ArenaOS Quickstart
Start the complete local platform, inspect its registries, and launch a real persisted run.
Start both services
Install once, then use the unified development command. It starts the Fastify control plane on port 4000 and the Next.js judge experience on port 3000.
pnpm install
pnpm devOpen the platform
The Worlds registry discovers every registered environment from the API. Choose one of the six showcase worlds, configure its participants, and launch a run.
http://localhost:3000/environmentsVerify the control plane
The web app proxies REST traffic to Fastify while live run events stream over WebSocket. A healthy response confirms the backend is ready.
curl http://127.0.0.1:4000/api/healthTry the CLI
The CLI uses the same registries and orchestrator as the web experience. Start by listing the worlds and agents available in the running codebase.
pnpm arena environments
pnpm arena agentsAdd model access when needed
OpenRouter and OpenAI keys stay server-side. Copy the example environment file, add only the keys you intend to use, and restart the development process. Default agents work without external model access.
Copy-Item .env.example .env.local
# Add OPENROUTER_API_KEY and/or OPENAI_API_KEY
pnpm dev