# N Agentic Harnesses Codex

Designs, evaluates, and improves agentic harnesses for developer tools, assistants...

- Repository: https://github.com/NateBJones-Projects/OB1 (4752 stars)
- Category: Design
- License: see repository
- Last updated: 2026-11-01
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add NateBJones-Projects/OB1 --skill n-agentic-harnesses-codex -g -a claude-code -y`
Codex: `npx skills add NateBJones-Projects/OB1 --skill n-agentic-harnesses-codex -g -a codex -y`
Cursor: `npx skills add NateBJones-Projects/OB1 --skill n-agentic-harnesses-codex -g -a cursor -y`
Gemini CLI: `npx skills add NateBJones-Projects/OB1 --skill n-agentic-harnesses-codex -g -a gemini-cli -y`

## Description

Designs, evaluates, and improves agentic harnesses for developer tools, assistants, workflow runtimes, copilots, and AI-powered products. Applies when work involves defining or reviewing tool-use architecture, permissions, workflow state, durability, context and memory systems, evaluation strategy, observability, user experience, or phased implementation plans for an agentic system.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# N Agentic Harnesses For Codex

Use this skill as a router for designing, building, and evaluating agentic harnesses.

Read only the files you need. Do not load the entire reference set unless the request genuinely spans multiple subsystems.

Default posture:

- Bias toward lean, solo-maintainable architecture.
- Start with a single-agent design unless clear constraints justify more.
- Require an evaluation plan even for greenfield builds.
- Prefer explicit system boundaries, permission policy, and workflow state over prompt cleverness.
- Translate ideas into implementation phases, success criteria, and failure tests.

## Step 1: Classify The Request

Choose one mode before reading reference files.

### `design`

Use when the user is creating a new harness, planning a major rebuild, or asking for architecture, MVP, or implementation sequencing.

Default reads:

- `references/01-principles-and-solo-dev-defaults.md`
- `references/02-harness-shapes-and-architecture.md`
- `references/08-design-and-build-playbook.md`

Add subsystem files only as needed.

### `evaluation`

Use when the user already has a harness and wants gaps, risks, missing primitives, UX upgrades, or architectural cleanup.

Default reads:

- `references/01-principles-and-solo-dev-defaults.md`
- `references/09-evaluation-and-improvement-playbook.md`

Add subsystem files only for the parts under review.

### `design + evaluation`

Use when the user wants a target architecture and a way to verify it, compare it with an existing system, or define acceptance criteria before building.

Default reads:

- `references/01-principles-and-solo-dev-defaults.md`
- `references/02-harness-shapes-and-architecture.md`
- `references/08-design-and-build-playbook.md`
- `references/09-evaluation-and-improvement-playbook.md`

## Step 2: Classify The Product Shape

Determine the closest product shape before going deeper:

The rest: https://github.com/NateBJones-Projects/OB1/blob/HEAD/skills/n-agentic-harnesses/variants/codex/SKILL.md