What is DeepSeek Harness (DSH)? The "everything is a plugin" agent framework

DeepSeek Harness (DSH) is an open-source agent framework by DeepSeek AI with the CLI tool dsh, and its core idea is "everything is a plugin".

Overview

DeepSeek Harness is described in its official repository as an agent harness — a framework that provides a standard way to wire models, tools, interfaces and skills together. Its CLI tool is dsh, which composes capabilities into a runnable agent system through a plugin mechanism (source).

Core idea: everything is a plugin

DSH abstracts nearly every extension point into a plugin. Model adapters, tools, interfaces, skills, MCP servers, hook policies, protocol bridges, subagents, and even full distributions all plug into the framework instead of being hardcoded into the kernel.

The benefit is clear: adding a capability never requires changing the kernel — just install a plugin. The community groups these plugins into eleven primary categories: interface, session, memory, tools, agent, workflow, integration, model, dev, data, and fun.

Powered by Cordis

DSH's plugin runtime is based on Cordis. Cordis handles plugin loading, registration, lifecycle management and dependencies, so multiple plugins can compose reliably.

Current status: developer preview

DSH is currently in developer preview, iterating fast with breaking compatibility changes. That means plugin compatibility must be tracked continuously — which is exactly why the community hub exists: to mark each plugin's supported DSH version and compatibility status.

The official team keeps the kernel and does not accept external PRs, leaving ecosystem growth to the community. The dsh-plugin.org hub fills the "registry" layer that the official team has not built yet.

Next steps

If you haven't installed DSH yet, see How to install DeepSeek Harness, then browse the plugin hub and try a few plugins.

Source: deepseek-ai/deepseek-harness