sequenceDiagram
    participant U as User / Principal
    participant A as Agent A
    participant B as Agent B
    participant T as Tool / External Service
    participant L as Transparency / Audit Log

    U->>A: Request
    A->>B: Delegation with trace context
    B->>T: Tool call with GAID envelope
    T-->>B: Result
    B->>L: Signed Agent Action Receipt
    B-->>A: Result + receipt reference
    A->>L: Signed parent receipt
    A-->>U: Response
