
`10000`--`19999`	Replaceable Events	16
`20000`--`29999`	Ephemeral Events	16
`30000`--`39999`	Parameterized Replaceable Events	33

Message types

Client to Relay

type	description	NIP
`AUTH`	used to send authentication events	42
`CLOSE`	used to stop previous subscriptions	1
`COUNT`	used to request event counts	45
`EVENT`	used to publish events	1
`REQ`	used to request events and subscribe to new updates	1

Relay to Client

type	description	NIP
`AUTH`	used to send authentication challenges	42
`COUNT`	used to send requested event counts to clients	45
`EOSE`	used to notify clients all stored events have been sent	1
`EVENT`	used to send events requested to clients	1
`NOTICE`	used to send human-readable messages to clients	1
`OK`	used to notify clients if an EVENT was successful	20

Please update these lists when proposing NIPs introducing new event kinds.

When experimenting with kinds, keep in mind the classification introduced by NIP-16 and NIP-33.

Standardized Tags

name	value	other parameters	NIP
`a`	coordinates to an event	relay URL	33, 23
`d`	identifier	--	33
`e`	event id (hex)	relay URL, marker	1, 10
`g`	geohash	--	12
`i`	identity	proof	39
`p`	pubkey (hex)	relay URL	1
`r`	a reference (URL, etc)	--	12
`t`	hashtag	--	12
`amount`	millisats	--	57
`bolt11`	`bolt11` invoice	--	57
`challenge`	challenge string	--	42
`content-warning`	reason	--	36
`delegation`	pubkey, conditions, delegation token	--	26
`description`	badge description	--	58
`description`	invoice description	--	57
`expiration`	unix timestamp (string)	--	40
`image`	image URL	dimensions in pixels	23, 58
`lnurl`	`bech32` encoded `lnurl`	--	57
`name`	badge name	--	58
`nonce`	random	--	13
`preimage`	hash of `bolt11` invoice	--	57
`published_at`	unix timestamp (string)	--	23
`relay`	relay url	--	42
`relays`	relay list	--	57
`subject`	subject	--	14
`summary`	article summary	--	23
`thumb`	badge thumbnail	dimensions in pixels	58
`title`	article title	--	23
`zap`	profile name	type of value	57

Criteria for acceptance of NIPs

They should be implemented in at least two clients and one relay -- when applicable.

They should make sense.

They should be optional and backwards-compatible: care must be taken such that clients and relays that choose to not implement them do not stop working when interacting with the ones that choose to.

There should be no more than one way of doing the same thing.

Other rules will be made up when necessary.

License

All NIPs are public domain.

NIP-01

Basic protocol flow description

draft mandatory author:fiatjaf author:distbit author:scsibug author:kukks author:jb55 author:semisol

This NIP defines the basic protocol that should be implemented by everybody. New NIPs may add new optional (or mandatory) fields and messages and features to the structures and flows described here.

Events and signatures

Each user has a keypair. Signatures, public key, and encodings are done according to the Schnorr signatures standard for the curve secp256k1.

The only object type that exists is the event, which has the following format on the wire:

{
  "id": <32-bytes lowercase hex-encoded sha256 of the serialized event data>
  "pubkey": <32-bytes lowercase hex-encoded public key of the event creator>,
  "created_at": <unix timestamp in seconds>,
  "kind": <integer>,
  "tags": [
    ["e", <32-bytes hex of the id of another event>, <recommended relay URL>],
    ["p", <32-bytes hex of a pubkey>, <recommended relay URL>],
    ... // other kinds of tags may be included later
  ],
  "content": <arbitrary string>,
  "sig": <64-bytes hex of the signature of the sha256 hash of the serialized event data, which is the same as the "id" field>
}

To obtain the event.id, we sha256 the serialized event. The serialization is done over the UTF-8 JSON-serialized string (with no white space or line breaks) of the following structure:

[
  0,
  <pubkey, as a (lowercase) hex string>,
  <created_at, as a number>,
  <kind, as a number>,
  <tags, as an array of arrays of non-null strings>,
  <content, as a string>
]

Communication between clients and relays

Relays expose a websocket endpoint to which clients can connect.

From client to relay: sending events and creating subscriptions

Clients can send 3 types of messages, which must be JSON arrays, according to the following patterns:

["EVENT", <event JSON as defined above>], used to publish events.

["REQ", <subscription_id>, <filters JSON>...], used to request events and subscribe to new updates.

["CLOSE", <subscription_id>], used to stop previous subscriptions.

<subscription_id> is an arbitrary, non-empty string of max length 64 chars, that should be used to represent a subscription.

<filters> is a JSON object that determines what events will be sent in that subscription, it can have the following attributes:

{
  "ids": <a list of event ids or prefixes>,
  "authors": <a list of pubkeys or prefixes, the pubkey of an event must be one of these>,
  "kinds": <a list of a kind numbers>,
  "#e": <a list of event ids that are referenced in an "e" tag>,
  "#p": <a list of pubkeys that are referenced in a "p" tag>,
  "since": <an integer unix timestamp, events must be newer than this to pass>,
  "until": <an integer unix timestamp, events must be older than this to pass>,
  "limit": <maximum number of events to be returned in the initial query>
}

Upon receiving a REQ message, the relay SHOULD query its internal database and return events that match the filter, then store that filter and send again all future events it receives to that same websocket until the websocket is closed. The CLOSE event is received with the same <subscription_id> or a new REQ is sent using the same <subscription_id>, in which case it should overwrite the previous subscription.

Filter attributes containing lists (such as ids, kinds, or #e) are JSON arrays with one or more values. At least one of the array's values must match the relevant field in an event for the condition itself to be considered a match. For scalar event attributes such as kind, the attribute from the event must be contained in the filter list. For tag attributes such as #e, where an event may have multiple values, the event and filter condition values must have at least one item in common.

The ids and authors lists contain lowercase hexadecimal strings, which may either be an exact 64-character match, or a prefix of the event value. A prefix match is when the filter string is an exact string prefix of the event value. The use of prefixes allows for more compact filters where a large number of values are queried, and can provide some privacy for clients that may not want to disclose the exact authors or events they are searching for.

All conditions of a filter that are specified must match for an event for it to pass the filter, i.e., multiple conditions are interpreted as && conditions.

A REQ message may contain multiple filters. In this case, events that match any of the filters are to be returned, i.e., multiple filters are to be interpreted as || conditions.

The limit property of a filter is only valid for the initial query and can be ignored afterward. When limit: n is present it is assumed that the events returned in the initial query will be the latest n events. It is safe to return less events than limit specifies, but it is expected that relays do not return (much) more events than requested so clients don't get unnecessarily overwhelmed by data.

From relay to client: sending events and notices

Relays can send 3 types of messages, which must also be JSON arrays, according to the following patterns:

["EVENT", <subscription_id>, <event JSON as defined above>], used to send events requested by clients.

["EOSE", <subscription_id>], used to indicate the end of stored events and the beginning of events newly received in real-time.

["NOTICE", <message>], used to send human-readable error messages or other things to clients.

This NIP defines no rules for how NOTICE messages should be sent or treated.

EVENT messages MUST be sent only with a subscription ID related to a subscription previously initiated by the client (using the REQ message above).

Basic Event Kinds

0: set_metadata: the content is set to a stringified JSON object {name: <username>, about: <string>, picture: <url, string>} describing the user who created the event. A relay may delete past set_metadata events once it gets a new one for the same pubkey.

1: text_note: the content is set to the plaintext content of a note (anything the user wants to say). Markdown links ([]() stuff) are not plaintext.

2: recommend_server: the content is set to the URL (e.g., wss://somerelay.com) of a relay the event creator wants to recommend to its followers.

A relay may choose to treat different message kinds differently, and it may or may not choose to have a default way to handle kinds it doesn't know about.

Other Notes:

Clients should not open more than one websocket to each relay. One channel can support an unlimited number of subscriptions, so clients should do that.

The tags array can store a tag identifier as the first element of each subarray, plus arbitrary information afterward (always as strings). This NIP defines "p" — meaning "pubkey", which points to a pubkey of someone that is referred to in the event —, and "e" — meaning "event", which points to the id of an event this event is quoting, replying to or referring to somehow. See NIP-10 for a detailed description of "e" and "p" tags.

The <recommended relay URL> item present on the "e" and "p" tags is an optional (could be set to "") URL of a relay the client could attempt to connect to fetch the tagged event or other events from a tagged profile. It MAY be ignored, but it exists to increase censorship resistance and make the spread of relay addresses more seamless across clients.

NIP-02

Contact List and Petnames

final optional author:fiat7jaf author:arcbtc

A special event with kind 3, meaning "contact list" is defined as having a list of p tags, one for each of the followed/known profiles one is following.

Each tag entry should contain the key for the profile, a relay URL where events from that key can be found (can be set to an empty string if not needed), and a local name (or "petname") for that profile (can also be set to an empty string or not provided), i.e., ["p", <32-bytes hex key>, <main relay URL>, <petname>]. The content can be anything and should be ignored.

For example:

{
  "kind": 3,
  "tags": [
    ["p", "91cf9..4e5ca", "wss://alicerelay.com/", "alice"],
    ["p", "14aeb..8dad4", "wss://bobrelay.com/nostr", "bob"],
    ["p", "612ae..e610f", "ws://carolrelay.com/ws", "carol"]
  ],
  "content": "",
  ...other fields
}

Every new contact list that gets published overwrites the past ones, so it should contain all entries. Relays and clients SHOULD delete past contact lists as soon as they receive a new one.

Uses

Contact list backup

If one believes a relay will store their events for sufficient time, they can use this kind-3 event to backup their following list and recover on a different device.

Profile discovery and context augmentation

A client may rely on the kind-3 event to display a list of followed people by profiles one is browsing; make lists of suggestions on who to follow based on the contact lists of other people one might be following or browsing; or show the data in other contexts.

A client may publish a full list of contacts with good relays for each of their contacts so other clients may use these to update their internal relay lists if needed, increasing censorship-resistance.

Petname scheme

The data from these contact lists can be used by clients to construct local "petname" tables derived from other people's contact lists. This alleviates the need for global human-readable names. For example:

A user has an internal contact list that says

[
  ["p", "21df6d143fb96c2ec9d63726bf9edc71", "", "erin"]
]

And receives two contact lists, one from 21df6d143fb96c2ec9d63726bf9edc71 that says

[
  ["p", "a8bb3d884d5d90b413d9891fe4c4e46d", "", "david"]
]

and another from a8bb3d884d5d90b413d9891fe4c4e46d that says

[
  ["p", "f57f54057d2a7af0efecc8b0b66f5708", "", "frank"]
]

When the user sees 21df6d143fb96c2ec9d63726bf9edc71 the client can show erin instead; When the user sees a8bb3d884d5d90b413d9891fe4c4e46d the client can show david.erin instead; When the user sees f57f54057d2a7af0efecc8b0b66f5708 the client can show frank.david.erin instead.

NIP-03

OpenTimestamps Attestations for Events

draft optional author:fiatjaf

When there is an OTS available it MAY be included in the existing event body under the ots key:

{
  "id": ...,
  "kind": ...,
  ...,
  ...,
  "ots": <base64-encoded OTS file data>
}

The event id MUST be used as the raw hash to be included in the OpenTimestamps merkle tree.

The attestation can be either provided by relays automatically (and the OTS binary contents just appended to the events it receives) or by clients themselves when they first upload the event to relays — and used by clients to show that an event is really "at least as old as [OTS date]".

NIP-04

Encrypted Direct Message

final optional author:arcbtc

A special event with kind 4, meaning "encrypted direct message". It is supposed to have the following attributes:

content MUST be equal to the base64-encoded, aes-256-cbc encrypted string of anything a user wants to write, encrypted using a shared cipher generated by combining the recipient's public-key with the sender's private-key; this appended by the base64-encoded initialization vector as if it was a querystring parameter named "iv". The format is the following: "content": "<encrypted_text>?iv=<initialization_vector>".

tags MUST contain an entry identifying the receiver of the message (such that relays may naturally forward this event to them), in the form ["p", "<pubkey, as a hex string>"].

tags MAY contain an entry identifying the previous message in a conversation or a message we are explicitly replying to (such that contextual, more organized conversations may happen), in the form ["e", "<event_id>"].

Note: By default in the libsecp256k1 ECDH implementation, the secret is the SHA256 hash of the shared point (both X and Y coordinates). In Nostr, only the X coordinate of the shared point is used as the secret and it is NOT hashed. If using libsecp256k1, a custom function that copies the X coordinate must be passed as the hashfp argument in secp256k1_ecdh. See here.

Code sample for generating such an event in JavaScript:

import crypto from 'crypto'
import * as secp from '@noble/secp256k1'

let sharedPoint = secp.getSharedSecret(ourPrivateKey, '02' + theirPublicKey)
let sharedX = sharedPoint.slice(1, 33)

let iv = crypto.randomFillSync(new Uint8Array(16))
var cipher = crypto.createCipheriv(
  'aes-256-cbc',
  Buffer.from(sharedX),
  iv
)
let encryptedMessage = cipher.update(text, 'utf8', 'base64')
encryptedMessage += cipher.final('base64')
let ivBase64 = Buffer.from(iv.buffer).toString('base64')

let event = {
  pubkey: ourPubKey,
  created_at: Math.floor(Date.now() / 1000),
  kind: 4,
  tags: [['p', theirPublicKey]],
  content: encryptedMessage + '?iv=' + ivBase64
}

Security Warning

This standard does not go anywhere near what is considered the state-of-the-art in encrypted communication between peers, and it leaks metadata in the events, therefore it must not be used for anything you really need to keep secret, and only with relays that use AUTH to restrict who can fetch your kind:4 events.

Client Implementation Warning

Clients should not search and replace public key or note references from the .content. If processed like a regular text note (where @npub... is replaced with #[0] with a ["p", "..."] tag) the tags are leaked and the mentioned user will receive the message in their inbox.

