# MeshService — Agent Notes

## Purpose

Generic decentralized service layer. Any P2P service following Announce→Query→Response→Reserve can be built on this.

## Quick Commands

```bash
# Run tests
cargo test

# Run examples
cargo run --example fapp_service
cargo run --example housing_service
cargo run --example multi_service
```

## Key Files

| File | Purpose |
|------|---------|
| `src/router.rs` | Main entry point, `ServiceRouter` |
| `src/message.rs` | `ServiceMessage` struct |
| `src/services/fapp.rs` | FAPP implementation (reference) |
| `src/services/housing.rs` | Housing (second service example) |

## Adding a New Service

1. Create `src/services/myservice.rs`
2. Define payload structs with serde
3. Implement `ServiceHandler`
4. Add to `src/services/mod.rs`
5. Add service ID to `lib.rs`

## Wire Format

64-byte header (fixed) + signature (64 bytes) + payload (CBOR) + optional verifications.

See `src/wire.rs` for encoding/decoding.

## Integration with quicprochat-p2p

The `ServiceRouter` is transport-agnostic. To integrate:

```rust
// Receive from transport
let msg = wire::decode(&incoming_bytes)?;
let action = router.handle(msg, Some(sender_pubkey))?;

// Handle action
match action {
    ServiceAction::StoreAndForward => {
        // Re-broadcast msg.forwarded() via transport
    }
    ServiceAction::Respond(response) => {
        // Send response back
    }
    _ => {}
}
```

## Costs

- No external API calls
- Pure Rust, runs locally
- Memory: Store grows with cached announces (configurable limits)