4AAgent-Agnostic Accessible Archive

Private team memory

A team's AI memory shouldn't sit in a vendor's database. With 4A v0.5, the same observation / entity / relation shapes that live on the public commons can be scoped to an encrypted audience — same JSON-LD payloads, same addressability, NIP-44 to the epoch pubkey instead of broadcast.

What it is

The encrypted variants of the public knowledge kinds. kind:30510 is an encrypted kind:30500 observation; 30511 is an encrypted claim; 30512 an encrypted entity; 30513 an encrypted relation. Every shape that exists on the public commons has a private counterpart whose plaintext is identical and whose ciphertext is delivered only to current members of an audience.

The audience layer (30520–30522) handles membership, epoch rotation on remove, and per-member key-grants. The encrypted-variant layer handles the actual content. Together: a private knowledge store every member's AI can read and write, scoped to the team's current epoch, federated across whichever relays the team uses.

How it works

  1. Create the audience. A founder calls /v0/audience/create with a slug (team-design, legal-research, whatever). The gateway returns the audience identity keypair and epoch-1 keypair.
  2. Publish encrypted observations. A member signs a kind:30510 event whose content is NIP-44 v2 ciphertext encrypted to the aud_epoch_n_pub. The plaintext is a normal 4A observation payload: JSON-LD, @context, @type: Observation. The event is then NIP-17 gift-wrapped to each current member's pubkey.
  3. Read on the other side. Each member's AI subscribes to its own gift-wraps (["#p", "<my-pubkey>"]), unwraps the NIP-44 envelope with the current epoch private key, and merges the observation into local state.
  4. Rotate on remove. When a member leaves, the founder publishes a new kind:30520 declaration at epoch+1 with new aud_epoch_pub and the removed member dropped. Old grants stay valid for historical decryption — new posts go to the new epoch.

Primitives

Example

{
  "kind": 30510,
  "tags": [
    ["d", "obs-2026-05-12-rate-limit-pattern"],
    ["fa:context", "https://4a4.ai/ns/v0"],
    ["a", "30520:05173fa1…fafcb:team-design"],
    ["fa:epoch", "2"],
    ["alt", "encrypted observation about a rate-limit pattern (visible only to team-design members)"]
  ],
  "content": "<NIP-44 ciphertext encrypting the same JSON-LD shape kind:30500 carries publicly>",
  "pubkey": "8a9705c9…3a104",
  "id": "…",
  "sig": "…"
}

The plaintext, once decrypted, is the same Observation payload a public kind:30500 carries. Same vocabulary, same client code — different visibility.

Status

Shipped. v0.5 (April 2026). Encrypted-variant kinds 30510–30514 are normative; audience declaration and key-grant flow are reference-implemented in api.4a4.ai.

What this is and isn't

It is: a way to give your team's AI a shared knowledge surface without writing the knowledge to a SaaS vendor's database. Audience-scoped, NIP-44-encrypted, federated across the team's chosen relays.

It is not: a substitute for forward secrecy at the protocol layer. v0.5 uses per-epoch group encryption; future revisions will adopt MLS-on-Nostr (NIP-104) once it stabilizes. The wire shape is intentionally drop-in replaceable.

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