NIP-05

Mapping Nostr keys to DNS-based internet identifiers

final optional author:fiatjaf author:mikedilger

On events of kind 0 (set_metadata) one can specify the key "nip05" with an internet identifier (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 hex formatted 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:

{
  "pubkey": "b0635d6a9851d3aed0cd6c495b282167acf761729078d975fc341b22650b07b9",
  "kind": 0,
  "content": "{\"name\": \"bob\", \"nip05\": \"[email protected]\"}"...
}

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

{
  "names": {
    "bob": "b0635d6a9851d3aed0cd6c495b282167acf761729078d975fc341b22650b07b9"
  }
}

or with the optional "relays" attribute:

{
  "names": {
    "bob": "b0635d6a9851d3aed0cd6c495b282167acf761729078d975fc341b22650b07b9"
  },
  "relays": {
    "b0635d6a9851d3aed0cd6c495b282167acf761729078d975fc341b22650b07b9": [ "wss://relay.example.com", "wss://relay2.example.com" ]
  }
}

If the pubkey matches the one given in "names" (as in the example above) that means the association is right and the "nip05" identifier is valid and can be displayed.

The optional "relays" attribute may contain an object with public keys as properties and arrays of relay URLs as values. When present, that can be used to help clients learn in which relays that user may be found. Web servers which serve /.well-known/nostr.json files dynamically based on the query string SHOULD also serve the relays data for any name they serve in the same reply when that is available.

Finding users from their NIP-05 identifier

A client may implement support for finding users' public keys from internet identifiers, the flow is the same as above, but reversed: first the client fetches the well-known URL and from there it gets the public key of the user, then it tries to fetch the kind 0 event for that user and check if it has a matching "nip05".

Notes

Clients must always follow public keys, not NIP-05 addresses

For example, if after finding that [email protected] has the public key abc...def, the user clicks a button to follow that profile, the client must keep a primary reference to abc...def, not [email protected]. If, for any reason, the address https://bob.com/.well-known/nostr.json?name=bob starts returning the public key 1d2...e3f at any time in the future, the client must not replace abc...def in his list of followed profiles for the user (but it should stop displaying "[email protected]" for that user, as that will have become an invalid "nip05" property).

Public keys must be in hex format

Keys must be returned in hex format. Keys in NIP-19 npub format are only meant to be used for display in client UIs, not in this NIP.

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 "[email protected]" 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 [email protected] as that is redundant. Instead, Bob can use the identifier [email protected] 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.

Allowing access from JavaScript apps

JavaScript Nostr apps may be restricted by browser CORS policies that prevent them from accessing /.well-known/nostr.json on the user's domain. When CORS prevents JS from loading a resource, the JS program sees it as a network failure identical to the resource not existing, so it is not possible for a pure-JS app to tell the user for certain that the failure was caused by a CORS issue. JS Nostr apps that see network failures requesting /.well-known/nostr.json files may want to recommend to users that they check the CORS policy of their servers, e.g.:

$ curl -sI https://example.com/.well-known/nostr.json?name=bob | grep -i ^Access-Control
Access-Control-Allow-Origin: *

Users should ensure that their /.well-known/nostr.json is served with the HTTP header Access-Control-Allow-Origin: * to ensure it can be validated by pure JS apps running in modern browsers.

Security Constraints

The /.well-known/nostr.json endpoint MUST NOT return any HTTP redirects.

Fetchers MUST ignore any HTTP redirects given by the /.well-known/nostr.json endpoint.

NIP-06

Basic key derivation from mnemonic seed phrase

draft optional author:fiatjaf

BIP39 is used to generate mnemonic seed words and derive a binary seed from them.

BIP32 is used to derive the path m/44'/1237'/<account>'/0/0 (according to the Nostr entry on SLIP44).

A basic client can simply use an account of 0 to derive a single key. For more advanced use-cases you can increment account, allowing generation of practically infinite keys from the 5-level path with hardened derivation.

Other types of clients can still get fancy and use other derivation paths for their own other purposes.

NIP-07

`window.nostr` capability for web browsers

draft optional author:fiatjaf

The window.nostr object may be made available by web browsers or extensions and websites or web-apps may make use of it after checking its availability.

That object must define the following methods:

async window.nostr.getPublicKey(): string // returns a public key as hex
async window.nostr.signEvent(event: Event): Event // takes an event object, adds `id`, `pubkey` and `sig` and returns it

Aside from these two basic above, the following functions can also be implemented optionally:

async window.nostr.getRelays(): { [url: string]: {read: boolean, write: boolean} } // returns a basic map of relay urls to relay policies
async window.nostr.nip04.encrypt(pubkey, plaintext): string // returns ciphertext and iv as specified in nip-04
async window.nostr.nip04.decrypt(pubkey, ciphertext): string // takes ciphertext and iv as specified in nip-04

Implementation

horse (Chrome and derivatives)

nos2x (Chrome and derivatives)

Alby (Chrome and derivatives, Firefox, Safari)

Blockcore (Chrome and derivatives)

nos2x-fox (Firefox)

Flamingo (Chrome and derivatives)

Warning unrecommended: deprecated in favor of NIP-27

NIP-08

Handling Mentions

final unrecommended optional author:fiatjaf author:scsibug

This document standardizes the treatment given by clients of inline mentions of other events and pubkeys inside the content of text_notes.

Clients that want to allow tagged mentions they MUST show an autocomplete component or something analogous to that whenever the user starts typing a special key (for example, "@") or presses some button to include a mention etc -- or these clients can come up with other ways to unambiguously differentiate between mentions and normal text.

Once a mention is identified, for example, the pubkey 27866e9d854c78ae625b867eefdfa9580434bc3e675be08d2acb526610d96fbe, the client MUST add that pubkey to the .tags with the tag p, then replace its textual reference (inside .content) with the notation #[index] in which "index" is equal to the 0-based index of the related tag in the tags array.

The same process applies for mentioning event IDs.

A client that receives a text_note event with such #[index] mentions in its .content CAN do a search-and-replace using the actual contents from the .tags array with the actual pubkey or event ID that is mentioned, doing any desired context augmentation (for example, linking to the pubkey or showing a preview of the mentioned event contents) it wants in the process.

Where #[index] has an index that is outside the range of the tags array or points to a tag that is not an e or p tag or a tag otherwise declared to support this notation, the client MUST NOT perform such replacement or augmentation, but instead display it as normal text.

NIP-09

Event Deletion

draft optional author:scsibug

A special event with kind 5, meaning "deletion" is defined as having a list of one or more e tags, each referencing an event the author is requesting to be deleted.

Each tag entry must contain an "e" event id intended for deletion.

The event's content field MAY contain a text note describing the reason for the deletion.

For example:

{
  "kind": 5,
  "pubkey": <32-bytes hex-encoded public key of the event creator>,
  "tags": [
    ["e", "dcd59..464a2"],
    ["e", "968c5..ad7a4"],
  ],
  "content": "these posts were published by accident",
  ...other fields
}

Relays SHOULD delete or stop publishing any referenced events that have an identical pubkey as the deletion request. Clients SHOULD hide or otherwise indicate a deletion status for referenced events.

Relays SHOULD continue to publish/share the deletion events indefinitely, as clients may already have the event that's intended to be deleted. Additionally, clients SHOULD broadcast deletion events to other relays which don't have it.

Client Usage

Clients MAY choose to fully hide any events that are referenced by valid deletion events. This includes text notes, direct messages, or other yet-to-be defined event kinds. Alternatively, they MAY show the event along with an icon or other indication that the author has "disowned" the event. The content field MAY also be used to replace the deleted events' own content, although a user interface should clearly indicate that this is a deletion reason, not the original content.

A client MUST validate that each event pubkey referenced in the e tag of the deletion request is identical to the deletion request pubkey, before hiding or deleting any event. Relays can not, in general, perform this validation and should not be treated as authoritative.

Clients display the deletion event itself in any way they choose, e.g., not at all, or with a prominent notice.

Relay Usage

Relays MAY validate that a deletion event only references events that have the same pubkey as the deletion itself, however this is not required since relays may not have knowledge of all referenced events.

Deleting a Deletion

Publishing a deletion event against a deletion has no effect. Clients and relays are not obliged to support "undelete" functionality.

NIP-10

On "e" and "p" tags in Text Events (kind 1).

draft optional author:unclebobmartin

Abstract

This NIP describes how to use "e" and "p" tags in text events, especially those that are replies to other text events. It helps clients thread the replies into a tree rooted at the original event.

Positional "e" tags (DEPRECATED)

This scheme is in common use; but should be considered deprecated.

["e", <event-id>, <relay-url>] as per NIP-01.

Where:

<event-id> is the id of the event being referenced.

<relay-url> is the URL of a recommended relay associated with the reference. Many clients treat this field as optional.

The positions of the "e" tags within the event denote specific meanings as follows:

No "e" tag:

This event is not a reply to, nor does it refer to, any other event.

One "e" tag:

["e", <id>]: The id of the event to which this event is a reply.

Two "e" tags: ["e", <root-id>], ["e", <reply-id>]

<root-id> is the id of the event at the root of the reply chain. <reply-id> is the id of the article to which this event is a reply.

Many "e" tags: ["e", <root-id>] ["e", <mention-id>], ..., ["e", <reply-id>]

There may be any number of <mention-ids>. These are the ids of events which may, or may not be in the reply chain.

They are citings from this event. root-id and reply-id are as above.

This scheme is deprecated because it creates ambiguities that are difficult, or impossible to resolve when an event references another but is not a reply.

Marked "e" tags (PREFERRED)

["e", <event-id>, <relay-url>, <marker>]

Where:

<event-id> is the id of the event being referenced.

<relay-url> is the URL of a recommended relay associated with the reference. Clients SHOULD add a valid <relay-URL> field, but may instead leave it as "".

<marker> is optional and if present is one of "reply", "root", or "mention".

The order of marked "e" tags is not relevant. Those marked with "reply" denote the id of the reply event being responded to. Those marked with "root" denote the root id of the reply thread being responded to. For top level replies (those replying directly to the root event), only the "root" marker should be used. Those marked with "mention" denote a quoted or reposted event id.

A direct reply to the root of a thread should have a single marked "e" tag of type "root".

This scheme is preferred because it allows events to mention others without confusing them with <reply-id> or <root-id>.

The "p" tag

Used in a text event contains a list of pubkeys used to record who is involved in a reply thread.

When replying to a text event E the reply event's "p" tags should contain all of E's "p" tags as well as the "pubkey" of the event being replied to.

Example: Given a text event authored by a1 with "p" tags [p1, p2, p3] then the "p" tags of the reply should be [a1, p1, p2, p3] in no particular order.

NIP-11

Relay Information Document

draft optional author:scsibug author:doc-hex author:cameri

Relays may provide server metadata to clients to inform them of capabilities, administrative contacts, and various server attributes. This is made available as a JSON document over HTTP, on the same URI as the relay's websocket.

When a relay receives an HTTP(s) request with an Accept header of application/nostr+json to a URI supporting WebSocket upgrades, they SHOULD return a document with the following structure.

{
  "name": <string identifying relay>,
  "description": <string with detailed information>,
  "pubkey": <administrative contact pubkey>,
  "contact": <administrative alternate contact>,
  "supported_nips": <a list of NIP numbers supported by the relay>,
  "software": <string identifying relay software URL>,
  "version": <string version identifier>
}

Any field may be omitted, and clients MUST ignore any additional fields they do not understand. Relays MUST accept CORS requests by sending Access-Control-Allow-Origin, Access-Control-Allow-Headers, and Access-Control-Allow-Methods headers.

Field Descriptions

Name

A relay may select a name for use in client software. This is a string, and SHOULD be less than 30 characters to avoid client truncation.

Description

Detailed plain-text information about the relay may be contained in the description string. It is recommended that this contain no markup, formatting or line breaks for word wrapping, and simply use double newline characters to separate paragraphs. There are no limitations on length.

Pubkey

An administrative contact may be listed with a pubkey, in the same format as Nostr events (32-byte hex for a secp256k1 public key). If a contact is listed, this provides clients with a recommended address to send encrypted direct messages (See NIP-04) to a system administrator. Expected uses of this address are to report abuse or illegal content, file bug reports, or request other technical assistance.

Relay operators have no obligation to respond to direct messages.

Contact

An alternative contact may be listed under the contact field as well, with the same purpose as pubkey. Use of a Nostr public key and direct message SHOULD be preferred over this. Contents of this field SHOULD be a URI, using schemes such as mailto or https to provide users with a means of contact.

Supported NIPs

As the Nostr protocol evolves, some functionality may only be available by relays that implement a specific NIP. This field is an array of the integer identifiers of NIPs that are implemented in the relay. Examples would include 1, for "NIP-01" and 9, for "NIP-09". Client-side NIPs SHOULD NOT be advertised, and can be ignored by clients.

Software

The relay server implementation MAY be provided in the software attribute. If present, this MUST be a URL to the project's homepage.

Version

The relay MAY choose to publish its software version as a string attribute. The string format is defined by the relay implementation. It is recommended this be a version number or commit identifier.

Extra Fields

Server Limitations

These are limitations imposed by the relay on clients. Your client should expect that requests which exceed these practical limitations are rejected or fail immediately.

{
...
  "limitation": {
        "max_message_length": 16384,
        "max_subscriptions": 20,
        "max_filters": 100,
        "max_limit": 5000,
        "max_subid_length": 100,
        "min_prefix": 4,
        "max_event_tags": 100,
        "max_content_length": 8196,
        "min_pow_difficulty": 30,
        "auth_required": true,
        "payment_required": true,
  }
...
}

max_message_length: this is the maximum number of bytes for incoming JSON that the relay will attempt to decode and act upon. When you send large subscriptions, you will be limited by this value. It also effectively limits the maximum size of any event. Value is calculated from [ to ] and is after UTF-8 serialization (so some unicode characters will cost 2-3 bytes). It is equal to the maximum size of the WebSocket message frame.

max_subscriptions: total number of subscriptions that may be active on a single websocket connection to this relay. It's possible that authenticated clients with a (paid) relationship to the relay may have higher limits.

max_filters: maximum number of filter values in each subscription. Must be one or higher.

max_subid_length: maximum length of subscription id as a string.

min_prefix: for authors and ids filters which are to match against a hex prefix, you must provide at least this many hex digits in the prefix.

max_limit: the relay server will clamp each filter's limit value to this number. This means the client won't be able to get more than this number of events from a single subscription filter. This clamping is typically done silently by the relay, but with this number, you can know that there are additional results if you narrowed your filter's time range or other parameters.

max_event_tags: in any event, this is the maximum number of elements in the tags list.

max_content_length: maximum number of characters in the content field of any event. This is a count of unicode characters. After serializing into JSON it may be larger (in bytes), and is still subject to the max_message_length, if defined.

min_pow_difficulty: new events will require at least this difficulty of PoW, based on NIP-13, or they will be rejected by this server.

auth_required: this relay requires NIP-42 authentication to happen before a new connection may perform any other action. Even if set to False, authentication may be required for specific actions.

payment_required: this relay requires payment before a new connection may perform any action.

