Illustrated setup guide · 2026

DeepSeek Harness Setup Guide

The model is the brain; the harness is everything wrapped around it — context, tools, plugins, MCP servers, permissions, memory. DeepSeek Harness installs in about five minutes and runs on any model you point it at: GLM, Ollama, even Claude. This walkthrough follows a real install frame by frame.

TL;DR — what you're setting up

  • The model is the brain. The harness is everything around it: context, tools, plugins, MCP servers, permissions, memory. DeepSeek Harness ships all of it with every decision still open.
  • Install takes about five minutes: one command in your terminal, and a local web dashboard opens automatically.
  • You don't have to use DeepSeek's API. Add GLM, a free Gemini tier, a local Ollama model — or even your Anthropic key to run Claude inside the harness.
  • Every run is traceable down to each tool call payload, and you can kill a task mid-flight and resume it with its context intact.

DeepSeek Harness Setup: A Free Claude Code You Own In 10 Minutes

Video by:Sharbel A.13 min

Watch on YouTube

Screenshots in this guide come from the video above; copyright belongs to its creator, who is credited here and linked at each step's timestamp. The written steps are our own.

Quick start: install in about five minutes

  1. 1

    Open the site and grab the install command

    The DeepSeek Harness site fronts the project — "Everything is a plugin" is the literal design principle. Open the GitHub repo from the homepage buttons and copy the one-line install command.

    DeepSeek Harness website homepage showing the Everything is a plugin tagline with View on GitHub and Developer docs buttons
    The project homepage links both the GitHub repo and the developer docs.Watch at 1:58
  2. 2

    Run the install in your terminal

    Paste the command and let it run — about five minutes. When it finishes, the terminal prints the local dashboard URL (http://127.0.0.1:3880) and opens your browser automatically. Add --no-open if you'd rather open it yourself.

    Terminal finishing the DeepSeek Harness install with the local dashboard URL http://127.0.0.1:3880 ready to open
    Install finished — the dashboard is served locally on port 3880.Watch at 2:37
  3. 3

    Skip the API key prompt for now

    First launch asks for an official DeepSeek API key. You don't need one: click "Configure later" and add whichever provider you actually use in the next step.

    DeepSeek Harness first-run API key dialog with a Configure later button for skipping the official DeepSeek provider
    The first-run dialog — "Configure later" skips the official provider.Watch at 2:55

Connect any model you want

  1. 4

    Add your first model provider

    Go to Settings → Models → Add provider. In the video the author connects a GLM subscription (listed as Zai), but the same dialog accepts DeepSeek, OpenAI, Anthropic, Bedrock, Vertex, and more.

    DeepSeek Harness Models settings listing the DeepSeek and Zai providers next to the Add provider buttons
    Two providers active — the model is a plugin, not a lock-in.Watch at 3:15
  2. 5

    Or connect a local model with Ollama

    "Add a custom provider" takes a provider ID, a display name, a base URL, and an API protocol (openai-completions works for Ollama). Local weights are the only genuinely uncapped free path — hosted free tiers all have limits.

    Custom provider form in DeepSeek Harness with Ollama base URL and openai-completions protocol fields before Create provider
    Custom provider form — point it at your Ollama base URL and create.Watch at 3:42

Everything is a plugin

  1. 6

    Browse the plugin panel

    Settings → Plugins lists every capability in the harness — commands, UI commands, feedback loops — each individually toggleable between Default and Enabled. The sidebar itself is a plugin too.

    DeepSeek Harness Plugins settings showing command and ui-command plugins with Enabled and Default toggles
    The plugin list — everything you see can be switched off.Watch at 5:32
  2. 7

    Switch on creator mode

    Creator mode is a preset that loads the plugin-development tooling automatically, so the agent can build plugins for you instead of just using them.

    DeepSeek Harness creator mode prompt asking for a plugin that fires a desktop notification when a run finishes
    Creator mode preloads the plugin development tooling.Watch at 6:00
  3. 8

    Ask for your first plugin in plain English

    The plugin built in the video: "Add a plugin that fires a desktop notification when a run finishes, and puts the token count and what it cost me into the notification." Send it as a normal chat message.

    DeepSeek Harness chat running the desktop notification plugin prompt with context injection and tool calls visible
    One sentence is a spec — the agent writes and installs the plugin.Watch at 6:08
  4. 9

    Watch the plugin fire on the next run

    When a run completes, the notification appears with the token count and cost. In the video the first version had unreadable black-on-black text — one follow-up message fixed the colors, and the plugin kept working.

    DeepSeek Harness chat confirming the desktop notification plugin fired a Run finished alert with session token stats
    Run finished — the agent confirms the notification, stats included.Watch at 9:26

Trajectory: watch every call, resume any run

  1. 10

    Open the Trajectory tab and read everything

    Every run keeps a full trajectory: the exact system prompt, context injected word for word, which skills loaded and why, every tool call with its payload, result, and timing. Not a summary — the actual log.

    Trajectory tab in DeepSeek Harness with color-coded turn timeline and every assistant and tool call logged
    Color-coded turns plus every tool call with payload and result.Watch at 7:46
  2. 11

    Kill a run mid-task — then resume it

    Nothing is hard-coded, so nothing has to restart. Kill a run partway through and resume: the trajectory shows the workspace query that restores the same context, user preferences, and tool state. The README warns about breaking changes (it's a developer preview) — this is the safety net.

    DeepSeek Harness trajectory log showing a cordis workspace query resuming a killed run with its runtime context
    Resuming picks up the same context the killed run had.Watch at 8:02

DeepSeek Harness FAQ