DeepSeek Harness Guide

Install DeepSeek Harness (npx dsh web)

How to install DeepSeek Harness with npx @deepseek-ai/dsh web or from source. API key, localhost:3080, Windows notes.

Last updated: 2026-08-14

DeepSeek Harness (dsh) is a local agent runtime. v0.1 is a Web UI, not a CLI. MIT license. Official repo: deepseek-ai/deepseek-harness.

npx: the official one-liner

npx @deepseek-ai/dsh web

Opens the DeepSeek Harness Web UI at http://127.0.0.1:3080. You need Node.js.

This is the command on the official landing page and README. If a blog tells you to npm i -g deepseek-harness, ignore it unless the official README changes.

Install DeepSeek Harness from source

git clone https://github.com/deepseek-ai/deepseek-harness.git
cd deepseek-harness
pnpm install
pnpm run build
pnpm dsh web

Use this when you want to read the Cordis plugins or pin a commit. Developer preview will break.

DeepSeek API key

The harness is not a hosted coding agent. You bring a key from platform.deepseek.com. Typical models: deepseek-v4-flash and deepseek-v4-pro. Put the key where the Web UI settings ask for it — do not paste it into this website.

Windows and “no CLI”

There is no official dsh CLI/TUI in v0.1. On Windows, npx still works if Node is on PATH. Community options:

See DeepSeek Harness TUI.

If it does not start

  • Confirm node -v works.
  • Try another port only if 3080 is taken; the default is what the official docs use.
  • Delete a stale npx cache if an old package shadows @deepseek-ai/dsh.
  • Read GitHub Discussions. This site is unofficial.

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