Event Retention

There may be a cost associated with storing data forever, so relays may wish to state retention times. The values stated here are defaults for unauthenticated users and visitors. Paid users would likely have other policies.

Retention times are given in seconds, with null indicating infinity. If zero is provided, this means the event will not be stored at all, and preferably an error will be provided when those are received.

{
...
  "retention": [
    { "kinds": [0, 1, [5, 7], [40, 49]], "time": 3600 },
    { "kinds": [[40000, 49999]], "time": 100 },
    { "kinds": [[30000, 39999]], "count": 1000 },
    { "time": 3600, "count": 10000 }
  ]
...
}

retention is a list of specifications: each will apply to either all kinds, or a subset of kinds. Ranges may be specified for the kind field as a tuple of inclusive start and end values. Events of indicated kind (or all) are then limited to a count and/or time period.

It is possible to effectively blacklist Nostr-based protocols that rely on a specific kind number, by giving a retention time of zero for those kind values. While that is unfortunate, it does allow clients to discover servers that will support their protocol quickly via a single HTTP fetch.

There is no need to specify retention times for ephemeral events as defined in NIP-16 since they are not retained.

Content Limitations

Some relays may be governed by the arbitrary laws of a nation state. This may limit what content can be stored in cleartext on those relays. All clients are encouraged to use encryption to work around this limitation.

It is not possible to describe the limitations of each country's laws and policies which themselves are typically vague and constantly shifting.

Therefore, this field allows the relay operator to indicate which countries' laws might end up being enforced on them, and then indirectly on their users' content.

Users should be able to avoid relays in countries they don't like, and/or select relays in more favourable zones. Exposing this flexibility is up to the client software.

{
...
  "relay_countries": [ "CA", "US" ],
...
}

relay_countries: a list of two-level ISO country codes (ISO 3166-1 alpha-2) whose laws and policies may affect this relay. EU may be used for European Union countries.

Remember that a relay may be hosted in a country which is not the country of the legal entities who own the relay, so it's very likely a number of countries are involved.

Community Preferences

For public text notes at least, a relay may try to foster a local community. This would encourage users to follow the global feed on that relay, in addition to their usual individual follows. To support this goal, relays MAY specify some of the following values.

{
...
  "language_tags": [ "en", "en-419" ],
  "tags": [ "sfw-only", "bitcoin-only", "anime" ],
  "posting_policy": "https://example.com/posting-policy.html",
...
}

language_tags is an ordered list of IETF language tags indicating the major languages spoken on the relay.

tags is a list of limitations on the topics to be discussed. For example sfw-only indicates that only "Safe For Work" content is encouraged on this relay. This relies on assumptions of what the "work" "community" feels "safe" talking about. In time, a common set of tags may emerge that allow users to find relays that suit their needs, and client software will be able to parse these tags easily. The bitcoin-only tag indicates that any altcoin, "crypto" or blockchain comments will be ridiculed without mercy.

posting_policy is a link to a human-readable page which specifies the community policies for the relay. In cases where sfw-only is True, it's important to link to a page which gets into the specifics of your posting policy.

The description field should be used to describe your community goals and values, in brief. The posting_policy is for additional detail and legal terms. Use the tags field to signify limitations on content, or topics to be discussed, which could be machine processed by appropriate client software.

Pay-To-Relay

Relays that require payments may want to expose their fee schedules.

{
...
  "payments_url": "https://my-relay/payments",
  "fees": {
    "admission": [{ "amount": 1000000, "unit": "msats" }],
    "subscription": [{ "amount": 5000000, "unit": "msats", "period": 2592000 }],
    "publication": [{ "kinds": [4], "amount": 100, "unit": "msats" }],
  },
...
}

NIP-12

Generic Tag Queries

draft optional author:scsibug author:fiatjaf

Relays may support subscriptions over arbitrary tags. NIP-01 requires relays to respond to queries for e and p tags. This NIP allows any single-letter tag present in an event to be queried.

The <filters> object described in NIP-01 is expanded to contain arbitrary keys with a # prefix. Any single-letter key in a filter beginning with # is a tag query, and MUST have a value of an array of strings. The filter condition matches if the event has a tag with the same name, and there is at least one tag value in common with the filter and event. The tag name is the letter without the #, and the tag value is the second element. Subsequent elements are ignored for the purposes of tag queries.

Example Subscription Filter

The following provides an example of a filter that matches events of kind 1 with an r tag set to either foo or bar.

{
  "kinds": [1],
  "#r": ["foo", "bar"]
}

Client Behavior

Clients SHOULD use the supported_nips field to learn if a relay supports generic tag queries. Clients MAY send generic tag queries to any relay, if they are prepared to filter out extraneous responses from relays that do not support this NIP.

Rationale

The decision to reserve only single-letter tags to be usable in queries allow applications to make use of tags for all sorts of metadata, as it is their main purpose, without worrying that they might be bloating relay indexes. That also makes relays more lightweight, of course. And if some application or user is abusing single-letter tags with the intention of bloating relays that becomes easier to detect as single-letter tags will hardly be confused with some actually meaningful metadata some application really wanted to attach to the event with no spammy intentions.

Suggested Use Cases

Motivating examples for generic tag queries are provided below. This NIP does not promote or standardize the use of any specific tag for any purpose.

Decentralized Commenting System: clients can comment on arbitrary web pages, and easily search for other comments, by using a r ("reference", in this case an URL) tag and value.

Location-specific Posts: clients can use a g ("geohash") tag to associate a post with a physical location. Clients can search for a set of geohashes of varying precisions near them to find local content.

Hashtags: clients can use simple t ("hashtag") tags to associate an event with an easily searchable topic name. Since Nostr events themselves are not searchable through the protocol, this provides a mechanism for user-driven search.

NIP-13

Proof of Work

draft optional author:jb55 author:cameri

This NIP defines a way to generate and interpret Proof of Work for nostr notes. Proof of Work (PoW) is a way to add a proof of computational work to a note. This is a bearer proof that all relays and clients can universally validate with a small amount of code. This proof can be used as a means of spam deterrence.

difficulty is defined to be the number of leading zero bits in the NIP-01 id. For example, an id of 000000000e9d97a1ab09fc381030b346cdd7a142ad57e6df0b46dc9bef6c7e2d has a difficulty of 36 with 36 leading 0 bits.

002f... is 0000 0000 0010 1111... in binary, which has 10 leading zeroes. Do not forget to count leading zeroes for hex digits <= 7.

Mining

To generate PoW for a NIP-01 note, a nonce tag is used:

{"content": "It's just me mining my own business", "tags": [["nonce", "1", "21"]]}

When mining, the second entry to the nonce tag is updated, and then the id is recalculated (see NIP-01). If the id has the desired number of leading zero bits, the note has been mined. It is recommended to update the created_at as well during this process.

The third entry to the nonce tag SHOULD contain the target difficulty. This allows clients to protect against situations where bulk spammers targeting a lower difficulty get lucky and match a higher difficulty. For example, if you require 40 bits to reply to your thread and see a committed target of 30, you can safely reject it even if the note has 40 bits difficulty. Without a committed target difficulty you could not reject it. Committing to a target difficulty is something all honest miners should be ok with, and clients MAY reject a note matching a target difficulty if it is missing a difficulty commitment.

Example mined note

{
  "id": "000006d8c378af1779d2feebc7603a125d99eca0ccf1085959b307f64e5dd358",
  "pubkey": "a48380f4cfcc1ad5378294fcac36439770f9c878dd880ffa94bb74ea54a6f243",
  "created_at": 1651794653,
  "kind": 1,
  "tags": [
    [
      "nonce",
      "776797",
      "21"
    ]
  ],
  "content": "It's just me mining my own business",
  "sig": "284622fc0a3f4f1303455d5175f7ba962a3300d136085b9566801bc2e0699de0c7e31e44c81fb40ad9049173742e904713c3594a1da0fc5d2382a25c11aba977"
}

Validating

Here is some reference C code for calculating the difficulty (aka number of leading zero bits) in a nostr event id:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>int countLeadingZeroes(const char *hex) {
    int count = 0;

    for (int i = 0; i < strlen(hex); i++) {
        int nibble = (int)strtol((char[]){hex[i], '\0'}, NULL, 16);
        if (nibble == 0) {
            count += 4;
        } else {
            count += __builtin_clz(nibble) - 28;
            break;
        }
    }

    return count;
}

int main(int argc, char *argv[]) {
    if (argc != 2) {
        fprintf(stderr, "Usage: %s <hex_string>\n", argv[0]);
        return 1;
    }

    const char *hex_string = argv[1];
    int result = countLeadingZeroes(hex_string);
    printf("Leading zeroes in hex string %s: %d\n", hex_string, result);

    return 0;
}

Here is some JavaScript code for doing the same thing:

// hex should be a hexadecimal string (with no 0x prefix)
function countLeadingZeroes(hex) {
  let count = 0;

  for (let i = 0; i < hex.length; i++) {
    const nibble = parseInt(hex[i], 16);
    if (nibble === 0) {
      count += 4;
    } else {
      count += Math.clz32(nibble) - 28;
      break;
    }
  }

  return count;
}

Querying relays for PoW notes

Since relays allow searching on prefixes, you can use this as a way to filter notes of a certain difficulty:

$ echo '["REQ", "subid", {"ids": ["000000000"]}]'  | websocat wss://some-relay.com | jq -c '.[2]'
{"id":"000000000121637feeb68a06c8fa7abd25774bdedfa9b6ef648386fb3b70c387", ...}

Delegated Proof of Work

Since the NIP-01 note id does not commit to any signature, PoW can be outsourced to PoW providers, perhaps for a fee. This provides a way for clients to get their messages out to PoW-restricted relays without having to do any work themselves, which is useful for energy-constrained devices like mobile phones.

NIP-14

Subject tag in Text events.

draft optional author:unclebobmartin

This NIP defines the use of the "subject" tag in text (kind: 1) events.

(implemented in more-speech)

["subject": <string>]

Browsers often display threaded lists of messages. The contents of the subject tag can be used in such lists, instead of the more ad hoc approach of using the first few words of the message. This is very similar to the way email browsers display lists of incoming emails by subject rather than by contents.

When replying to a message with a subject, clients SHOULD replicate the subject tag. Clients MAY adorn the subject to denote that it is a reply. e.g. by prepending "Re:".

Subjects should generally be shorter than 80 chars. Long subjects will likely be trimmed by clients.

NIP-15

Nostr Marketplace (for resilient marketplaces)

draft optional author:fiatjaf author:benarc author:motorina0 author:talvasconcelos

Based on https://github.com/lnbits/Diagon-Alley

Implemented here https://github.com/lnbits/nostrmarket

Terms

merchant - seller of products with NOSTR key-pair

customer - buyer of products with NOSTR key-pair

product - item for sale by the merchant

stall - list of products controlled by merchant (a merchant can have multiple stalls)

marketplace - clientside software for searching stalls and purchasing products

Nostr Marketplace Clients

Merchant admin

Where the merchant creates, updates and deletes stalls and products, as well as where they manage sales, payments and communication with customers.

The merchant admin software can be purely clientside, but for convenience and uptime, implementations will likely have a server client listening for NOSTR events.

Marketplace

Marketplace software should be entirely clientside, either as a stand-alone app, or as a purely frontend webpage. A customer subscribes to different merchant NOSTR public keys, and those merchants stalls and products become listed and searchable. The marketplace client is like any other ecommerce site, with basket and checkout. Marketplaces may also wish to include a customer support area for direct message communication with merchants.

`Merchant` publishing/updating products (event)

A merchant can publish these events:

Kind	ㅤ	Description	NIP
`0`	`set_meta`	The merchant description (similar with any `nostr` public key).	NIP01
`30017`	`set_stall`	Create or update a stall.	NIP33 (Parameterized Replaceable Event)
`30018`	`set_product`	Create or update a product.	NIP33 (Parameterized Replaceable Event)
`4`	`direct_message`	Communicate with the customer. The messages can be plain-text or JSON.	NIP09
`5`	`delete`	Delete a product or a stall.	NIP05

Event `30017`: Create or update a stall.

Event Content:

{
    "id": <String, UUID generated by the merchant. Sequential IDs (`0`, `1`, `2`...) are discouraged>,
    "name": <String, stall name>,
    "description": <String (optional), stall description>,
    "currency": <String, currency used>,
    "shipping": [
        {
            "id": <String, UUID of the shipping zone, generated by the merchant>,
            "name": <String (optional), zone name>,
            "cost": <float, cost for shipping. The currency is defined at the stall level>,
            "countries": [<String, countries included in this zone>],
        }
    ]
}

Fields that are not self-explanatory:

shipping:

an array with possible shipping zones for this stall. The customer MUST choose exactly one shipping zone.
shipping to different zones can have different costs. For some goods (digital for example) the cost can be zero.
the id is an internal value used by the merchant. This value must be sent back as the customer selection.

Event Tags:

"tags": [["d", <String, id of stall]]

the d tag is required by NIP33. Its value MUST be the same as the stall id.

Event `30018`: Create or update a product

Event Content:

{
    "id": <String, UUID generated by the merchant.Sequential IDs (`0`, `1`, `2`...) are discouraged>,
    "stall_id": <String, UUID of the stall to which this product belong to>,
    "name": <String, product name>,
    "description": <String (optional), product description>,
    "images": <[String], array of image URLs, optional>,
    "currency": <String, currency used>,
    "price": <float, cost of product>,
    "quantity": <int, available items>,
    "specs": [
      [ <String, spec key>, <String, spec value>]
     ]
}

Fields that are not self-explanatory:

specs:

an array of key pair values. It allows for the Customer UI to present present product specifications in a structure mode. It also allows comparison between products
eg: [["operating_system", "Android 12.0"], ["screen_size", "6.4 inches"], ["connector_type", "USB Type C"]]

Open: better to move spec in the tags section of the event?

