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STELLA

System for Testing and Engineering LLM-based Conversational Agents

STELLA is a NestJS-based control plane for managing conversational AI sessions with LiveKit WebRTC integration and Kubernetes agent orchestration.

What is STELLA?

STELLA provides a complete infrastructure for building, deploying, and managing voice-enabled AI agents. It handles:

  • Real-time Communication: WebRTC-based voice and data streaming via LiveKit
  • Agent Orchestration: Automatic Kubernetes pod management for AI agents
  • Session Management: Track conversations, participants, and messages
  • Flexible Architecture: Support for multiple agent types with customizable pipelines

Architecture

ExternalLiveKitWebRTC SFUExternalUserBrowserExternalLLM APIOpenAI / OllamaKubernetes Clusternamespace: ai-agentsFrontendReact :5173BackendNestJS :3000Agent PodPythonPostgreSQL:5432STTSherpa / WhisperTTSPiper / KokoroHTTPWebRTCRESTPrismaK8s APIAudioAPIgRPCgRPC

Hover over a component to see details

Key Components

ComponentDescription
LiveKitExternal WebRTC media server (cloud-hosted or self-hosted)
Backend APINestJS server managing sessions, agents, and LiveKit tokens
Frontend UIReact app for real-time voice/text communication
STT/TTS ServicesMicroservices for speech recognition and synthesis
Agent PodsPython conversational AI agents, created per session

Features

Project & Session Management

  • Create and organize multiple projects
  • Track sessions, agents, and activity per project
  • Get aggregated statistics

Agent Orchestration

  • Deploy conversational AI agents to Kubernetes
  • Automatic Secret and Pod creation
  • Pass plan configurations via environment variables
  • Monitor agent status and logs
  • Graceful shutdown and cleanup

LiveKit Integration

  • JWT token generation for secure room access
  • WebRTC-based real-time communication
  • Data channel for text messages

Data Persistence

  • PostgreSQL database via Prisma ORM
  • Track participants, messages, and room events
  • Timeline view combining messages and events

Next Steps