Agent = Model + Harness

Harness

keeps agents working in real-world environments

The model is the soul of an agent.

A harness lets an agent understand its environment, use tools, and keep working in real-world settings.

Cordis kernel

The Cordis kernel manages plugin mounting, unmounting, and dependencies. Agent capabilities live in the plugins.

Capabilities as plugins

Plugins provide every agent capability, including models, tools, skills, sessions, sandboxes, storage, loops, scheduling, and the UI. Cordis services and events let the plugins work together.

Compose with configuration

Developers can select, swap, or extend any capability in configuration without changing the DeepSeek Harness source code.

Customize your DeepSeek Harness

Get started

Try it now or install from source

Quick start

Install Node.js, then launch the Web UI with npx.

$ npx @deepseek-ai/dsh web

Install from source

Clone the full source and follow the setup instructions in the repository.

$ git clone…