Event Tags:

  "tags": [
       ["d", <String, id of product],
       ["t", <String (optional), product category],
       ["t", <String (optional), product category],
       ...
    ]

the d tag is required by NIP33. Its value MUST be the same as the product id.

the t tag is as searchable tag (NIP12). It represents different categories that the product can be part of (food, fruits). Multiple t tags can be present.

Checkout events

All checkout events are sent as JSON strings using (NIP04).

The merchant and the customer can exchange JSON messages that represent different actions. Each JSON message MUST have a type field indicating the what the JSON represents. Possible types:

Message Type	Sent By	Description
0	Customer	New Order
1	Merchant	Payment Request
2	Merchant	Order Status Update

Step 1: `customer` order (event)

The below json goes in content of NIP04.

{
    "id": <String, UUID generated by the customer>,
    "type": 0,
    "name": <String (optional), ???>,
    "address": <String (optional), for physical goods an address should be provided>
    "message": "<String (optional), message for merchant>,
    "contact": {
        "nostr": <32-bytes hex of a pubkey>,
        "phone": <String (optional), if the customer wants to be contacted by phone>,
        "email": <String (optional), if the customer wants to be contacted by email>,
    },
    "items": [
        {
            "product_id": <String, UUID of the product>,
            "quantity": <int, how many products the customer is ordering>
        }
    ],
    "shipping_id": <String, UUID of the shipping zone>
}

Open: is contact.nostr required?

Step 2: `merchant` request payment (event)

Sent back from the merchant for payment. Any payment option is valid that the merchant can check.

The below json goes in content of NIP04.

payment_options/type include:

url URL to a payment page, stripe, paypal, btcpayserver, etc

btc onchain bitcoin address

ln bitcoin lightning invoice

lnurl bitcoin lnurl-pay

{
    "id": <String, UUID of the order>,
    "type": 1,
    "message": <String, message to customer, optional>,
    "payment_options": [
        {
            "type": <String, option type>,
            "link": <String, url, btc address, ln invoice, etc>
        },
        {
            "type": <String, option type>,
            "link": <String, url, btc address, ln invoice, etc>
        },
                {
            "type": <String, option type>,
            "link": <String, url, btc address, ln invoice, etc>
        }
    ]
}

Step 3: `merchant` verify payment/shipped (event)

Once payment has been received and processed.

The below json goes in content of NIP04.

{
    "id": <String, UUID of the order>,
    "type": 2,
    "message": <String, message to customer>,
    "paid": <Bool, true/false has received payment>,
    "shipped": <Bool, true/false has been shipped>,
}

Customer support events

Customer support is handled over whatever communication method was specified. If communicating via nostr, NIP-04 is used https://github.com/nostr-protocol/nips/blob/master/04.md.

Additional

Standard data models can be found here here

NIP-16

Event Treatment

draft optional author:Semisol

Relays may decide to allow replaceable and/or ephemeral events.

Regular Events

A regular event is defined as an event with a kind 1000 <= n < 10000. Upon a regular event being received, the relay SHOULD send it to all clients with a matching filter, and SHOULD store it. New events of the same kind do not affect previous events in any way.

Replaceable Events

A replaceable event is defined as an event with a kind 10000 <= n < 20000. Upon a replaceable event with a newer timestamp than the currently known latest replaceable event with the same kind and author being received, the old event SHOULD be discarded, effectively replacing what gets returned when querying for author:kind tuples.

Ephemeral Events

An ephemeral event is defined as an event with a kind 20000 <= n < 30000. Upon an ephemeral event being received, the relay SHOULD send it to all clients with a matching filter, and MUST NOT store it.

Client Behavior

Clients SHOULD use the supported_nips field to learn if a relay supports this NIP. Clients SHOULD NOT send ephemeral events to relays that do not support this NIP; they will most likely be persisted. Clients MAY send replaceable events to relays that may not support this NIP, and clients querying SHOULD be prepared for the relay to send multiple events and should use the latest one.

Suggested Use Cases

States: An application may create a state event that is replaced every time a new state is set (such as statuses)

Typing indicators: A chat application may use ephemeral events as a typing indicator.

Messaging: Two pubkeys can message over nostr using ephemeral events.

NIP-18

Reposts

draft optional author:jb55 author:fiatjaf author:arthurfranca

A repost is a kind 6 note that is used to signal to followers that another event is worth reading.

The content of a repost event is empty. Optionally, it MAY contain the stringified JSON of the reposted note event for quick look up.

The repost event MUST include an e tag with the id of the note that is being reposted. That tag MUST include a relay URL as its third entry to indicate where it can be fetched.

The repost SHOULD include a p tag with the pubkey of the event being reposted.

Quote Reposts

Quote reposts are kind 1 events with an embedded e tag (see NIP-08 and NIP-27). Because a quote repost includes an e tag, it may show up along replies to the reposted note.

NIP-19

bech32-encoded entities

draft optional author:jb55 author:fiatjaf author:Semisol

This NIP standardizes bech32-formatted strings that can be used to display keys, ids and other information in clients. These formats are not meant to be used anywhere in the core protocol, they are only meant for displaying to users, copy-pasting, sharing, rendering QR codes and inputting data.

It is recommended that ids and keys are stored in either hex or binary format, since these formats are closer to what must actually be used the core protocol.

Bare keys and ids

To prevent confusion and mixing between private keys, public keys and event ids, which are all 32 byte strings. bech32-(not-m) encoding with different prefixes can be used for each of these entities.

These are the possible bech32 prefixes:

npub: public keys

nsec: private keys

note: note ids

Example: the hex public key 3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d translates to npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6.

The bech32 encodings of keys and ids are not meant to be used inside the standard NIP-01 event formats or inside the filters, they're meant for human-friendlier display and input only. Clients should still accept keys in both hex and npub format for now, and convert internally.

Shareable identifiers with extra metadata

When sharing a profile or an event, an app may decide to include relay information and other metadata such that other apps can locate and display these entities more easily.

For these events, the contents are a binary-encoded list of TLV (type-length-value), with T and L being 1 byte each (uint8, i.e. a number in the range of 0-255), and V being a sequence of bytes of the size indicated by L.

These are the possible bech32 prefixes with TLV:

nprofile: a nostr profile

nevent: a nostr event

nrelay: a nostr relay

naddr: a nostr parameterized replaceable event coordinate (NIP-33)

These possible standardized TLV types are indicated here:

0: special

depends on the bech32 prefix:

for nprofile it will be the 32 bytes of the profile public key
for nevent it will be the 32 bytes of the event id
for nrelay, this is the relay URL
for naddr, it is the identifier (the "d" tag) of the event being referenced

1: relay

for nprofile, nevent and naddr, optionally, a relay in which the entity (profile or event) is more likely to be found, encoded as ascii
this may be included multiple times

2: author

for naddr, the 32 bytes of the pubkey of the event
for nevent, optionally, the 32 bytes of the pubkey of the event

3: kind

for naddr, the 32-bit unsigned integer of the kind, big-endian
for nevent, optionally, the 32-bit unsigned integer of the kind, big-endian

Examples

npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg should decode into the public key hex 7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e and vice-versa

nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5 should decode into the private key hex 67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa and vice-versa

nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gpp4mhxue69uhhytnc9e3k7mgpz4mhxue69uhkg6nzv9ejuumpv34kytnrdaksjlyr9p should decode into a profile with the following TLV items:

pubkey: 3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d
relay: wss://r.x.com
relay: wss://djbas.sadkb.com

Notes

npub keys MUST NOT be used in NIP-01 events or in NIP-05 JSON responses, only the hex format is supported there.

When decoding a bech32-formatted string, TLVs that are not recognized or supported should be ignored, rather than causing an error.

NIP-20

Command Results

draft optional author:jb55

When submitting events to relays, clients currently have no way to know if an event was successfully committed to the database. This NIP introduces the concept of command results which are like NOTICE's except provide more information about if an event was accepted or rejected.

A command result is a JSON object with the following structure that is returned when an event is successfully saved to the database or rejected:

["OK", <event_id>, <true|false>, <message>]

Relays MUST return true when the event is a duplicate and has already been saved. The message SHOULD start with duplicate: in this case.

Relays MUST return false when the event was rejected and not saved.

The message SHOULD provide additional information as to why the command succeeded or failed.

The message SHOULD start with blocked: if the pubkey or network address has been blocked, banned, or is not on a whitelist.

The message SHOULD start with invalid: if the event is invalid or doesn't meet some specific criteria (created_at is too far off, id is wrong, signature is wrong, etc)

The message SHOULD start with pow: if the event doesn't meet some proof-of-work difficulty. The client MAY consult the relay metadata at this point to retrieve the required posting difficulty.

The message SHOULD start with rate-limited: if the event was rejected due to rate limiting techniques.

The message SHOULD start with error: if the event failed to save due to a server issue.

Ephemeral events are not acknowledged with OK responses, unless there is a failure.

If the event or EVENT command is malformed and could not be parsed, a NOTICE message SHOULD be used instead of a command result. This NIP only applies to non-malformed EVENT commands.

Examples

Event successfully written to the database:

["OK", "b1a649ebe8b435ec71d3784793f3bbf4b93e64e17568a741aecd4c7ddeafce30", true, ""]

Event successfully written to the database because of a reason:

["OK", "b1a649ebe8b435ec71d3784793f3bbf4b93e64e17568a741aecd4c7ddeafce30", true, "pow: difficulty 25>=24"]

Event blocked due to ip filter

["OK", "b1a649ebe8...", false, "blocked: tor exit nodes not allowed"]

Event blocked due to pubkey ban

["OK", "b1a649ebe8...", false, "blocked: you are banned from posting here"]

Event blocked, pubkey not registered

["OK", "b1a649ebe8...", false, "blocked: please register your pubkey at https://my-expensive-relay.example.com"]

Event rejected, rate limited

["OK", "b1a649ebe8...", false, "rate-limited: slow down there chief"]

Event rejected, created_at too far off

["OK", "b1a649ebe8...", false, "invalid: event creation date is too far off from the current time. Is your system clock in sync?"]

Event rejected, insufficient proof-of-work difficulty

["OK", "b1a649ebe8...", false, "pow: difficulty 26 is less than 30"]

Event failed to save,

["OK", "b1a649ebe8...", false, "error: could not connect to the database"]

Client Handling

messages are meant for humans, with reason: prefixes so that clients can be slightly more intelligent with what to do with them. For example, with a rate-limited: reason the client may not show anything and simply try again with a longer timeout.

For the pow: prefix it may query relay metadata to get the updated difficulty requirement and try again in the background.

For the invalid: and blocked: prefix the client may wish to show these as styled error popups.

The prefixes include a colon so that the message can be cleanly separated from the prefix by taking everything after : and trimming it.

Future Extensions

This proposal SHOULD be extended to support further commands in the future, such as REQ and AUTH. They are left out of this initial version to keep things simpler.

NIP-21

`nostr:` URL scheme

draft optional author:fiatjaf

This NIP standardizes the usage of a common URL scheme for maximum interoperability and openness in the network.

The scheme is nostr:.

The identifiers that come after are expected to be the same as those defined in NIP-19 (except nsec).

Examples

nostr:npub1sn0wdenkukak0d9dfczzeacvhkrgz92ak56egt7vdgzn8pv2wfqqhrjdv9

nostr:nprofile1qqsrhuxx8l9ex335q7he0f09aej04zpazpl0ne2cgukyawd24mayt8gpp4mhxue69uhhytnc9e3k7mgpz4mhxue69uhkg6nzv9ejuumpv34kytnrdaksjlyr9p

nostr:note1fntxtkcy9pjwucqwa9mddn7v03wwwsu9j330jj350nvhpky2tuaspk6nqc

nostr:nevent1qqstna2yrezu5wghjvswqqculvvwxsrcvu7uc0f78gan4xqhvz49d9spr3mhxue69uhkummnw3ez6un9d3shjtn4de6x2argwghx6egpr4mhxue69uhkummnw3ez6ur4vgh8wetvd3hhyer9wghxuet5nxnepm

NIP-22

Event `created_at` Limits

draft optional author:jeffthibault author:Giszmo

Relays may define both upper and lower limits within which they will consider an event's created_at to be acceptable. Both the upper and lower limits MUST be unix timestamps in seconds as defined in NIP-01.

If a relay supports this NIP, the relay SHOULD send the client a NIP-20 command result saying the event was not stored for the created_at timestamp not being within the permitted limits.

Client Behavior

Clients SHOULD use the NIP-11 supported_nips field to learn if a relay uses event created_at time limits as defined by this NIP.

Motivation

This NIP formalizes restrictions on event timestamps as accepted by a relay and allows clients to be aware of relays that have these restrictions.

The event created_at field is just a unix timestamp and can be set to a time in the past or future. Relays accept and share events dated to 20 years ago or 50,000 years in the future. This NIP aims to define a way for relays that do not want to store events with any timestamp to set their own restrictions.

Replaceable events can behave rather unexpectedly if the user wrote them - or tried to write them - with a wrong system clock. Persisting an update with a backdated system now would result in the update not getting persisted without a notification and if they did the last update with a forward dated system, they will again fail to do another update with the now correct time.

A wide adoption of this NIP could create a better user experience as it would decrease the amount of events that appear wildly out of order or even from impossible dates in the distant past or future.

Keep in mind that there is a use case where a user migrates their old posts onto a new relay. If a relay rejects events that were not recently created, it cannot serve this use case.

Python (pseudocode) Example

import time

TIME = int(time.time())
LOWER_LIMIT = TIME - (60 * 60 * 24) # Define lower limit as 1 day into the past
UPPER_LIMIT = TIME + (60 * 15)      # Define upper limit as 15 minutes into the future

if event.created_at not in range(LOWER_LIMIT, UPPER_LIMIT):
  ws.send('["OK", event.id, False, "invalid: the event created_at field is out of the acceptable range (-24h, +15min) for this relay"]')

Note: These are just example limits, the relay operator can choose whatever limits they want.

NIP-23

Long-form Content

draft optional author:fiatjaf

This NIP defines kind:30023 (a parameterized replaceable event according to NIP-33) for long-form text content, generally referred to as "articles" or "blog posts".

"Social" clients that deal primarily with kind:1 notes should not be expected to implement this NIP.

Format

The .content of these events should be a string text in Markdown syntax.

Metadata

For the date of the last update the .created_at field should be used, for "tags"/"hashtags" (i.e. topics about which the event might be of relevance) the "t" event tag should be used, as per NIP-12.

