What it does
Harness is a plugin for Claude Code, Anthropic's AI coding assistant. You describe your project or field in a sentence, and it designs a team of AI agents with set roles, plus the skills they use.
It picks how the agents should work together, for example in a pipeline or with one supervisor, and adds checks to filter out answers that look right but are wrong.
A second command improves the team over time based on your feedback.
Who it's for
Developers who use Claude Code and want to set up multi-agent workflows.
Can I use it without coding?
Developers only. It is installed inside Claude Code and used in coding projects. New to this? Start here.
Can I run it?
- Cost
- Free, but needs an AI accountThe software is free, but it uses an online AI service (like OpenAI or Anthropic), which usually charges for use.
- Runs on
- Mac, Windows, Linux
- Computer
- An ordinary computer is fine
- Privacy
- Sends what you give it to an online service
- API key
- Not needed
Try it
- Add the Harness plugin from its marketplace inside Claude Code.
- Ask Claude Code to build a harness for your project.
Using Claude Code, Cursor or another AI coding assistant? Paste the prompt and it will walk you through the setup.New to this?
Before you install
- Only download from the official GitHub page. Copies with similar names exist for many popular projects.
- License (Apache-2.0): Permissive: free to use, change and share, including for business.
- What you type or upload is sent to an online service. Avoid sharing private or sensitive information.
- More on staying safe