How do I install OpenHarness?

Install OpenHarness with a single command: npx mdskills install HKUDS/openharness. This downloads the skill files into your project and your AI agent picks them up automatically.

What platforms support OpenHarness?

OpenHarness works with Claude Code. Skills use the open SKILL.md format which is compatible with any AI coding agent that reads markdown instructions.

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OpenHarness

Name: OpenHarness: AI Agent Skill
Brand: HKUDS
Availability: InStock
Author: HKUDS

Official

Ultra-lightweight pure-Python alternative to Claude Code from HKU Data Intelligence Lab. ~98% of Claude Code's core tool capabilities in only 11,733 lines of code. Fully compatible with Anthropic Skills and the Claude Code plugin ecosystem. Supports any OpenAI-compatible model.

by HKUDS

npx mdskills install HKUDS/openharness

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Harness details

Kind: Standalone runtime
UI: CLI
Install: pip
Platforms: macOSLinuxWindows
Capabilities: Session managementContext injectionModel-agnostic

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SKILL.md

1# OpenHarness
2 
3## Description
4Ultra-lightweight pure-Python alternative to Claude Code from HKU Data Intelligence Lab. ~98% of Claude Code's core tool capabilities in only 11,733 lines of code. Fully compatible with Anthropic Skills and the Claude Code plugin ecosystem. Supports any OpenAI-compatible model.
5 
6## When to Use This Skill
7 
8Use this skill when the user needs help with tasks related to this domain.
9 
10## Instructions
11 
12Add your instructions here.

Full transparency — inspect the skill content before installing.

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