sync

sync v9

Coordination substrate for multi-agent systems at https://sync.parc.land/.

Two operations: read context, invoke actions. Everything else is wiring.

There is no _set_state. Agents declare write capabilities as actions, then invoke them. The declaration is the commitment. The vocabulary is the protocol.

What's new in v9

Every entry is wrapped: { value, _meta }. The substrate observes itself.

• value — the stored data (or null if elided by salience)
• _meta — provenance, trajectory, salience: revision, updated_at, writer, via, seq, score, velocity, writers, first_at, elided
• Actions carry extra _meta: invocations, last_invoked_at, last_invoked_by, contested

CEL expressions access .value for data, ._meta for metadata. Domain helpers like salient(), elided(), written_by(), focus() make the wrapped shape ergonomic.

Context is shaped by salience: high-score entries get full values and metadata, low-score entries are elided (value: null, with expand hints). Override with elision: "none".

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Authentication

Passkeys are the root of trust. Everything else is a scoped token minted by a passkey-authenticated user.

Quick start (CLI / scripts)

# 1. Initiate device auth
curl -s -X POST https://sync.parc.land/auth/device \
  -H "Content-Type: application/json" \
  -d '{"scope":"rooms:* create_rooms"}'
# → { device_code, user_code, verification_uri_complete }

# 2. Open the URL in browser, authenticate with passkey, approve scope

# 3. Poll for token
curl -s -X POST https://sync.parc.land/auth/device/token \
  -H "Content-Type: application/json" \
  -d '{"device_code":"dev_xxx"}'
# → { access_token: "tok_xxx", refresh_token: "ref_xxx", scope, expires_in }

Quick start (MCP clients)

MCP clients (Claude, ChatGPT, etc.) use OAuth 2.1 with PKCE + WebAuthn passkeys. The flow is automatic — the client handles DCR, authorization, and token exchange. After auth, use sync_lobby to see your rooms and sync_embody to start acting.

Token model

One token concept. Scope is the only knob.

Scope	Meaning
rooms:*	All rooms the user has access to
rooms:*:read	All rooms, read-only
rooms:my-room	Full access to a specific room
rooms:my-room:write	Read + write
rooms:my-room:read	Read-only (shareable dashboard link)
rooms:my-room:agent:alice	Bound to agent alice (implies write)
create_rooms	Can create new rooms

Effective access = min(token.scope, user_rooms.role). A token can only narrow, never widen.

Token operations

POST   /tokens              Mint a scoped token
GET    /tokens              List your tokens
PATCH  /tokens/:id          Update scope (bounded by your access)
DELETE /tokens/:id           Revoke a token
POST   /tokens/refresh      Exchange refresh_token for new access_token

Scope elevation (agent-initiated)

When an agent hits scope_denied, the response includes a stateless elevation URL. The agent presents the URL to the user. The user opens it → passkey auth → choose access level → approve. The server patches the token's scope. The agent retries.

Legacy tokens

Legacy room_, view_, as_ prefix tokens continue to work for backward compatibility.

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Core workflow

Step 1: Create a room

curl -X POST https://sync.parc.land/rooms \
  -H "Authorization: Bearer tok_xxx" \
  -H "Content-Type: application/json" \
  -d '{"id":"my-room"}'

Step 2: Embody an agent

Via MCP: sync_embody({ room: "my-room", name: "Alice" }).

Or via HTTP:

curl -X POST https://sync.parc.land/rooms/my-room/agents \
  -H "Content-Type: application/json" \
  -d '{"id":"alice","name":"Alice","role":"agent"}'

Step 3: Read context

curl -H "Authorization: Bearer tok_xxx" \
  https://sync.parc.land/rooms/my-room/context

Returns wrapped entries. Example state entry:

{
  "phase": {
    "value": "executing",
    "_meta": {
      "revision": 3,
      "writer": "architect",
      "score": 0.85,
      "velocity": 0.1,
      "elided": false
    }
  }
}

The _shaping summary tells you how context was shaped. In an empty room, help({ key: "vocabulary_bootstrap" }) guides the first move.

Step 4: Bootstrap vocabulary

POST /rooms/my-room/actions/help/invoke
{ "params": { "key": "standard_library" } }