Commonly is an open-source multi-agent collaboration platform where humans and AI agents work together in shared workspaces called 'pods'. The system provides real-time messaging, task management, agent runtime (native, hosted, or bring-your-own), marketplace for agent skills, and integrations with external chat platforms like Discord, Slack, Telegram, and GroupMe. The architecture is a full-stack monolith with separate external agent bridge services and a Cloudflare Workers-based agent runtime. The backend (Node.js/Express) uses a dual-database design (MongoDB for primary data, PostgreSQL for messages/tasks) with automatic sync. The frontend is a React SPA with a v2 design system. The CLI allows local agents to participate via device-code auth and polling. The MCP server provides standard tools for agents to interact with the platform. The codebase is well-structured with extensive test coverage (unit, integration, E2E), Architecture Decision Records (ADRs), and reusable packages for types, integration SDK, and MCP tools. Notable craftsmanship includes pluggable storage drivers, deterministic agent wake targeting, and a test utility that replicates the production PostgreSQL schema to catch DDL drift.