Claude Code Harness

The AI writes the code.You still manage the work.

Delegate the plan, checks, and review.Judge the result.

Use your existing Claude Code, Codex CLI, Cursor, or Grok account.
Choose your tool · Try one small request

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Install and start

You need an installed, signed-in coding assistant and a project folder you can
write to. For an existing Harness setup, read the migration guide
before reinstalling or cleaning up files.

For Claude Code, open a terminal (the app where you type system commands) and run:

Then enter these commands inside Claude Code, one at a time:

/harness-setup prepares the project's instructions and checks. Review any
proposed project changes before accepting them. Installation time depends on
your existing setup and connection.

The Claude plugin ID is now harness; the repository and marketplace names
stay the same. If you installed the old claude-code-harness plugin, follow
Switch an existing Claude installation.
Updating the old ID alone does not rename it.
The tool table describes verified paths, not every future assistant version.

For other tools, choose the route in Install by tool.
The onboarding guide covers the same starting point
with more detail.

Your first request

You decide the outcome, the completion criteria, and the actions you authorize.
Review means checking the change separately from its implementation.

Start with one small change whose result you can check:

Harness drafts spec.md and Plans.md for you. Read the proposed behavior,
what it will change, how it will test the result, and anything still unknown.
Approve the plan or correct it before work starts.

Then run:

The first command works through the approved tasks. The second requests a
separate review. On Codex, use $harness-plan, $harness-work all,…