Other metadata fields can be added as tags to the event as necessary. Here we standardize 4 that may be useful, although they remain strictly optional:

"title", for the article title

"image", for a URL pointing to an image to be shown along with the title

"summary", for the article summary

"published_at", for the timestamp in unix seconds (stringified) of the first time the article was published

Editability

These articles are meant to be editable, so they should make use of the replaceability feature of NIP-33 and include a "d" tag with an identifier for the article. Clients should take care to only publish and read these events from relays that implement that. If they don't do that they should also take care to hide old versions of the same article they may receive.

Linking

The article may be linked to using the NIP-19 naddr code along with the "a" tag (see NIP-33 and NIP-19).

References

References to other Nostr notes, articles or profiles must be made according to NIP-27, i.e. by using NIP-21 nostr:... links and optionally adding tags for these (see example below).

Example Event

{
  "kind": 30023,
  "created_at": 1675642635,
  "content": "Lorem [ipsum][nostr:nevent1qqst8cujky046negxgwwm5ynqwn53t8aqjr6afd8g59nfqwxpdhylpcpzamhxue69uhhyetvv9ujuetcv9khqmr99e3k7mg8arnc9] dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.\n\nRead more at nostr:naddr1qqzkjurnw4ksz9thwden5te0wfjkccte9ehx7um5wghx7un8qgs2d90kkcq3nk2jry62dyf50k0h36rhpdtd594my40w9pkal876jxgrqsqqqa28pccpzu.",
  "tags": [
    ["d", "lorem-ipsum"],
    ["title", "Lorem Ipsum"],
    ["published_at", "1296962229"],
    ["t", "placeholder"],
    ["e", "b3e392b11f5d4f28321cedd09303a748acfd0487aea5a7450b3481c60b6e4f87", "wss://relay.example.com"],
    ["a", "30023:a695f6b60119d9521934a691347d9f78e8770b56da16bb255ee286ddf9fda919:ipsum", "wss://relay.nostr.org"]
  ],
  "pubkey": "...",
  "id": "..."
}

NIP-25

Reactions

draft optional author:jb55

A reaction is a kind 7 note that is used to react to other notes.

The generic reaction, represented by the content set to a + string, SHOULD be interpreted as a "like" or "upvote".

A reaction with content set to - SHOULD be interpreted as a "dislike" or "downvote". It SHOULD NOT be counted as a "like", and MAY be displayed as a downvote or dislike on a post. A client MAY also choose to tally likes against dislikes in a reddit-like system of upvotes and downvotes, or display them as separate tallies.

The content MAY be an emoji, in this case it MAY be interpreted as a "like" or "dislike", or the client MAY display this emoji reaction on the post.

NIP: 26

Delegated Event Signing

draft optional author:markharding author:minds

This NIP defines how events can be delegated so that they can be signed by other keypairs.

Another application of this proposal is to abstract away the use of the 'root' keypairs when interacting with clients. For example, a user could generate new keypairs for each client they wish to use and authorize those keypairs to generate events on behalf of their root pubkey, where the root keypair is stored in cold storage.

Introducing the 'delegation' tag

This NIP introduces a new tag: delegation which is formatted as follows:

[
  "delegation",
  <pubkey of the delegator>,
  <conditions query string>,
  <delegation token: 64-byte Schnorr signature of the sha256 hash of the delegation string>
]

Delegation Token

The delegation token should be a 64-byte Schnorr signature of the sha256 hash of the following string:

nostr:delegation:<pubkey of publisher (delegatee)>:<conditions query string>

Conditions Query String

The following fields and operators are supported in the above query string:

Fields:

kind

Operators:

=${KIND_NUMBER} - delegatee may only sign events of this kind

created_at

Operators:

<${TIMESTAMP} - delegatee may only sign events created before the specified timestamp
>${TIMESTAMP} - delegatee may only sign events created after the specified timestamp

In order to create a single condition, you must use a supported field and operator. Multiple conditions can be used in a single query string, including on the same field. Conditions must be combined with &.

For example, the following condition strings are valid:

kind=1&created_at<1675721813

kind=0&kind=1&created_at>1675721813

kind=1&created_at>1674777689&created_at<1675721813

For the vast majority of use-cases, it is advisable that query strings should include a created_at after condition reflecting the current time, to prevent the delegatee from publishing historic notes on the delegator's behalf.

Example

# Delegator:
privkey: ee35e8bb71131c02c1d7e73231daa48e9953d329a4b701f7133c8f46dd21139c
pubkey:  8e0d3d3eb2881ec137a11debe736a9086715a8c8beeeda615780064d68bc25dd

# Delegatee:
privkey: 777e4f60b4aa87937e13acc84f7abcc3c93cc035cb4c1e9f7a9086dd78fffce1
pubkey:  477318cfb5427b9cfc66a9fa376150c1ddbc62115ae27cef72417eb959691396

Delegation string to grant note publishing authorization to the delegatee (477318cf) from now, for the next 30 days, given the current timestamp is 1674834236.

nostr:delegation:477318cfb5427b9cfc66a9fa376150c1ddbc62115ae27cef72417eb959691396:kind=1&created_at>1674834236&created_at<1677426236

The delegator (8e0d3d3e) then signs a SHA256 hash of the above delegation string, the result of which is the delegation token:

6f44d7fe4f1c09f3954640fb58bd12bae8bb8ff4120853c4693106c82e920e2b898f1f9ba9bd65449a987c39c0423426ab7b53910c0c6abfb41b30bc16e5f524

The delegatee (477318cf) can now construct an event on behalf of the delegator (8e0d3d3e). The delegatee then signs the event with its own private key and publishes.

{
  "id": "e93c6095c3db1c31d15ac771f8fc5fb672f6e52cd25505099f62cd055523224f",
  "pubkey": "477318cfb5427b9cfc66a9fa376150c1ddbc62115ae27cef72417eb959691396",
  "created_at": 1677426298,
  "kind": 1,
  "tags": [
    [
      "delegation",
      "8e0d3d3eb2881ec137a11debe736a9086715a8c8beeeda615780064d68bc25dd",
      "kind=1&created_at>1674834236&created_at<1677426236",
      "6f44d7fe4f1c09f3954640fb58bd12bae8bb8ff4120853c4693106c82e920e2b898f1f9ba9bd65449a987c39c0423426ab7b53910c0c6abfb41b30bc16e5f524"
    ]
  ],
  "content": "Hello, world!",
  "sig": "633db60e2e7082c13a47a6b19d663d45b2a2ebdeaf0b4c35ef83be2738030c54fc7fd56d139652937cdca875ee61b51904a1d0d0588a6acd6168d7be2909d693"
}

The event should be considered a valid delegation if the conditions are satisfied (kind=1, created_at>1674834236 and created_at<1677426236 in this example) and, upon validation of the delegation token, are found to be unchanged from the conditions in the original delegation string.

Clients should display the delegated note as if it was published directly by the delegator (8e0d3d3e).

Relay & Client Support

Relays should answer requests such as ["REQ", "", {"authors": ["A"]}] by querying both the pubkey and delegation tags [1] value.

Relays SHOULD allow the delegator (8e0d3d3e) to delete the events published by the delegatee (477318cf).

NIP-27

Text Note References

draft optional author:arthurfranca author:hodlbod author:fiatjaf

This document standardizes the treatment given by clients of inline references of other events and profiles inside the .content of any event that has readable text in its .content (such as kinds 1 and 30023).

When creating an event, clients should include mentions to other profiles and to other events in the middle of the .content using NIP-21 codes, such as nostr:nprofile1qqsw3dy8cpu...6x2argwghx6egsqstvg.

Including NIP-10-style tags (["e", <hex-id>, <relay-url>, <marker>]) for each reference is optional, clients should do it whenever they want the profile being mentioned to be notified of the mention, or when they want the referenced event to recognize their mention as a reply.

A reader client that receives an event with such nostr:... mentions in its .content can do any desired context augmentation (for example, linking to the profile or showing a preview of the mentioned event contents) it wants in the process. If turning such mentions into links, they could become internal links, NIP-21 links or direct links to web clients that will handle these references.

Example of a profile mention process

Suppose Bob is writing a note in a client that has search-and-autocomplete functionality for users that is triggered when they write the character @.

As Bob types "hello @mat" the client will prompt him to autocomplete with mattn's profile, showing a picture and name.

Bob presses "enter" and now he sees his typed note as "hello @mattn", @mattn is highlighted, indicating that it is a mention. Internally, however, the event looks like this:

{
  "content": "hello nostr:nprofile1qqszclxx9f5haga8sfjjrulaxncvkfekj097t6f3pu65f86rvg49ehqj6f9dh",
  "created_at": 1679790774,
  "id": "f39e9b451a73d62abc5016cffdd294b1a904e2f34536a208874fe5e22bbd47cf",
  "kind": 1,
  "pubkey": "79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798",
  "sig": "f8c8bab1b90cc3d2ae1ad999e6af8af449ad8bb4edf64807386493163e29162b5852a796a8f474d6b1001cddbaac0de4392838574f5366f03cc94cf5dfb43f4d",
  "tags": [
    [
      "p",
      "2c7cc62a697ea3a7826521f3fd34f0cb273693cbe5e9310f35449f43622a5cdc"
    ]
  ]
}

(Alternatively, the mention could have been a nostr:npub1... URL.)

After Bob publishes this event and Carol sees it, her client will initially display the .content as it is, but later it will parse the .content and see that there is a nostr: URL in there, decode it, extract the public key from it (and possibly relay hints), fetch that profile from its internal database or relays, then replace the full URL with the name @mattn, with a link to the internal page view for that profile.

Verbose and probably unnecessary considerations

The example above was very concrete, but it doesn't mean all clients have to implement the same flow. There could be clients that do not support autocomplete at all, so they just allow users to paste raw NIP-19 codes into the body of text, then prefix these with nostr: before publishing the event.

The flow for referencing other events is similar: a user could paste a note1... or nevent1... code and the client will turn that into a nostr:note1... or nostr:nevent1... URL. Then upon reading such references the client may show the referenced note in a preview box or something like that -- or nothing at all.

Other display procedures can be employed: for example, if a client that is designed for dealing with only kind:1 text notes sees, for example, a kind:30023 nostr:naddr1... URL reference in the .content, it can, for example, decide to turn that into a link to some hardcoded webapp capable of displaying such events.

Clients may give the user the option to include or not include tags for mentioned events or profiles. If someone wants to mention mattn without notifying them, but still have a nice augmentable/clickable link to their profile inside their note, they can instruct their client to not create a ["p", ...] tag for that specific mention.

In the same way, if someone wants to reference another note but their reference is not meant to show up along other replies to that same note, their client can choose to not include a corresponding ["e", ...] tag for any given nostr:nevent1... URL inside .content. Clients may decide to expose these advanced functionalities to users or be more opinionated about things.

NIP-28

Public Chat

draft optional author:ChristopherDavid author:fiatjaf author:jb55 author:Cameri

This NIP defines new event kinds for public chat channels, channel messages, and basic client-side moderation.

It reserves five event kinds (40-44) for immediate use:

40 - channel create

41 - channel metadata

42 - channel message

43 - hide message

44 - mute user

Client-centric moderation gives client developers discretion over what types of content they want included in their apps, while imposing no additional requirements on relays.

Kind 40: Create channel

Create a public chat channel.

In the channel creation content field, Client SHOULD include basic channel metadata (name, about, picture as specified in kind 41).

{
    "content": "{\"name\": \"Demo Channel\", \"about\": \"A test channel.\", \"picture\": \"https://placekitten.com/200/200\"}",
    ...
}

Kind 41: Set channel metadata

Update a channel's public metadata.

Clients and relays SHOULD handle kind 41 events similar to kind 0 metadata events.

Clients SHOULD ignore kind 41s from pubkeys other than the kind 40 pubkey.

Clients SHOULD support basic metadata fields:

name - string - Channel name

about - string - Channel description

picture - string - URL of channel picture

Clients MAY add additional metadata fields.

Clients SHOULD use NIP-10 marked "e" tags to recommend a relay.

{
    "content": "{\"name\": \"Updated Demo Channel\", \"about\": \"Updating a test channel.\", \"picture\": \"https://placekitten.com/201/201\"}",
    "tags": [["e", <channel_create_event_id>, <relay-url>]],
    ...
}

Kind 42: Create channel message

Send a text message to a channel.

Clients SHOULD use NIP-10 marked "e" tags to recommend a relay and specify whether it is a reply or root message.

Clients SHOULD append NIP-10 "p" tags to replies.

Root message:

{
    "content": <string>,
    "tags": [["e", <kind_40_event_id>, <relay-url>, "root"]],
    ...
}

Reply to another message:

{
    "content": <string>,
    "tags": [
        ["e", <kind_40_event_id>, <relay-url>, "root"],
        ["e", <kind_42_event_id>, <relay-url>, "reply"],
        ["p", <pubkey>, <relay-url>],
        ...
    ],
    ...
}

Kind 43: Hide message

User no longer wants to see a certain message.

The content may optionally include metadata such as a reason.

Clients SHOULD hide event 42s shown to a given user, if there is an event 43 from that user matching the event 42 id.

Clients MAY hide event 42s for other users other than the user who sent the event 43.

(For example, if three users 'hide' an event giving a reason that includes the word 'pornography', a Nostr client that is an iOS app may choose to hide that message for all iOS clients.)

{
    "content": "{\"reason\": \"Dick pic\"}",
    "tags": [["e", <kind_42_event_id>]],
    ...
}

Kind 44: Mute user

User no longer wants to see messages from another user.

The content may optionally include metadata such as a reason.

Clients SHOULD hide event 42s shown to a given user, if there is an event 44 from that user matching the event 42 pubkey.

Clients MAY hide event 42s for users other than the user who sent the event 44.

{
    "content": "{\"reason\": \"Posting dick pics\"}",
    "tags": [["p", <pubkey>]],
    ...
}

NIP-10 relay recommendations

For NIP-10 relay recommendations, clients generally SHOULD use the relay URL of the original (oldest) kind 40 event.

Clients MAY recommend any relay URL. For example, if a relay hosting the original kind 40 event for a channel goes offline, clients could instead fetch channel data from a backup relay, or a relay that clients trust more than the original relay.

Motivation

If we're solving censorship-resistant communication for social media, we may as well solve it also for Telegram-style messaging.

