Architecture

The repository has two connected parts: a CS1 mod that exposes a local API and a Codex skill that teaches an agent how to use that API safely.

Runtime Shape

Codex agent
  -> PowerShell scripts
  -> http://127.0.0.1:32123
  -> SkylinesAgentBridge mod
  -> CS1 game thread queue
  -> game managers and save panel

The API server accepts local HTTP requests. State reads and mutating commands are dispatched through a game-thread queue so CS1 simulation objects are touched from the correct thread.

Source Layout

src/
├── ApiServer.cs
├── GameState.cs
├── RoadCommands.cs
├── BuildingCommands.cs
├── ZoneCommands.cs
├── BulldozeCommands.cs
├── SimulationCommands.cs
├── SaveCommands.cs
├── BatchCommands.cs
└── AgentBridge*.cs

ApiServer.cs maps HTTP paths to state builders or command handlers. GameState.cs builds JSON for city state. The command files keep mutating operations separated so an agent can choose one clear action at a time.

In-Game Notifications

Game-state API calls are written to a small in-game API console instead of a temporary toast. The console keeps recent request history, shows timestamps, and has a minimize button so it can stay available without covering the city.

/health is intentionally quiet because it can be called before a level is loaded.

Skill Metadata

SKILL.md contains the agent operating procedure. agents/openai.yaml provides the display name, default prompt, and implicit invocation setting for Codex skill surfaces.