tl;dr: DeepSeek has released Harness, an open-source agent framework available as a desktop app for macOS/Windows or web UI, built on Cordis's plugin-based architecture. It handles tasks like file organization, coding, research, and scheduled background jobs, with a "Creator mode" for building new plugins via chat. Developers can launch it instantly with `npx @deepseek-ai/dsh web` or clone the repo from GitHub.