We can bring the global conversation out from walled gardens into a true public square open to all.

Additional info

Chat demo PR with fiatjaf+jb55 comments

Conversation about NIP16

NIP-33

Parameterized Replaceable Events

draft optional author:Semisol author:Kukks author:Cameri author:Giszmo

This NIP adds a new event range that allows for replacement of events that have the same d tag and kind unlike NIP-16 which only replaced by kind.

Implementation

The value of a tag is defined as the first parameter of a tag after the tag name.

A parameterized replaceable event is defined as an event with a kind 30000 <= n < 40000. Upon a parameterized replaceable event with a newer timestamp than the currently known latest replaceable event with the same kind, author and first d tag value being received, the old event SHOULD be discarded, effectively replacing what gets returned when querying for author:kind:d-tag tuples.

A missing or a d tag with no value should be interpreted equivalent to a d tag with the value as an empty string. Events from the same author with any of the following tags replace each other:

"tags":[["d",""]]

"tags":[]: implicit d tag with empty value

"tags":[["d"]]: implicit empty value ""

"tags":[["d",""],["d","not empty"]]: only first d tag is considered

"tags":[["d"],["d","some value"]]: only first d tag is considered

"tags":[["e"]]: same as no tags

"tags":[["d","","1"]]: only the first value is considered ("")

Clients SHOULD NOT use d tags with multiple values and SHOULD include the d tag even if it has no value to allow querying using the #d filter.

Referencing and tagging

Normally (as per NIP-01, NIP-12) the "p" tag is used for referencing public keys and the "e" tag for referencing event ids and the note, npub, nprofile or nevent are their equivalents for event tags (i.e. an nprofile is generally translated into a tag ["p", "<event hex id>", "<relay url>"]).

To support linking to parameterized replaceable events, the naddr code is introduced on NIP-19. It includes the public key of the event author and the d tag (and relays) such that the referenced combination of public key and d tag can be found.

The equivalent in tags to the naddr code is the tag "a", comprised of ["a", "<kind>:<pubkey>:<d-identifier>", "<relay url>"].

Client Behavior

Clients SHOULD use the supported_nips field to learn if a relay supports this NIP. Clients MAY send parameterized replaceable events to relays that may not support this NIP, and clients querying SHOULD be prepared for the relay to send multiple events and should use the latest one and are recommended to send a #d tag filter. Clients should account for the fact that missing d tags or ones with no value are not returned in tag filters, and are recommended to always include a d tag with a value.

NIP-36

Sensitive Content / Content Warning

draft optional author:fernandolguevara

The content-warning tag enables users to specify if the event's content needs to be approved by readers to be shown. Clients can hide the content until the user acts on it.

Spec

tag: content-warning
options:
 - [reason]: optional

Example

{
    "pubkey": "<pub-key>",
    "created_at": 1000000000,
    "kind": 1,
    "tags": [
      ["t", "hastag"],
      ["content-warning", "reason"] /* reason is optional */
    ],
    "content": "sensitive content with #hastag\n",
    "id": "<event-id>"
}

NIP-39

External Identities in Profiles

draft optional author:pseudozach author:Semisol

Abstract

Nostr protocol users may have other online identities such as usernames, profile pages, keypairs etc. they control and they may want to include this data in their profile metadata so clients can parse, validate and display this information.

`i` tag on a metadata event

A new optional i tag is introduced for kind 0 metadata event contents in addition to name, about, picture fields as included in NIP-01:

{
    "id": <id>,
    "pubkey": <pubkey>,
    ...
    "tags": [
        ["i", "github:semisol", "9721ce4ee4fceb91c9711ca2a6c9a5ab"],
        ["i", "twitter:semisol_public", "1619358434134196225"],
        ["i", "mastodon:bitcoinhackers.org/@semisol", "109775066355589974"]
        ["i", "telegram:1087295469", "nostrdirectory/770"]
    ]
}

An i tag will have two parameters, which are defined as the following:

platform:identity: This is the platform name (for example github) and the identity on that platform (for example semisol) joined together with :.

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>.

NIP-40

Expiration Timestamp

draft optional author:0xtlt

The expiration tag enables users to specify a unix timestamp at which the message SHOULD be considered expired (by relays and clients) and SHOULD be deleted by relays.

Spec

tag: expiration
values:
 - [UNIX timestamp in seconds]: required

Example

{
    "pubkey": "<pub-key>",
    "created_at": 1000000000,
    "kind": 1,
    "tags": [
      ["expiration", "1600000000"]
    ],
    "content": "This message will expire at the specified timestamp and be deleted by relays.\n",
    "id": "<event-id>"
}

Note: The timestamp should be in the same format as the created_at timestamp and should be interpreted as the time at which the message should be deleted by relays.

Client Behavior

Clients SHOULD use the supported_nips field to learn if a relay supports this NIP. Clients SHOULD NOT send expiration events to relays that do not support this NIP.

Clients SHOULD ignore events that have expired.

Relay Behavior

Relays MAY NOT delete expired messages immediately on expiration and MAY persist them indefinitely.

Relays SHOULD NOT send expired events to clients, even if they are stored.

Relays SHOULD drop any events that are published to them if they are expired.

An expiration timestamp does not affect storage of ephemeral events.

Suggested Use Cases

Temporary announcements - This tag can be used to make temporary announcements. For example, an event organizer could use this tag to post announcements about an upcoming event.

Limited-time offers - This tag can be used by businesses to make limited-time offers that expire after a certain amount of time. For example, a business could use this tag to make a special offer that is only available for a limited time.

Warning

The events could be downloaded by third parties as they are publicly accessible all the time on the relays. So don't consider expiring messages as a security feature for your conversations or other uses.

NIP-42

Authentication of clients to relays

draft optional author:Semisol author:fiatjaf

This NIP defines a way for clients to authenticate to relays by signing an ephemeral event.

Motivation

A relay may want to require clients to authenticate to access restricted resources. For example,

A relay may request payment or other forms of whitelisting to publish events -- this can naïvely be achieved by limiting publication to events signed by the whitelisted key, but with this NIP they may choose to accept any events as long as they are published from an authenticated user;

A relay may limit access to kind: 4 DMs to only the parties involved in the chat exchange, and for that it may require authentication before clients can query for that kind.

A relay may limit subscriptions of any kind to paying users or users whitelisted through any other means, and require authentication.

Definitions

This NIP defines a new message, AUTH, which relays can send when they support authentication and clients can send to relays when they want to authenticate. When sent by relays, the message is of the following form:

["AUTH", <challenge-string>]

And, when sent by clients, of the following form:

["AUTH", <signed-event-json>]

The signed event is an ephemeral event not meant to be published or queried, it must be of kind: 22242 and it should have at least two tags, one for the relay URL and one for the challenge string as received from the relay. Relays MUST exclude kind: 22242 events from being broadcasted to any client. created_at should be the current time. Example:

{
  "id": "...",
  "pubkey": "...",
  "created_at": 1669695536,
  "kind": 22242,
  "tags": [
    ["relay", "wss://relay.example.com/"],
    ["challenge", "challengestringhere"]
  ],
  "content": "",
  "sig": "..."
}

Protocol flow

At any moment the relay may send an AUTH message to the client containing a challenge. After receiving that the client may decide to authenticate itself or not. The challenge is expected to be valid for the duration of the connection or until a next challenge is sent by the relay.

The client may send an auth message right before performing an action for which it knows authentication will be required -- for example, right before requesting kind: 4 chat messages --, or it may do right on connection start or at some other moment it deems best. The authentication is expected to last for the duration of the WebSocket connection.

Upon receiving a message from an unauthenticated user it can't fulfill without authentication, a relay may choose to notify the client. For that it can use a NOTICE or OK message with a standard prefix "restricted: " that is readable both by humans and machines, for example:

["NOTICE", "restricted: we can't serve DMs to unauthenticated users, does your client implement NIP-42?"]

or it can return an OK message noting the reason an event was not written using the same prefix:

["OK", <event-id>, false, "restricted: we do not accept events from unauthenticated users, please sign up at https://example.com/"]

Signed Event Verification

To verify AUTH messages, relays must ensure:

that the kind is 22242;

that the event created_at is close (e.g. within ~10 minutes) of the current time;

that the "challenge" tag matches the challenge sent before;

that the "relay" tag matches the relay URL:

URL normalization techniques can be applied. For most cases just checking if the domain name is correct should be enough.

NIP-45

Event Counts

draft optional author:staab

Relays may support the COUNT verb, which provides a mechanism for obtaining event counts.

Motivation

Some queries a client may want to execute against connected relays are prohibitively expensive, for example, in order to retrieve follower counts for a given pubkey, a client must query all kind-3 events referring to a given pubkey and count them. The result may be cached, either by a client or by a separate indexing server as an alternative, but both options erode the decentralization of the network by creating a second-layer protocol on top of Nostr.

Filters and return values

This NIP defines a verb called COUNT, which accepts a subscription id and filters as specified in NIP 01.

["COUNT", <subscription_id>, <filters JSON>...]

Counts are returned using a COUNT response in the form {count: <integer>}. Relays may use probabilistic counts to reduce compute requirements.

["COUNT", <subscription_id>, {"count": <integer>}]

Examples:

# Followers count
["COUNT", <subscription_id>, {"kinds": [3], "#p": [<pubkey>]}]
["COUNT", <subscription_id>, {"count": 238}]

# Count posts and reactions
["COUNT", <subscription_id>, {"kinds": [1, 7], "authors": [<pubkey>]}]
["COUNT", <subscription_id>, {"count": 5}]

NIP-46

Nostr Connect

draft optional author:tiero author:giowe author:vforvalerio87

Rationale

Private keys should be exposed to as few systems - apps, operating systems, devices - as possible as each system adds to the attack surface.

Entering private keys can also be annoying and requires exposing them to even more systems such as the operating system's clipboard that might be monitored by malicious apps.

Terms

App: Nostr app on any platform that requires to act on behalf of a nostr account.

Signer: Nostr app that holds the private key of a nostr account and can sign on its behalf.

`TL;DR`

App and Signer sends ephemeral encrypted messages to each other using kind 24133, using a relay of choice.

App prompts the Signer to do things such as fetching the public key or signing events.

The content field must be an encrypted JSONRPC-ish request or response.

Signer Protocol

Messages

Request

{
  "id": <random_string>,
  "method": <one_of_the_methods>,
  "params": [<anything>, <else>]
}

Response

{
  "id": <request_id>,
  "result": <anything>,
  "error": <reason>
}

Methods

Mandatory

These are mandatory methods the remote signer app MUST implement:

describe

params []
result ["describe", "get_public_key", "sign_event", "connect", "disconnect", "delegate", ...]

get_public_key

params []
result pubkey

sign_event

params [event]
result event_with_signature

optional

connect

params [pubkey]

disconnect

params []

delegate

params [delegatee, { kind: number, since: number, until: number }]
result { from: string, to: string, cond: string, sig: string }

get_relays

params []
result { [url: string]: {read: boolean, write: boolean} }

nip04_encrypt

params [pubkey, plaintext]
result nip4 ciphertext

nip04_decrypt

params [pubkey, nip4 ciphertext]
result [plaintext]

NOTICE: pubkey and signature are hex-encoded strings.

Nostr Connect URI

Signer discovers App by scanning a QR code, clicking on a deep link or copy-pasting an URI.

The App generates a special URI with prefix nostrconnect:// and base path the hex-encoded pubkey with the following querystring parameters URL encoded

relay URL of the relay of choice where the App is connected and the Signer must send and listen for messages.

metadata metadata JSON of the App

name human-readable name of the App
url (optional) URL of the website requesting the connection
description (optional) description of the App
icons (optional) array of URLs for icons of the App.

JavaScript

const uri = `nostrconnect://<pubkey>?relay=${encodeURIComponent("wss://relay.damus.io")}&metadata=${encodeURIComponent(JSON.stringify({"name": "Example"}))}`

Example

nostrconnect://b889ff5b1513b641e2a139f661a661364979c5beee91842f8f0ef42ab558e9d4?relay=wss%3A%2F%2Frelay.damus.io&metadata=%7B%22name%22%3A%22Example%22%7D

Flows

The content field contains encrypted message as specified by NIP04. The kind chosen is 24133.

Connect

User clicks on "Connect" button on a website or scan it with a QR code

It will show an URI to open a "nostr connect" enabled Signer

In the URI there is a pubkey of the App ie. nostrconnect://<pubkey>&relay=<relay>&metadata=<metadata>

The Signer will send a message to ACK the connect request, along with his public key

Disconnect (from App)

User clicks on "Disconnect" button on the App

The App will send a message to the Signer with a disconnect request

The Signer will send a message to ACK the disconnect request

Disconnect (from Signer)

User clicks on "Disconnect" button on the Signer

The Signer will send a message to the App with a disconnect request

Get Public Key

The App will send a message to the Signer with a get_public_key request

The Signer will send back a message with the public key as a response to the get_public_key request

Sign Event

The App will send a message to the Signer with a sign_event request along with the event to be signed

The Signer will show a popup to the user to inspect the event and sign it

The Signer will send back a message with the event including the id and the schnorr signature as a response to the sign_event request

Delegate

The App will send a message with metadata to the Signer with a delegate request along with the conditions query string and the pubkey of the App to be delegated.

The Signer will show a popup to the user to delegate the App to sign on his behalf

The Signer will send back a message with the signed NIP-26 delegation token or reject it

NIP-50

Search Capability

draft optional author:brugeman author:mikedilger author:fiatjaf

Abstract

Many Nostr use cases require some form of general search feature, in addition to structured queries by tags or ids. Specifics of the search algorithms will differ between event kinds, this NIP only describes a general extensible framework for performing such queries.

A new search field is introduced for REQ messages from clients:

{
  ...
  "search": <string>
}

search field is a string describing a query in a human-readable form, i.e. "best nostr apps". Relays SHOULD interpret the query to the best of their ability and return events that match it. Relays SHOULD perform matching against content event field, and MAY perform matching against other fields if that makes sense in the context of a specific kind.

A query string may contain key:value pairs (two words separated by colon), these are extensions, relays SHOULD ignore extensions they don't support.

Clients may specify several search filters, i.e. ["REQ", "", { "search": "orange" }, { "kinds": [1, 2], "search": "purple" }]. Clients may include kinds, ids and other filter field to restrict the search results to particular event kinds.

