A multi-agent workflow for complex software tasks that coordinates planning, implementation, evaluation, end-to-end checks, and retrospective learning.

Use it to move from a brainstormed design and reviewed specification through autonomous execution, quality checks, pull-request creation, and a project retrospective.

It divides large work into checkpoints and uses fresh reviewers to reduce drift between the original plan and the implementation.

harness — Skill for Claude Code and Codex by AuroraPixel

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add AuroraPixel/ai-native-harness-skill --skill harness

Clone the repo

git clone --depth 1 https://github.com/AuroraPixel/ai-native-harness-skill

Made for: Claude Code, Codex.

Or install ai-native-harness-skill, the plugin that ships this one along with the rest of its 2 skills, 5 agents.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/aurorapixel/ai-native-harness-skill/harness/github.svg)](https://agentmods.dev/skills/aurorapixel/ai-native-harness-skill/harness)

Your own site

<a href="https://agentmods.dev/skills/aurorapixel/ai-native-harness-skill/harness"><img src="https://agentmods.dev/badge/skills/aurorapixel/ai-native-harness-skill/harness/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/aurorapixel/ai-native-harness-skill/harness"><img src="https://agentmods.dev/badge/skills/aurorapixel/ai-native-harness-skill/harness.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 130 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 2,257 The whole file, excluding the scripts and references it only reads on demand.

Security scan C 2 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin 89% copy Near-identical to another mod in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00130	$0.02257
Opus 5	$0.00065	$0.01128
Sonnet 5	$0.00026	$0.00451
Haiku 4.5	$0.00013	$0.00226

Measured 8d ago against content hash 2f85990a770f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade C, and why

harness scanned grade C with 2 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.

The scan reads SKILL.md. This mod also ships 5 executable files (hooks/phase-guard.mjs, scripts/_cohort_spec.py, scripts/claude-agent-invoke.sh, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Reads agent configuration directoriesmediumAgent snooping

.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.

Verify (review roles): `{ find ~/.claude/plugins -path '*/plugins/ai-native-harness-skill/agents/harness-*.md' -type f 2>/dev/null; ls plugins/ai-native-harness-skill/agents/harness-*.md 2>/dev/null; ls ~/.claude/agents/

Enumerates other installed skillsmediumAgent snooping

Other skills' SKILL.md files reveal prompts, capabilities and secrets that should be invisible to peers.

If not found, try `find ~/.claude/skills -path "*/harness/scripts/harness-engine.sh"` or `find ~/.codex/skills -path "*/harness/scripts/harness-engine.sh"` as fallback. In a checked-out repo, `plugins/ai-native-harness-s

Origin

This is a copy

89% identical to harness — 41 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

plugins/ai-native-harness-skill/skills/harness/SKILL.md · 160 lines

How it starts

The opening of the file, as written. The whole thing — 160 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Harness — Multi-Agent Orchestration

Orchestrate complex tasks through Planning -> Generation -> Evaluation -> Retro. Fresh sub-agents per checkpoint prevent drift. Retro accumulates learning across tasks.

Recommended Workflow

Session 1 (Claude Code) → Brainstorm + Spec → Spec review with cross-model evaluator
    ↓ spec approved
Session 2 (Codex)       → Execute checkpoints → Evaluate → E2E → Full-verify → PR → Retro
    ↕ Claude CLI as review-loop peer (cross-model quality gate)

Session 1: Claude Code for interactive discovery — brainstorming + multi-turn Q&A to establish requirements. After the user approves the brainstormed design, spec drafting and the Spec Evaluator review loop run autonomously (agent-to-agent until consensus). See references/planning-protocol.md "Post-Brainstorming Autonomy".
Session 2: Codex for autonomous execution — implementation, evaluation, PR creation, retro. Claude CLI serves as cross-model reviewer via review-loop.
Both hosts support both phases. The above is the recommended flow, not a hard constraint.

Prerequisites

superpowers plugin installed (Claude Code): Generator preloads TDD, verification, debugging skills
Reviewer role definitions: harness-convention-scout.md, harness-spec-evaluator.md, harness-generator.md, harness-evaluator.md, harness-retro.md — ship with this plugin at plugins/ai-native-harness-skill/agents/; user overrides may live at ~/.claude/agents/harness-*.md
python3 on PATH (engine JSON operations)
git repository initialized
For Codex-hosted execution: claude CLI on PATH for sub-agent dispatch and review-loop

Verify (Claude Code): claude plugin list | grep superpowers Verify (review roles): { find ~/.claude/plugins -path '*/plugins/ai-native-harness-skill/agents/harness-*.md' -type f 2>/dev/null; ls plugins/ai-native-harness-skill/agents/harness-*.md 2>/dev/null; ls ~/.claude/agents/harness-*.md 2>/dev/null; } | sort -u Verify (Codex): codex --version && claude --version

Read the full file on GitHub · 160 lines

Files

What ships with it

10 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

8d ago First seen · 160 lines · 130 tokens per session scan C 2f85990a770f

Subscribe to this mod's changes

harness is a skill published in the GitHub repository AuroraPixel/ai-native-harness-skill (11 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 130 tokens to every session and 2,257 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it C with 2 findings (reads agent configuration directories, enumerates other installed skills). It is 89% identical to harness, differing in 41 lines, and is treated as a copy.

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