Download and install DeepSeek Harness: npm, npx or source

DeepSeek Harness (DSH) is officially distributed in exactly two places: the @deepseek-ai/dsh package on npm and the deepseek-ai/deepseek-harness source repository on GitHub. There is no third-party "download site" — if a page tells you to grab an installer from somewhere else, it is not official.

DSH is a command-line tool, so "downloading" it really means letting npm pull the official package onto your machine — there is no traditional installer. First recognize the official channels, then pick an install method that fits how you plan to use it.

Official download channels: the npm package and the GitHub repo

DeepSeek Harness has two official download channels: @deepseek-ai/dsh on the npm registry and the deepseek-ai/deepseek-harness repository on GitHub; every run command on the official site and docs starts with @deepseek-ai/dsh (source).

Run through these four checks before downloading to make sure you are on an official channel:

1. Check the package name on npm: the official package is @deepseek-ai/dsh, hosted at https://www.npmjs.com/package/@deepseek-ai/dsh; other npm packages with "dsh" in the name are usually community plugins — this one package is the harness itself (source).
2. Check the organization on GitHub: the official repository is deepseek-ai/deepseek-harness, owned by the deepseek-ai organization, the official DeepSeek AI GitHub account; verify the org name before cloning (source).
3. The official site and docs give commands, not installers: https://www.deepseek.com/harness/ and https://deepseek-harness.github.io/deepseek-harness/guide/quickstart only provide commands such as npx @deepseek-ai/dsh web — there is no "click to download" entry (source).
4. Skip third-party download sites: pages in search results called "DeepSeek Harness download", "cracked" or "localized" versions are not official distribution points. DSH is open source; there is no reason for the official project to hand out code anywhere other than npm and GitHub.

How to install: npx one-liner, npm global install, or source build

There are exactly three ways to install DeepSeek Harness: the npx one-liner for a quick try, an npm global install for daily use, and a source build for modifying code — all of them need Node.js 18 or newer first.

Set up the environment:

1. Install Node.js 18 or newer from https://nodejs.org (LTS recommended), or via nvm, accepting the default options;
2. Open a new terminal window and run node -v; v18 or higher means you are ready;
3. Run npm -v too; a version number means the package manager works (npx ships with npm).

Option 1: npx one-liner (fastest, for a quick try)

1. Run npx @deepseek-ai/dsh web in a terminal;
2. The first run fetches the latest package from npm, and later runs check for updates;
3. Open http://127.0.0.1:3080 in your browser; the Web UI loading means success (source).

The npx method does not write to your PATH or take global space, so it is easy to walk away from.

Option 2: npm global install (for daily use)

1. Run npm install -g @deepseek-ai/dsh and wait for the install to finish;
2. Run dsh --help; seeing the launcher usage means the install worked;
3. If you get command not found (on Windows: "'dsh' is not recognized"): the npm global bin folder is not on your PATH. Run npm prefix -g to find it; on macOS/Linux add it with export PATH="$(npm prefix -g)/bin:$PATH" and retry in the same terminal; on Windows just open a new terminal (the Node.js installer already added the global folder to PATH);
4. Start it with dsh web; the Web UI opens at http://127.0.0.1:3080;
5. Update with npm update -g @deepseek-ai/dsh and remove it with npm uninstall -g @deepseek-ai/dsh (source).

Option 3: source build (for modifying code and contributing)

1. Make sure Git and pnpm are installed first; if pnpm is missing, run npm install -g pnpm, then verify with pnpm -v;
2. Run git clone https://github.com/deepseek-ai/deepseek-harness.git;
3. Install dependencies: cd deepseek-harness && pnpm install;
4. Build the artifacts: pnpm run build (a production run requires building first);
5. Start it: pnpm dsh web, then open http://127.0.0.1:3080 (source).

A one-line rule of thumb: use npx to see what DSH looks like, use an npm global install when you plan to type dsh regularly, and build from source when you want to debug or change the kernel.

Verifying the install: version number and port 3080

Verify a DeepSeek Harness install in two steps: check the official latest version with npm view @deepseek-ai/dsh version, then confirm the Web UI loads at http://127.0.0.1:3080.

1. Run npm view @deepseek-ai/dsh version; npm returns the latest official version (this works without installing);
2. After a global install, run npm ls -g @deepseek-ai/dsh to see your local version; matching numbers mean you have the official latest;
3. Start with dsh web or npx @deepseek-ai/dsh web, open http://127.0.0.1:3080, and the page loading means the install succeeded;
4. If the browser cannot reach 3080, it is usually a port conflict or an old Node.js; check node -v is ≥ v18 first.

After installing DSH: configure a model, add plugins, watch for preview changes

Once DeepSeek Harness is installed, open Settings → Model in the Web UI to save a model API key, then install plugins as needed; DSH is a developer preview, so check for breaking changes before upgrading (source).

1. In the Web UI, go to Settings → Model, enter and save your model API key; the model route becomes available immediately;
2. Install plugins with dsh plugin --profile web add <package or repo> and restart dsh web for them to take effect; full steps in How to install DSH plugins;
3. Watch the official repo's release notes: DSH is in developer preview and upgrades may break compatibility, so read the releases and docs before updating the harness itself.

Once DSH is running, instead of gambling on third-party download sites, browse the community-run DSH Plugin Hub: it hosts a curated catalog, installs and removes plugins in one click, shows a confirmation dialog before every install, and keeps system logs you can check when something goes wrong.