Clients SHOULD use the supported_nips field to learn if a relay supports search filter. Clients MAY send search filter queries to any relay, if they are prepared to filter out extraneous responses from relays that do not support this NIP.

Clients SHOULD query several relays supporting this NIP to compensate for potentially different implementation details between relays.

Clients MAY verify that events returned by a relay match the specified query in a way that suits the client's use case, and MAY stop querying relays that have low precision.

Relays SHOULD exclude spam from search results by default if they supports some form of spam filtering.

Extensions

Relay MAY support these extensions:

include:spam - turn off spam filtering, if it was enabled by default

NIP-51

Lists

draft optional author:fiatjaf author:arcbtc author:monlovesmango author:eskema depends:33

A "list" event is defined as having a list of public and/or private tags. Public tags will be listed in the event tags. Private tags will be encrypted in the event content. Encryption for private tags will use NIP-04 - Encrypted Direct Message encryption, using the list author's private and public key for the shared secret. A distinct event kind should be used for each list type created.

If a list type should only be defined once per user (like the 'Mute' list), the list type's events should follow the specification for NIP-16 - Replaceable Events. These lists may be referred to as 'replaceable lists'.

Otherwise, the list type's events should follow the specification for NIP-33 - Parameterized Replaceable Events, where the list name will be used as the 'd' parameter. These lists may be referred to as 'parameterized replaceable lists'.

Replaceable List Event Example

Lets say a user wants to create a 'Mute' list and has keys:

priv: fb505c65d4df950f5d28c9e4d285ee12ffaf315deef1fc24e3c7cd1e7e35f2b1
pub: b1a5c93edcc8d586566fde53a20bdb50049a97b15483cb763854e57016e0fa3d

The user wants to publicly include these users:

["p", "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d"],
["p", "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245"]

and privately include these users (below is the JSON that would be encrypted and placed in the event content):

[
    ["p", "9ec7a778167afb1d30c4833de9322da0c08ba71a69e1911d5578d3144bb56437"],
    ["p", "8c0da4862130283ff9e67d889df264177a508974e2feb96de139804ea66d6168"]
]

Then the user would create a 'Mute' list event like below:

{
  "kind": 10000,
  "tags": [
    ["p", "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d"],
    ["p", "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245"],
  ],
  "content": "VezuSvWak++ASjFMRqBPWS3mK5pZ0vRLL325iuIL4S+r8n9z+DuMau5vMElz1tGC/UqCDmbzE2kwplafaFo/FnIZMdEj4pdxgptyBV1ifZpH3TEF6OMjEtqbYRRqnxgIXsuOSXaerWgpi0pm+raHQPseoELQI/SZ1cvtFqEUCXdXpa5AYaSd+quEuthAEw7V1jP+5TDRCEC8jiLosBVhCtaPpLcrm8HydMYJ2XB6Ixs=?iv=/rtV49RFm0XyFEwG62Eo9A==",
  ...other fields
}

Parameterized Replaceable List Event Example

Lets say a user wants to create a 'Categorized People' list of nostr people and has keys:

priv: fb505c65d4df950f5d28c9e4d285ee12ffaf315deef1fc24e3c7cd1e7e35f2b1
pub: b1a5c93edcc8d586566fde53a20bdb50049a97b15483cb763854e57016e0fa3d

The user wants to publicly include these users:

["p", "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d"],
["p", "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245"]

and privately include these users (below is the JSON that would be encrypted and placed in the event content):

[
    ["p", "9ec7a778167afb1d30c4833de9322da0c08ba71a69e1911d5578d3144bb56437"],
    ["p", "8c0da4862130283ff9e67d889df264177a508974e2feb96de139804ea66d6168"]
]

Then the user would create a 'Categorized People' list event like below:

{
  "kind": 30000,
  "tags": [
    ["d", "nostr"],
    ["p", "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d"],
    ["p", "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245"],
  ],
  "content": "VezuSvWak++ASjFMRqBPWS3mK5pZ0vRLL325iuIL4S+r8n9z+DuMau5vMElz1tGC/UqCDmbzE2kwplafaFo/FnIZMdEj4pdxgptyBV1ifZpH3TEF6OMjEtqbYRRqnxgIXsuOSXaerWgpi0pm+raHQPseoELQI/SZ1cvtFqEUCXdXpa5AYaSd+quEuthAEw7V1jP+5TDRCEC8jiLosBVhCtaPpLcrm8HydMYJ2XB6Ixs=?iv=/rtV49RFm0XyFEwG62Eo9A==",
  ...other fields
}

List Event Kinds

kind	list type
10000	Mute
10001	Pin
30000	Categorized People
30001	Categorized Bookmarks

Mute List

An event with kind 10000 is defined as a replaceable list event for listing content a user wants to mute. Any standardized tag can be included in a Mute List.

Pin List

An event with kind 10001 is defined as a replaceable list event for listing content a user wants to pin. Any standardized tag can be included in a Pin List.

Categorized People List

An event with kind 30000 is defined as a parameterized replaceable list event for categorizing people. The 'd' parameter for this event holds the category name of the list. The tags included in these lists MUST follow the format of kind 3 events as defined in NIP-02 - Contact List and Petnames.

Categorized Bookmarks List

An event with kind 30001 is defined as a parameterized replaceable list event for categorizing bookmarks. The 'd' parameter for this event holds the category name of the list. Any standardized tag can be included in a Categorized Bookmarks List.

NIP-56

Reporting

draft optional author:jb55

A report is a kind 1984 note that is used to report other notes for spam, illegal and explicit content.

The content MAY contain additional information submitted by the entity reporting the content.

Example events

{
  "kind": 1984,
  "tags": [
    [ "p", <pubkey>, "nudity"]
  ],
  "content": "",
  ...
}

{
  "kind": 1984,
  "tags": [
    [ "e", <eventId>, "illegal"],
    [ "p", <pubkey>]
  ],
  "content": "He's insulting the king!",
  ...
}

{
  "kind": 1984,
  "tags": [
    [ "p", <impersonator pubkey>, "impersonation"],
    [ "p", <victim pubkey>]
  ],
  "content": "Profile is imitating #[1]",
  ...
}

Client behavior

Clients can use reports from friends to make moderation decisions if they choose to. For instance, if 3+ of your friends report a profile as explicit, clients can have an option to automatically blur photos from said account.

Relay behavior

It is not recommended that relays perform automatic moderation using reports, as they can be easily gamed. Admins could use reports from trusted moderators to takedown illegal or explicit content if the relay does not allow such things.

NIP-57

Lightning Zaps

draft optional author:jb55 author:kieran

This NIP defines two new event types for recording lightning payments between users. 9734 is a zap request, representing a payer's request to a recipient's lightning wallet for an invoice. 9735 is a zap receipt, representing the confirmation by the recipient's lightning wallet that the invoice issued in response to a zap request has been paid.

Having lightning receipts on nostr allows clients to display lightning payments from entities on the network. These can be used for fun or for spam deterrence.

Protocol flow

Client calculates a recipient's lnurl pay request url from the zap tag on the event being zapped (see Appendix G), or by decoding their lud06 or lud16 field on their profile according to the lnurl specifications. The client MUST send a GET request to this url and parse the response. If allowsNostr exists and it is true, and if nostrPubkey exists and is a valid BIP 340 public key in hex, the client should associate this information with the user, along with the response's callback, minSendable, and maxSendable values.

Clients may choose to display a lightning zap button on each post or on a user's profile. If the user's lnurl pay request endpoint supports nostr, the client SHOULD use this NIP to request a zap receipt rather than a normal lnurl invoice.

When a user (the "sender") indicates they want to send a zap to another user (the "recipient"), the client should create a zap request event as described in Appendix A of this NIP and sign it.

Instead of publishing the zap request, the 9734 event should instead be sent to the callback url received from the lnurl pay endpoint for the recipient using a GET request. See Appendix B for details and an example.

The recipient's lnurl server will receive this request and validate it. See Appendix C for details on how to properly configure an lnurl server to support zaps, and Appendix D for details on how to validate the nostr query parameter.

If the request is valid, the server should fetch a description hash invoice where the description is this note and this note only. No additional lnurl metadata is included in the description. This will be returned in the response according to LUD06.

On receiving the invoice, the client MAY pay it or pass it to an app that can pay the invoice.

Once the invoice is paid, the recipient's lnurl server MUST generate a zap receipt as described in Appendix E, and publish it to the relays specified in the zap request.

Clients MAY fetch zap notes on posts and profiles, but MUST authorize their validity as described in Appendix F. If the zap request note contains a non-empty content, it may display a zap comment. Generally clients should show users the zap request note, and use the zap note to show "zap authorized by ..." but this is optional.

Reference and examples

Appendix A: Zap Request Event

A zap request is an event of kind 9734 that is not published to relays, but is instead sent to a recipient's lnurl pay callback url. This event's content MAY be an optional message to send along with the payment. The event MUST include the following tags:

relays is a list of relays the recipient's wallet should publish its zap receipt to. Note that relays should not be nested in an additional list, but should be included as shown in the example below.

amount is the amount in millisats the sender intends to pay, formatted as a string. This is recommended, but optional.

lnurl is the lnurl pay url of the recipient, encoded using bech32 with the prefix lnurl. This is recommended, but optional.

p is the hex-encoded pubkey of the recipient.

In addition, the event MAY include the following tags:

e is an optional hex-encoded event id. Clients MUST include this if zapping an event rather than a person.

a is an optional NIP-33 event coordinate that allows tipping parameterized replaceable events such as NIP-23 long-form notes.

Example:

{
  "kind": 9734,
  "content": "Zap!",
  "tags": [
    ["relays", "wss://nostr-pub.wellorder.com"],
    ["amount", "21000"],
    ["lnurl", "lnurl1dp68gurn8ghj7um5v93kketj9ehx2amn9uh8wetvdskkkmn0wahz7mrww4excup0dajx2mrv92x9xp"],
    ["p", "04c915daefee38317fa734444acee390a8269fe5810b2241e5e6dd343dfbecc9"],
    ["e", "9ae37aa68f48645127299e9453eb5d908a0cbb6058ff340d528ed4d37c8994fb"]
  ],
  "pubkey": "97c70a44366a6535c145b333f973ea86dfdc2d7a99da618c40c64705ad98e322",
  "created_at": 1679673265,
  "id": "30efed56a035b2549fcaeec0bf2c1595f9a9b3bb4b1a38abaf8ee9041c4b7d93",
  "sig": "f2cb581a84ed10e4dc84937bd98e27acac71ab057255f6aa8dfa561808c981fe8870f4a03c1e3666784d82a9c802d3704e174371aa13d63e2aeaf24ff5374d9d"
}

Appendix B: Zap Request HTTP Request

A signed zap request event is not published, but is instead sent using a HTTP GET request to the recipient's callback url, which was provided by the recipient's lnurl pay endpoint. This request should have the following query parameters defined:

amount is the amount in millisats the sender intends to pay

nostr is the 9734 zap request event, JSON encoded then URI encoded

lnurl is the lnurl pay url of the recipient, encoded using bech32 with the prefix lnurl

This request should return a JSON response with a pr key, which is the invoice the sender must pay to finalize his zap. Here is an example flow:

const senderPubkey // The sender's pubkey
const recipientPubkey = // The recipient's pubkey
const callback = // The callback received from the recipients lnurl pay endpoint
const lnurl = // The recipient's lightning address, encoded as a lnurl
const sats = 21

const amount = sats * 1000
const relays = ['wss://nostr-pub.wellorder.net']
const event = encodeURI(JSON.stringify(await signEvent({
  kind: [9734],
  content: "",
  pubkey: senderPubkey,
  created_at: Math.round(Date.now() / 1000),
  tags: [
    ["relays", ...relays],
    ["amount", amount.toString()],
    ["lnurl", lnurl],
    ["p", recipientPubkey],
  ],
})))

const {pr: invoice} = await fetchJson(`${callback}?amount=${amount}&nostr=${event}&lnurl=${lnurl}`)

Appendix C: LNURL Server Configuration

The lnurl server will need some additional pieces of information so that clients can know that zap invoices are supported:

Add a nostrPubkey to the lnurl-pay static endpoint /.well-known/lnurlp/<user>, where nostrPubkey is the nostr pubkey your server will use to sign zap receipt events. Clients will use this to validate zap receipts.

Add an allowsNostr field and set it to true.

Appendix D: LNURL Server Zap Request Validation

When a client sends a zap request event to a server's lnurl-pay callback URL, there will be a nostr query parameter where the contents of the event are URI- and JSON-encoded. If present, the zap request event must be validated in the following ways:

It MUST have a valid nostr signature

It MUST have tags

It MUST have only one p tag

It MUST have 0 or 1 e tags

There should be a relays tag with the relays to send the zap note to.

If there is an amount tag, it MUST be equal to the amount query parameter.

If there is an a tag, it MUST be a valid NIP-33 event coordinate

The event MUST then be stored for use later, when the invoice is paid.

Appendix E: Zap Receipt Event

A zap receipt is created by a lightning node when an invoice generated by a zap request is paid. Zap receipts are only created when the invoice description (committed to the description hash) contains a zap request note.

When receiving a payment, the following steps are executed:

Get the description for the invoice. This needs to be saved somewhere during the generation of the description hash invoice. It is saved automatically for you with CLN, which is the reference implementation used here.

Parse the bolt11 description as a JSON nostr event. This SHOULD be validated based on the requirements in Appendix D, either when it is received, or before the invoice is paid.

Create a nostr event of kind 9735 as described below, and publish it to the relays declared in the zap request.

The following should be true of the zap receipt event:

The content SHOULD be empty.

The created_at date SHOULD be set to the invoice paid_at date for idempotency.

tags MUST include the p tag AND optional e tag from the zap request.

The zap receipt MUST have a bolt11 tag containing the description hash bolt11 invoice.

The zap receipt MUST contain a description tag which is the JSON-encoded invoice description.

SHA256(description) MUST match the description hash in the bolt11 invoice.

The zap receipt MAY contain a preimage tag to match against the payment hash of the bolt11 invoice. This isn't really a payment proof, there is no real way to prove that the invoice is real or has been paid. You are trusting the author of the zap receipt for the legitimacy of the payment.

