Array Sync Rejects

A client pushes array ops to Origin over the sync WebSocket. Origin answers each op it does not apply with a typed reason. Each reason has one fixed class. The class tells the client what to do next. A client never parses the detail text.

Frames

An array frame whose body does not decode draws an ArrayReject with reason ShapeInvalid, an empty array name, and an all-zero HLC. That reject names no single op. The client holds every op it has in flight.

Advisory Refusals

An ArrayAck or ArrayCatchupRequest names no local op. Origin refuses one with ArrayAdvisoryRefused, never with ArrayReject, so a refusal never touches the client's push window. Its reason and class follow the table below. A catch-up for an array Origin does not hold draws ArrayUnknown. A catch-up that fails while Origin serves it draws the reason of the typed error.

Batches

Each op in an ArrayDeltaBatch applies on its own. A rejected op never stops the ops after it. Array ops are independent CRDT writes ordered by HLC, so no op in a batch depends on an earlier one.

ArrayOpResults.results holds one entry per entry of op_payloads, in the same order. Each entry carries the op's HLC and one outcome:

An op whose payload does not decode carries an all-zero HLC. Its position in results still names it.

An inbound array snapshot answers the same way. When the last chunk arrives, Origin attempts every op in the snapshot and sends one ArrayOpResults.

Reasons and Classes

Origin derives the reason from the typed engine error. It shares that classification with every other sync engine ack. A failure that applied nothing and can land later is EngineUnavailable.

Client Actions

Re-sending an op that did commit is safe. Origin dedups array ops by HLC, so the second apply reports Duplicate and changes nothing.