Inventory synchronization

Map an installation connector's external location, channel, and SKU to a real tenant-owned SKU. Unknown or cross-tenant mappings fail without revealing whether the target exists.

An absolute command sets the external available total; a delta command applies a signed change. They are distinct operations and cannot share ambiguous payload semantics. Every command carries an idempotency key, monotonic externalVersion, sourceSystem, and causationId.

Duplicate, older, conflicting, or echoed causation is rejected or reported as an idempotent no-op. An external command cannot reduce stock below active platform reservations and cannot confirm or release an order reservation. Orders remain the authority for reserved and committed inventory.

Outbound events include the source and causation marker required to suppress connector echo. On concurrent local and external updates, use the configured conflict policy and optimistic version; never let a late callback overwrite a newer platform fact.