NIP-37 defines an encrypted storage event for unsigned draft events of any kind. A user composing a long-form article, an upcoming calendar event, or a message they may want to send later can store the draft on relays under a kind 31234 event, encrypted to their own key with NIP-44. The draft is recoverable from any client that holds the user’s key, and the same NIP defines a separate kind:10013 list event that names the relays the user wants their private drafts stored on.

How It Works

A draft wrap is a parameterised replaceable event of kind 31234. The unsigned draft event is JSON-stringified, NIP-44 encrypted to the signer’s own public key, and placed in .content. A k tag declares the kind of the draft so a client can group drafts by event type. A d tag carries the draft identifier so the wrap can be replaced as the draft evolves, and a NIP-40 expiration tag is recommended so old drafts age out automatically.

{
  "kind": 31234,
  "tags": [
    ["d", "<identifier>"],
    ["k", "<kind of the draft event>"],
    ["expiration", "<unix-timestamp>"]
  ],
  "content": "<nip44Encrypt(JSON.stringify(draft_event))>"
}

A blanked .content field signals the draft has been deleted.

Checkpoints

Kind 1234 defines checkpoints belonging to a parent kind:31234 event. Checkpoints carry an a tag pointing back at the parent draft and let a client store revision history alongside the latest draft.

{
  "kind": 1234,
  "tags": [
    ["a", "31234:<pubkey>:<identifier>"]
  ],
  "content": "<nip44Encrypt(JSON.stringify(draft_event))>"
}

Relay List for Private Content (kind 10013)

Kind 10013 is a replaceable event whose tags list the relays the user wants to store private content on, including draft wraps. Clients publishing kind 31234 SHOULD publish to relays listed on the user’s kind 10013 event. This separates the relay set used for public posting (NIP-65) from the relay set used for private content storage, so a user can pin private drafts to a small set of trusted relays without exposing that set in their public outbox.

Implementations

  • Notedeck - stores private-sync relays as a kind-10013 list (added 2026-06)

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