The zap receipt is not a proof of payment, all it proves is that some nostr user fetched an invoice. The existence of the zap receipt implies the invoice as paid, but it could be a lie given a rogue implementation.

A reference implementation for a zap-enabled lnurl server can be found here.

Example zap receipt:

{
    "id": "67b48a14fb66c60c8f9070bdeb37afdfcc3d08ad01989460448e4081eddda446",
    "pubkey": "9630f464cca6a5147aa8a35f0bcdd3ce485324e732fd39e09233b1d848238f31",
    "created_at": 1674164545,
    "kind": 9735,
    "tags": [
      ["p", "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245"],
      ["e", "3624762a1274dd9636e0c552b53086d70bc88c165bc4dc0f9e836a1eaf86c3b8"],
      ["bolt11", "lnbc10u1p3unwfusp5t9r3yymhpfqculx78u027lxspgxcr2n2987mx2j55nnfs95nxnzqpp5jmrh92pfld78spqs78v9euf2385t83uvpwk9ldrlvf6ch7tpascqhp5zvkrmemgth3tufcvflmzjzfvjt023nazlhljz2n9hattj4f8jq8qxqyjw5qcqpjrzjqtc4fc44feggv7065fqe5m4ytjarg3repr5j9el35xhmtfexc42yczarjuqqfzqqqqqqqqlgqqqqqqgq9q9qxpqysgq079nkq507a5tw7xgttmj4u990j7wfggtrasah5gd4ywfr2pjcn29383tphp4t48gquelz9z78p4cq7ml3nrrphw5w6eckhjwmhezhnqpy6gyf0"],
      ["description", "{\"pubkey\":\"32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245\",\"content\":\"\",\"id\":\"d9cc14d50fcb8c27539aacf776882942c1a11ea4472f8cdec1dea82fab66279d\",\"created_at\":1674164539,\"sig\":\"77127f636577e9029276be060332ea565deaf89ff215a494ccff16ae3f757065e2bc59b2e8c113dd407917a010b3abd36c8d7ad84c0e3ab7dab3a0b0caa9835d\",\"kind\":9734,\"tags\":[[\"e\",\"3624762a1274dd9636e0c552b53086d70bc88c165bc4dc0f9e836a1eaf86c3b8\"],[\"p\",\"32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245\"],[\"relays\",\"wss://relay.damus.io\",\"wss://nostr-relay.wlvs.space\",\"wss://nostr.fmt.wiz.biz\",\"wss://relay.nostr.bg\",\"wss://nostr.oxtr.dev\",\"wss://nostr.v0l.io\",\"wss://brb.io\",\"wss://nostr.bitcoiner.social\",\"ws://monad.jb55.com:8080\",\"wss://relay.snort.social\"]]}"],
      ["preimage", "5d006d2cf1e73c7148e7519a4c68adc81642ce0e25a432b2434c99f97344c15f"]
    ],
    "content": "",
    "sig": "b0a3c5c984ceb777ac455b2f659505df51585d5fd97a0ec1fdb5f3347d392080d4b420240434a3afd909207195dac1e2f7e3df26ba862a45afd8bfe101c2b1cc"
  }

Appendix F: Validating Zap Receipts

A client can retrieve zap receipts on events and pubkeys using a NIP-01 filter, for example {"kinds": [9735], "#e": [...]}. Zaps MUST be validated using the following steps:

The zap receipt event's pubkey MUST be the same as the recipient's lnurl provider's nostrPubkey (retrieved in step 1 of the protocol flow).

The invoiceAmount contained in the bolt11 tag of the zap receipt MUST equal the amount tag of the zap request (if present).

The lnurl tag of the zap request (if present) SHOULD equal the recipient's lnurl.

Appendix G: `zap` tag on zapped event

When an event includes a zap tag, clients SHOULD calculate the lnurl pay request based on it's value instead of the profile's field. An optional third argument on the tag specifies the type of value, either lud06 or lud16.

{
    "tags": [
        [ "zap", "[email protected]", "lud16" ]
    ]
}

Future Work

Zaps can be extended to be more private by encrypting zap request notes to the target user, but for simplicity it has been left out of this initial draft.

NIP-58

Badges

draft optional author:cameri

Three special events are used to define, award and display badges in user profiles:

A "Badge Definition" event is defined as a parameterized replaceable event with kind 30009 having a d tag with a value that uniquely identifies the badge (e.g. bravery) published by the badge issuer. Badge definitions can be updated.

A "Badge Award" event is a kind 8 event with a single a tag referencing a "Define Badge" event and one or more p tags, one for each pubkey the badge issuer wishes to award. The value for the a tag MUST follow the format defined in NIP-33. Awarded badges are immutable and non-transferrable.

A "Profile Badges" event is defined as a parameterized replaceable event with kind 30008 with a d tag with the value profile_badges. Profile badges contain an ordered list of pairs of a and e tags referencing a Badge Definition and a Badge Award for each badge to be displayed.

Badge Definition event

The following tags MUST be present:

d tag with the unique name of the badge.

The following tags MAY be present:

A name tag with a short name for the badge.

image tag whose value is the URL of a high-resolution image representing the badge. The second value optionally specifies the dimensions of the image as widthxheight in pixels. Badge recommended dimensions is 1024x1024 pixels.

A description tag whose value MAY contain a textual representation of the image, the meaning behind the badge, or the reason of it's issuance.

One or more thumb tags whose first value is an URL pointing to a thumbnail version of the image referenced in the image tag. The second value optionally specifies the dimensions of the thumbnail as widthxheight in pixels.

Badge Award event

The following tags MUST be present:

An a tag referencing a kind 30009 Badge Definition event.

One or more p tags referencing each pubkey awarded.

Profile Badges Event

The number of badges a pubkey can be awarded is unbounded. The Profile Badge event allows individual users to accept or reject awarded badges, as well as choose the display order of badges on their profiles.

The following tags MUST be present:

A d tag with the unique identifier profile_badges

The following tags MAY be present:

Zero or more ordered consecutive pairs of a and e tags referencing a kind 30009 Badge Definition and kind 8 Badge Award, respectively. Clients SHOULD ignore a without corresponding e tag and viceversa. Badge Awards referenced by the e tags should contain the same a tag.

Motivation

Users MAY be awarded badges (but not limited to) in recognition, in gratitude, for participation, or in appreciation of a certain goal, task or cause.

Users MAY choose to decorate their profiles with badges for fame, notoriety, recognition, support, etc., from badge issuers they deem reputable.

Recommendations

Badge issuers MAY include some Proof of Work as per NIP-13 when minting Badge Definitions or Badge Awards to embed them with a combined energy cost, arguably making them more special and valuable for users that wish to collect them.

Clients MAY whitelist badge issuers (pubkeys) for the purpose of ensuring they retain a valuable/special factor for their users.

Badge image recommended aspect ratio is 1:1 with a high-res size of 1024x1024 pixels.

Badge thumbnail image recommended dimensions are: 512x512 (xl), 256x256 (l), 64x64 (m), 32x32 (s) and 16x16 (xs).

Clients MAY choose to render less badges than those specified by users in the Profile Badges event or replace the badge image and thumbnails with ones that fits the theme of the client.

Clients SHOULD attempt to render the most appropriate badge thumbnail according to the number of badges chosen by the user and space available. Clients SHOULD attempt render the high-res version on user action (click, tap, hover).

Example of a Badge Definition event

{
  "pubkey": "alice",
  "kind": 30009,
  "tags": [
    ["d", "bravery"],
    ["name", "Medal of Bravery"],
    ["description", "Awarded to users demonstrating bravery"],
    ["image", "https://nostr.academy/awards/bravery.png", "1024x1024"],
    ["thumb", "https://nostr.academy/awards/bravery_256x256.png", "256x256"],
  ],
  ...
}

Example of Badge Award event

{
  "id": "<badge award event id>",
  "kind": 8,
  "pubkey": "alice",
  "tags": [
    ["a", "30009:alice:bravery"],
    ["p", "bob", "wss://relay"],
    ["p", "charlie", "wss://relay"],
  ],
  ...
}

Example of a Profile Badges event

Honorable Bob The Brave:

{
  "kind": 30008,
  "pubkey": "bob",
  "tags": [
    ["d", "profile_badges"],
    ["a", "30009:alice:bravery"],
    ["e", "<bravery badge award event id>", "wss://nostr.academy"],
    ["a", "30009:alice:honor"],
    ["e", "<honor badge award event id>", "wss://nostr.academy"],
  ],
  ...
}

NIP-65

Relay List Metadata

draft optional author:mikedilger

A special replaceable event meaning "Relay List Metadata" is defined as an event with kind 10002 having a list of r tags, one for each relay the author uses to either read or write to.

The primary purpose of this relay list is to advertise to others, not for configuring one's client.

The content is not used and SHOULD be an empty string.

The r tags can have a second parameter as either read or write. If it is omitted, it means the author uses the relay for both purposes.

Clients SHOULD, as with all replaceable events, use only the most recent kind-10002 event they can find.

The meaning of read and write

Write relays are for events that are intended for anybody (e.g. your followers). Read relays are for events that address a particular person.

Clients SHOULD write feed-related events created by their user to their user's write relays.

Clients SHOULD read feed-related events created by another from at least some of that other person's write relays. Explicitly, they SHOULD NOT expect them to be available at their user's read relays. It SHOULD NOT be presumed that the user's read relays coincide with the write relays of the people the user follows.

Clients SHOULD read events that tag their user from their user's read relays.

Clients SHOULD write events that tag a person to at least some of that person's read relays. Explicitly, they SHOULD NOT expect that person will pick them up from their user's write relays. It SHOULD NOT be presumed that the user's write relays coincide with the read relays of the person being tagged.

Clients SHOULD presume that if their user has a pubkey in their ContactList (kind 3) that it is because they wish to see that author's feed-related events. But clients MAY presume otherwise.

Motivation

There is a common nostr use case where users wish to follow the content produced by other users. This is evidenced by the implicit meaning of the Contact List in NIP-02

Because users don't often share the same sets of relays, ad-hoc solutions have arisen to get that content, but these solutions negatively impact scalability and decentralization:

Most people are sending their posts to the same most popular relays in order to be more widely seen

Many people are pulling from a large number of relays (including many duplicate events) in order to get more data

Events are being copied between relays, oftentimes to many different relays

Purposes

The purpose of this NIP is to help clients find the events of the people they follow, to help tagged events get to the people tagged, and to help nostr scale better.

Suggestions

It is suggested that people spread their kind 10002 events to many relays, but write their normal feed-related events to a much smaller number of relays (between 2 to 6 relays). It is suggested that clients offer a way for users to spread their kind 10002 events to many more relays than they normally post to.

Authors may post events outside of the feed that they wish their followers to follow by posting them to relays outside of those listed in their "Relay List Metadata". For example, an author may want to reply to someone without all of their followers watching.

It is suggested that relays allow any user to write their own kind 10002 event (optionally with AUTH to verify it is their own) even if they are not otherwise subscribed to the relay because

finding where someone posts is rather important

these events do not have content that needs management

relays only need to store one replaceable event per pubkey to offer this service

Why not in kind `0` Metadata

Even though this is user related metadata, it is a separate event from kind 0 in order to keep it small (as it should be widely spread) and to not have content that may require moderation by relay operators so that it is more acceptable to relays.

Example

{
  "kind": 10002,
  "tags": [
    ["r", "wss://alicerelay.example.com"],
    ["r", "wss://brando-relay.com"],
    ["r", "wss://expensive-relay.example2.com", "write"],
    ["r", "wss://nostr-relay.example.com", "read"],
  ],
  "content": "",
  ...other fields

NIP-78

Arbitrary custom app data

draft optional author:sandwich author:fiatjaf

The goal of this NIP is to enable remoteStorage-like capabilities for custom applications that do not care about interoperability.

Even though interoperability is great, some apps do not want or do not need interoperability, and it wouldn't make sense for them. Yet Nostr can still serve as a generalized data storage for these apps in a "bring your own database" way, for example: a user would open an app and somehow input their preferred relay for storage, which would then enable these apps to store application-specific data there.

Nostr event

This NIP specifies the use of event kind 30078 (parameterized replaceable event) with a d tag containing some reference to the app name and context -- or any other arbitrary string. content and other tags can be anything or in any format.

Some use cases

User personal settings on Nostr clients (and other apps unrelated to Nostr)

A way for client developers to propagate dynamic parameters to users without these having to update

Personal private data generated by apps that have nothing to do with Nostr, but allow users to use Nostr relays as their personal database

NIP-94

File Metadata

draft optional author:frbitten author:kieran author:lovvtide author:fiatjaf author:staab

The purpose of this NIP is to allow an organization and classification of shared files. So that relays can filter and organize in any way that is of interest. With that, multiple types of filesharing clients can be created. NIP-94 support is not expected to be implemented by "social" clients that deal with kind:1 notes or by longform clients that deal with kind:30023 articles.

Event format

This NIP specifies the use of the 1063 event type, having in content a description of the file content, and a list of tags described below:

url the url to download the file

m a string indicating the data type of the file. The MIME types format must be used (https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types)

"aes-256-gcm" (optional) key and nonce for AES-GCM encryption with tagSize always 128bits

x containing the SHA-256 hexencoded string of the file.

size (optional) size of file in bytes

dim (optional) size of file in pixels in the form <width>x<height>

magnet (optional) URI to magnet file

i (optional) torrent infohash

blurhash(optional) the blurhash to show while the file is being loaded by the client

{
  "id": <32-bytes lowercase hex-encoded sha256 of the the serialized event data>,
  "pubkey": <32-bytes lowercase hex-encoded public key of the event creator>,
  "created_at": <unix timestamp in seconds>,
  "kind": 1063,
  "tags": [
    ["url",<string with URI of file>],
    ["aes-256-gcm",<key>, <iv>],
    ["m", <MIME type>],
    ["x",<Hash SHA-256>],
    ["size", <size of file in bytes>],
    ["dim", <size of file in pixels>],
    ["magnet",<magnet URI> ],
    ["i",<torrent infohash>],
    ["blurhash", <value>]
  ],
  "content": <description>,
  "sig": <64-bytes hex of the signature of the sha256 hash of the serialized event data, which is the same as the "id" field>
}

Suggested use cases

A relay for indexing shared files. For example, to promote torrents.

A pinterest-like client where people can share their portfolio and inspire others.

A simple way to distribute configurations and software updates.