sequenceDiagram
    participant Client as useWorkflowExecution
    participant Stream as executionStream
    participant API as /api/workflows/execute
    participant Core as execution-core.ts
    participant DB as Database

    Note over Client: User triggers execution
    
    Client->>Client: Read latest workflow state from store
    Client->>Client: Build clientWorkflowState object
    Note over Client: BEFORE: conditionally sent override<br/>AFTER: always sent override
    
    Client->>Stream: execute({ workflowStateOverride })
    Note over Stream: workflowStateOverride always defined now
    
    Stream->>API: POST with workflowStateOverride
    API->>Core: executeWorkflowCore(snapshot)
    Note over Core: snapshot.metadata.workflowStateOverride
    
    alt workflowStateOverride present
        Core->>Core: Use client-side state (blocks, edges, loops, parallels)
        Note over Core: Validates against current client state<br/>DB may be 1-2 seconds behind
    else no override (old behavior)
        Core->>DB: Load draft state from DB
        Note over Core: Validates against DB state<br/>May be stale for 1-2 seconds
    end
    
    Core->>Core: Run validations on workflow state
    Core-->>API: Execution result
    API-->>Stream: SSE events stream
    Stream-->>Client: Callbacks invoked