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DeepSeek Harness

Everyday tasks, coding, or your own harness—it starts here.

DeepSeek Harness is now in public preview worldwide and open source, with composable plugins that extend what agents can do.

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Meet DeepSeek Harness

Could you introduce yourself?

Thought for a while

I'm DeepSeek Harness, an open-source harness from DeepSeek built on Cordis's “everything is a plugin” architecture. Run me as a desktop app or launch the web UI from code.

I can help with:

1. Everyday work — Organize files, analyze data, draft docs, and create slides.Everyday work — Work with docs, data, and slides. 2. Coding — Explore repos, fix bugs, build features, and run tests.Coding — Fix bugs, build features, run tests. 3. Research — Find information, verify facts, and cite sources.Research — Find facts and cite sources. 4. Background tasks — Run scripts, batch-process files, and track progress.Background tasks — Run scripts and track progress. 5. Plugins — Add or build plugins to fit your workflow.Plugins — Add plugins or build your own.

And so much more...

Describe what you want to build, / commands, @ files or sessions

Workspace Write

DeepSeek-V41-Flash High

Expanding capabilities.

Everything is a plugin

Install plugins, or create them through chat in “Creator mode”, to extend tools, skills, and the interface.

Creator mode

Write a Pomodoro timer plugin for me.

Write a Pomodoro timer plugin for me.

Deep diving...

Load skillcordis-plugin-development

Readskills/cordis-plugin-development/SKILL.md

Thinkingshell.overlay is a frame-wide floating layer — the right target for an always-on-top window.

Inspect providers9 inspect providers

Query runtimeSlots.listSubTree

Writedsh-plugin-pomodoro-float/package.json+35 −0

Writedsh-plugin-pomodoro-float/client.js+638 −0

Tool callplugin\_manager · install\_bundle

Editdsh-plugin-pomodoro-float/client.js+5 −3

BashVerify live plugin state

Took 5m 24s

The floating Pomodoro timer is built, installed, and verified.

Official

Agent teamsExperimental

Auto approval reviewExperimental

Scheduled tasksExperimental

Voice inputExperimental

Terminal

Agent loop

Subagents

Installed

Pomodoro timer

Pomodoro timer

FocusShort break

25:0024:5924:5824:5724:5624:5524:5424:5324:5224:5124:5024:4924:4824:4724:4624:4524:4424:4324:4224:4124:4024:3924:3824:3724:36

Start focus

25:0024:5924:5824:5724:5624:5524:5424:5324:5224:5124:5024:4924:4824:4724:4624:4524:4424:4324:4224:4124:4024:3924:3824:3724:36Focus

Complete a range of tasks

Organize documents, analyze spreadsheets, and write code. Preview the results directly and refine them through conversation.

Brief.docxWord document

Data.xlsxExcel spreadsheet

index.htmlHTML page

label.tsTypeScript code

analyze.pyPython script

Report.pdfPDF document

README.mdMarkdown document

Brief.docxWord document

Data.xlsxExcel spreadsheet

index.htmlHTML page

Review · turn 1

@@ -8,3 +8,4 @@

88 `function label(name: string) {`

9−` return name;`

9+` const text = name.trim();`

10+` return text || 'Untitled';`

1011 `}`

Adapt to your workflow

Enable the Scheduled tasks plugin to start tasks anytime and run recurring work on schedule. Stay on top of progress and inspect tool call details when needed.

Every Friday at 17:00 Beijing time, summarize this week's project notes in a weekly report.

Deep diving...Worked

Create reminderSummarize this week's project notes in a weekly report.Weekly project report

IN`schedule_create`

{
  "prompt": "Summarize this week's project notes in a weekly report.",
  "title": "Weekly project report",
  "weekly": {"time":"17:00:00","time_zone":"Asia/Shanghai","weekdays":[5]}
}

Weekly project report

Scheduled forRepeatWeekly on Fri at 17:00 (Asia/Shanghai)StatusScheduled

Created “Weekly project report”, scheduled for Fridays at 17:00 Beijing time.

Weekly project reportWeekly on Fri at 17:00 (UTC+08:00 · China Standard Time)Open

Developer tools

Inspect execution traces and detailed runtime information to troubleshoot issues with tool calls and task execution.

DurationTurns⊟Calls⊟Search

InputModelTools

SYSTEMInitial System Prompt

Turn 1USERFirst run bash to print exactly NAVIGATION\_OK, then read nav-a.md and nav-b.md with two read calls, then reply with the single word FIRST\_DONE.

CONTEXTCurrent runtime context: workspace policy, available skills, and this turn's environment snapshot.

ASSISTANTRun bash to confirm the output, then read both navigation files.

TOOLbash{"command": "echo NAVIGATION\_OK", "description": "Print NAVIGATION\_OK"}→NAVIGATION\_OK

TOOLread{"file\_path": "nav-a.md"}→nav-a.md

TOOLread{"file\_path": "nav-b.md"}→nav-b.md

ASSISTANTFIRST\_DONE

Turn 2USERReply in markdown with a level-2 heading “Navigation Summary” and summarize both files.

ASSISTANTNavigation summary: alpha nav, beta nav, and the NAVIGATION\_OK output.

TOOLbash{"command": "ls -la", "description": "List workspace files"}→nav-a.md nav-b.md README.md

TOOLgrep{"pattern": "NAVIGATION", "path": "."}→2 matches

TOOLread{"file\_path": "README.md"}→README.md

ASSISTANTVerified the workspace listing and grep results; the task is complete.

TOOLTurn 1 · Step 1×

SummaryPayloadResultSchemaTiming

NAVIGATION\_OK

Started2026-08-12 17:30:52.637Duration34 msTiming sourceSession timestampsHierarchyAssistant Message

Developer experience

Start with one command

Install Node.js, then launch the Web UI with npx.

`$ npx @deepseek-ai/dsh web`Copy

Install from source

Clone the full source and follow the setup instructions in the repository.

`$ git clone https://github.com/deepseek-ai/deepseek-harness`Copy

Join the DSH plugin ecosystem

DeepSeek Harness is in preview, with evolving core plugins and APIs. We invite users and developers worldwide to explore the limits of intelligence together through open-source, reusable, and composable infrastructure.

View on GitHubDeveloper docsCommunity pluginsCordis paper