flowchart LR
    subgraph issuer["Human / Issuer"]
        I["👤 Human"]
    end

    subgraph agent_layer["AI Agent"]
        A["🤖 AI Agent"]
    end

    subgraph merchant_layer["Merchant Server"]
        M["🏪 Merchant\nx402 + LedgerFlow Verifier"]
    end

    subgraph facilitator_layer["LedgerFlow Facilitator"]
        F["⚡ Facilitator\nPayment Routing"]
    end

    subgraph settlement["Settlement Rails"]
        EVM["EVM"]
        SOL["Solana"]
        EXC["Exchange"]
        FIAT["Traditional Gateway"]
    end

    I -->|"issue warrant\n(signed, scoped, short-lived)"| A
    A -->|"x402 PaymentRequired\n+ LedgerFlow extension"| M
    M -->|"verify & forward\nx402 payload"| F
    F -->|"route to rail"| EVM
    F -->|"route to rail"| SOL
    F -->|"route to rail"| EXC
    F -->|"route to rail"| FIAT

    style issuer fill:#e8f4fd,stroke:#4a90d9,stroke-width:2px,color:#1a1a2e
    style agent_layer fill:#fef9e7,stroke:#f0b429,stroke-width:2px,color:#1a1a2e
    style merchant_layer fill:#eafaf1,stroke:#27ae60,stroke-width:2px,color:#1a1a2e
    style facilitator_layer fill:#f4ecf7,stroke:#8e44ad,stroke-width:2px,color:#1a1a2e
    style settlement fill:#fdedec,stroke:#e74c3c,stroke-width:2px,color:#1a1a2e
    style I fill:#d6eaf8,stroke:#2980b9,color:#1a1a2e
    style A fill:#fdebd0,stroke:#e67e22,color:#1a1a2e
    style M fill:#d5f5e3,stroke:#1e8449,color:#1a1a2e
    style F fill:#e8daef,stroke:#7d3c98,color:#1a1a2e
    style EVM fill:#fadbd8,stroke:#c0392b,color:#1a1a2e
    style SOL fill:#fadbd8,stroke:#c0392b,color:#1a1a2e
    style EXC fill:#fadbd8,stroke:#c0392b,color:#1a1a2e
    style FIAT fill:#fadbd8,stroke:#c0392b,color:#1a1a2e