How do I install the Harness skill?

Run npx skillmds@latest add aditikilledar/harness in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Harness safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Harness?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Harness free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Harness?

aditikilledar (@aditikilledar) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Harness by aditikilledar — Agent Skill

Name: Harness
Author: aditikilledar

Harness

Implements a high-reliability "Harness Engineering" loop using Planner, Generator, and Evaluator personas. Trigger when a user wants to "implement a feature," "start the harness," or "build with verification."

aditikilledar 0fa36d0 5 files · 252.2 KB Updated Sep 17, 2026

File contents

Objective

To replace one-shot code generation with a structured, self-correcting agentic loop that ensures all code is planned in YAML, implemented via best practices of coding, and verified by an adversarial evaluator before declared complete.

Instructions

1. Phase 0: Initialization

Read the repository README.md to understand the environment.
Create .harness/dev_init.md with instructions to run the development server for downstream agents.

2. Phase 1: Planning (The Planner)

Create a technical roadmap at .harness/[nickname].yaml.
Define specific, quantifiable Acceptance Criteria (AC) for every task.
Initialize an append-only log at .harness/progress.md to track all session activity.

3. Phase 2: Implementation (The Generator)

Select Task: Identify the next pending task based on depends_on logic.
Logic Synthesis: Perform an impact analysis and define a testing strategy before writing code.
Code Generation: Implement logic following SOLID, DRY, and KISS principles.
Atomic Updates: Every task completion requires a git commit and a progress entry.

4. Phase 3: Adversarial Evaluation (The Evaluator)

Hostile Barrier: Assume the Generator's output is riddled with bugs and happy-path logic.
Instant Death Gates: Immediately FAIL the task if there is a global regression, linting error, or any lazy code such as placeholders like TODO or FIXME.
AC Deep-Dive: Confirm every AC has a dedicated test and that test quality metrics like Mock Integrity and Coverage Stability are met.
Verdict: Return a binary PASS or FAIL. If FAIL, provide a root cause analysis.

5. Phase 4: Remediation and Reconciliation

Remediation: If the Evaluator returns FAIL, the Generator must suspend new work, reproduce the failure locally, and fix the logic until it passes evaluation.
Reconciliation: Once PASS is achieved, update the YAML task status to done and log the verification evidence including the git hash and test results in progress.md.

Reference

Persona - Planner: Focuses on structured YAML roadmap creation and task decomposition.
Persona - Generator: Focuses on defensive programming, architectural synthesis, and local verification.
Persona - Evaluator: Acts as the gatekeeper using a Zero-Trust approach to code quality.

---name: harnessdescription: Implements a high-reliability "Harness Engineering" loop using Planner, Generator, and Evaluator personas. Trigger when a user wants to "implement a feature," "start the harness," or "build with verification."---## ObjectiveTo replace one-shot code generation with a structured, self-correcting agentic loop that ensures all code is planned in YAML, implemented via best practices of coding, and verified by an adversarial evaluator before declared complete.## Instructions### 1. Phase 0: Initialization* Read the repository README.md to understand the environment.* Create .harness/dev_init.md with instructions to run the development server for downstream agents.### 2. Phase 1: Planning (The Planner)* Create a technical roadmap at .harness/[nickname].yaml.* Define specific, quantifiable Acceptance Criteria (AC) for every task.* Initialize an append-only log at .harness/progress.md to track all session activity.### 3. Phase 2: Implementation (The Generator)* Select Task: Identify the next pending task based on depends_on logic.* Logic Synthesis: Perform an impact analysis and define a testing strategy before writing code.* Code Generation: Implement logic following SOLID, DRY, and KISS principles.* Atomic Updates: Every task completion requires a git commit and a progress entry.### 4. Phase 3: Adversarial Evaluation (The Evaluator)* Hostile Barrier: Assume the Generator's output is riddled with bugs and happy-path logic.* Instant Death Gates: Immediately FAIL the task if there is a global regression, linting error, or any lazy code such as placeholders like TODO or FIXME.* AC Deep-Dive: Confirm every AC has a dedicated test and that test quality metrics like Mock Integrity and Coverage Stability are met.* Verdict: Return a binary PASS or FAIL. If FAIL, provide a root cause analysis.### 5. Phase 4: Remediation and Reconciliation* Remediation: If the Evaluator returns FAIL, the Generator must suspend new work, reproduce the failure locally, and fix the logic until it passes evaluation.* Reconciliation: Once PASS is achieved, update the YAML task status to done and log the verification evidence including the git hash and test results in progress.md.## Reference* Persona - Planner: Focuses on structured YAML roadmap creation and task decomposition.* Persona - Generator: Focuses on defensive programming, architectural synthesis, and local verification.* Persona - Evaluator: Acts as the gatekeeper using a Zero-Trust approach to code quality.

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