NIP-19 Identifier Routing

NIP-19 defines the bech32-encoded identifiers used throughout Nostr (npub1..., note1..., naddr1..., etc.). This project routes all of them through a single root-level page at /:nip19, implemented by src/pages/NIP19Page.tsx.

Use this skill when the user wants to populate the NIP19Page sections with real views, add a new identifier type, or build links that point into the Nostr routing system.

Identifier Reference

note1 vs nevent1

• note1 carries only an event ID, and is canonically tied to kind:1 text notes.
• nevent1 can reference any kind and can carry relay hints + author pubkey. Prefer nevent1 for non-kind-1 events or when you want to ship relay hints with a link.

npub1 vs nprofile1

• npub1 is just a pubkey.
• nprofile1 adds relay hints and a petname. Prefer it for shareable profile links where discoverability matters.

Routing Rules

1. All NIP-19 identifiers are handled at the URL root: /:nip19 in AppRouter.tsx. Never nest them under paths like /note/:id or /profile/:npub.
2. Invalid, vacant, or unsupported identifiers (including nsec1 and nrelay1) render the 404 page. The NIP19Page boilerplate already handles this.
3. Addressable event URLs must include the author. naddr1 already encodes pubkey + kind + identifier, which is exactly what a secure query filter needs. If you ever design an alternative URL, use the shape /:npub/:dtag, never /:dtag alone — otherwise anyone can publish a conflicting event with the same d tag.

Decoding and Filtering

Nostr relay filters only accept hex strings. Always decode the NIP-19 identifier before building a filter.

import { nip19 } from 'nostr-tools';

const decoded = nip19.decode(value); // throws on invalid input

switch (decoded.type) {
  case 'npub': {
    const pubkey = decoded.data; // hex string
    return nostr.query([{ kinds: [0], authors: [pubkey], limit: 1 }]);
  }

  case 'nprofile': {
    const { pubkey /*, relays */ } = decoded.data;
    return nostr.query([{ kinds: [0], authors: [pubkey], limit: 1 }]);
  }

  case 'note': {
    const id = decoded.data;
    return nostr.query([{ ids: [id], kinds: [1], limit: 1 }]);
  }

  case 'nevent': {
    const { id /*, relays, author, kind */ } = decoded.data;
    return nostr.query([{ ids: [id], limit: 1 }]);
  }

  case 'naddr': {
    const { kind, pubkey, identifier } = decoded.data;
    return nostr.query([{
      kinds: [kind],
      authors: [pubkey],        // critical: prevents d-tag spoofing
      '#d': [identifier],
      limit: 1,
    }]);
  }

  default:
    // nsec, nrelay, unknown → 404
    throw new Error('Unsupported Nostr identifier');
}

Common mistakes

// ❌ Passing bech32 into a filter
nostr.query([{ ids: [naddr] }]);

// ❌ Addressable lookup without the author — anyone can spoof the d-tag
nostr.query([{ kinds: [30023], '#d': [slug] }]);

// ✅ Decode first, then include author
const { kind, pubkey, identifier } = nip19.decode(naddr).data;
nostr.query([{ kinds: [kind], authors: [pubkey], '#d': [identifier] }]);

Populating NIP19Page

src/pages/NIP19Page.tsx already:

• Decodes params.nip19 with nip19.decode.
• Branches on decoded.type with a section for each supported identifier.
• Redirects invalid / unsupported identifiers to the 404 page.
• Provides a responsive container wrapper.

To turn it into a real router, replace each placeholder section with a concrete component:

Inside each branch, pass the decoded payload (not the raw bech32 string) to a child component. That keeps filter construction colocated with the fetching hook and removes any chance of a re-decode mismatch.

Linking to NIP-19 Routes

When building links elsewhere in the app:

import { nip19 } from 'nostr-tools';
import { Link } from 'react-router-dom';

// To a profile
<Link to={`/${nip19.npubEncode(pubkey)}`}>Profile</Link>

// To an addressable event (article, product, …)
<Link to={`/${nip19.naddrEncode({ kind, pubkey, identifier, relays })}`}>
  Open
</Link>

// To a specific event of any kind, with relay hints
<Link to={`/${nip19.neventEncode({ id, relays, author, kind })}`}>Open</Link>

Always encode with the most specific identifier you have context for (nprofile > npub, nevent > note, naddr for addressable). The extra metadata makes links more robust across relays.

Security Recap

• Decode before querying.
• For addressable events, always include authors: [pubkey] in the filter — the d tag alone is not a trust boundary.
• Treat nsec1 and any unknown/invalid identifier as 404. Never render, log, or echo a decoded nsec.