How to Install DeepSeek Harness (DSH) on Windows
This guide takes you from a clean Windows computer to a working DeepSeek Harness Web UI. You do not need to clone the source code for the normal quick-start method.
DeepSeek Harness is still evolving quickly. Commands and UI labels may change between releases, so verify against the official project if something looks different.
Before you start
For the official npm quick start, DeepSeek says to install Node.js and then launch DSH with npx. The Web UI is served on your own computer at 127.0.0.1:3080 by default.
Install Node.js
Open the official Node.js website and install a current supported release. Keep the default installer options unless you already manage Node.js with another tool.
The simplest DSH launch command uses npx, which is included with npm when Node.js is installed.
Replace this placeholder with a real screenshot showing the official Node.js download page and Windows installer.
Open Windows Terminal
Press the Windows key, type Terminal, then open Windows Terminal. PowerShell is fine for this tutorial.
Show the Start menu search result for Windows Terminal, then the PowerShell prompt.
Check that Node.js works
Run both commands below. If each command prints a version number, your Node.js installation is ready.
node --versionnpm --versionPS C:\Users\YourName> node --version v22.x.x PS C:\Users\YourName> npm --version 10.x.x
If Windows says node or npm is not recognized, close Terminal, reopen it, and try again. If the error remains, reinstall Node.js.
Launch DeepSeek Harness
Run the official quick-start command:
npx @deepseek-ai/dsh webThe first launch may download the package before starting the local Web UI. Keep the terminal window open while you use DSH.
This is the npm quick-start command published by DeepSeek for DeepSeek Harness.
Capture the terminal after running npx @deepseek-ai/dsh web, including the local Web UI address if shown.
Open the DSH Web UI
Open a browser and visit the default local address:
http://127.0.0.1:3080127.0.0.1 means the page is being served from your own computer. It is not a public website.
Show the first DSH Web UI screen at 127.0.0.1:3080.
Configure your DeepSeek model
Open the model/settings area in the DSH interface and add your DeepSeek credentials. DeepSeek's API currently uses https://api.deepseek.com as the OpenAI-compatible base URL, with current model identifiers including deepseek-v4-flash and deepseek-v4-pro.
Do not publish screenshots that expose your full API key. Blur or replace it before adding screenshots to this website.
Show the DSH model configuration screen, but use a fake or blurred API key.
Choose a workspace
Select the local project folder you want DSH to work with. For your first test, create a simple empty folder such as C:\\Projects\\dsh-test and use that as the workspace.
Use a test folder first. Once you understand what tools your selected mode can use, you can point DSH at a real project.
Show the workspace selector and a harmless test project folder.
Start your first session
Create a new session and start with a simple, reversible task. For example:
If the model responds and completes the task, your Windows setup is working.
Show the prompt, model response, and resulting README file without exposing private project data.
Common Windows errors
node is not recognized
Node.js is either not installed or the terminal has not picked up the updated PATH. Reopen Terminal after installation. If necessary, reinstall Node.js.
npx is not recognized
Confirm npm works with npm --version. A normal Node.js installation includes npm and npx.
Port 3080 is already in use
Another process may already be using the default Web UI port. First check whether DSH is already running in another terminal or browser tab before killing processes.
401 / authentication error
Recheck the API key in your model configuration. Make sure you copied the key itself, not the API URL.
The model does not respond
Confirm your network connection, API key, model identifier and provider settings. DeepSeek's current API model IDs can change, so check the official API docs if the UI differs from this guide.
FAQ
Do I need Git to use DSH on Windows?
Not for the normal npm quick start. Git is only needed if you want to clone and run the source repository.
Do I need to install DeepSeek Harness globally?
No. The official quick start runs it with npx @deepseek-ai/dsh web.
What address should I open?
The official repository says the Web UI is served at http://127.0.0.1:3080 by default.
Is DeepSeek Harness stable?
It is currently a developer preview. DeepSeek explicitly warns that compatibility-breaking changes will happen while the project evolves.
DeepSeek Harness official site, the official deepseek-ai/deepseek-harness repository, and DeepSeek API documentation. This site is independent and is not affiliated with or endorsed by DeepSeek.