Plan. Work. Review. Ship.
Turn Claude Code into a disciplined development partner.
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Why Harness?
Claude Code is powerful. Harness turns that raw capability into a delivery loop that is easier to trust and harder to derail.
The 5 verb skills keep setup, plan, work, review, and release on one path. The TypeScript guardrail engine protects execution, and validation can be rerun when you need proof.
Compared With Popular Claude Code Harnesses
What matters here is not the theoretical ceiling of Claude Code. It is what becomes the default operating model once you install a harness.
This is a user-facing workflow snapshot as of 2026-03-06, not a popularity contest.
Full notes and source links: docs/github-harness-plugin-benchmark.md
The card below focuses on what becomes the default operating path after install.
Claude Harness is the clearest fit if you want the default path itself to stay planned, guarded, reviewed, and rerunnable.
Supported baseline and latest verified snapshot: see Claude Code Compatibility.
Requirements
- Claude Code v2.1+ (Install Guide)
- Node.js 18+ (for TypeScript core engine & safety hooks)
Install in 30 Seconds
# Start Claude Code in your project
claude
# Add the marketplace & install
/plugin marketplace add Chachamaru127/claude-code-harness
/plugin install claude-code-harness@claude-code-harness-marketplace
# Initialize your project
/harness-setup
That's it. Start with /harness-plan.
🪄 TL;DR: Verified Work All
Don't want to read all this? Just type:
/harness-work all
One command runs the full loop after plan approval. Plan → Parallel Implementation → Review → Commit.
⚠️ Experimental workflow: Once you approve the plan, Claude runs to completion. Validate the success/failure contract in docs/evidence/work-all.md before depending on it in production.
The 5 Verb Workflow
0. Setup
/harness-setup
Bootstraps project files, rules, and command surfaces so the rest of the loop runs against the same conventions.
1. Plan
/harness-plan
"I want a login form with email validation"
Harness creates Plans.md with clear acceptance criteria.
2. Work
/harness-work # Auto-detect parallelism
/harness-work --parallel 5 # 5 workers simultaneously
Each worker implements, runs a preflight self-check, and waits for an independent review verdict before completion.
3. Review
/harness-review
| Perspective | Focus |
|---|
| Security | Vulnerabilities, injection, auth |
| Performance | Bottlenecks, memory, scaling |
| Quality | Patterns, naming, maintainability |
| Accessibility | WCAG compliance, screen readers |
4. Release
/harness-release
Packages the verified result into CHANGELOG, tag, and release handoff steps after implementation and review are complete.
Safety First
Chachamaru127