The guest agent runs inside the VM to provide enhanced integration features (clipboard, window enumeration, metrics, snapshots quiesce, etc.).

• Language: Rust
• Runtime: Minimal dependencies; async (tokio) optional later.
• Build: Cross-compile for aarch64-unknown-linux-gnu and Windows ARM (future).

1. HELLO handshake + capabilities list.
2. HEARTBEAT every 5s with minimal metrics (uptime, load if available).
3. Clipboard request/offer pipeline (text/plain only first).
4. Window enumeration (Phase B of coherence) — Linux/X11 prototype.

agent/
  Cargo.toml        (to be added)
  src/
    main.rs         (entry point)
    protocol.rs     (frame encode/decode mirroring host)
    clipboard.rs    (feature module)
    windows/        (window enumeration backends)
      x11.rs
      wayland.rs
    metrics.rs

fn main() -> anyhow::Result<()> {
    let mut conn = VsockConnection::connect(3, 7000)?; // cid=host, port=7000 example
    conn.send_hello()?;
    loop {
        conn.poll()?; // read frames
        // schedule heartbeat
    }
}

• Will require Rust stable toolchain.
• Cross target add: rustup target add aarch64-unknown-linux-gnu.
• Static linking optional (musl) if minimal footprint desired.

• Validate all host-originated messages & enforce size constraints.
• No arbitrary file system access beyond required shared folder paths.

This is a placeholder; implementation to follow in future iteration.