Nulnul Harness

NULNUL Harness

A project-aware AI coding harness for OpenAI Codex and Anthropic Claude Code. Tell it what you want. NULNUL loads only the project capabilities that matter, verifies the work with real checks, remembers verified experience, and evolves only when evidence justifies change.

English · 한국어

Quick start · What it does · In action · Evidence · v3.2.0 release

Outcome first · Verify the result · Keep only what earns its place

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Why NULNUL?

AI coding agents are powerful, but the project-specific setup around them tends to drift: rules get duplicated, skills accumulate, context goes stale, and “done” can mean “the model thinks it is done.”

NULNUL keeps that layer project-aware and evidence-driven.

Without NULNUL	With NULNUL
Re-explain project context every session	Resume from bounded verified project state
Load a familiar pile of rules and skills	Load only task-relevant capabilities
Trust a completion message	Run the repository's authoritative checks
Keep adding AI setup	Keep, improve, replace, merge, retire, or create only when evidence supports it
Rebuild useful context from chat history	Store verified Experience and retrieve only what is relevant

If the existing project setup is already the strongest justified path, adding nothing is a correct result.

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Quick start

Want to see the output first? NULNUL in Action collects a local booking UI/API demo, a synthetic research-workbook example, and the recorded 3.1.0 adoption of an existing project. Each case labels its evidence and limitations; these are not three independently verified customer projects or a new performance benchmark.

These installation commands target public v3.2.0, verified by fresh Claude and Meta adoption. Use a Codex or Claude Code build supporting plugin commands and follow its trust and permission prompts. A pinned installation does not automatically follow later releases.

OpenAI Codex

codex plugin marketplace add SeoNaRu/nulnul-harness --ref v3.2.0
codex plugin add nulnul-harness@nulnul-harness

Anthropic Claude Code

claude plugin marketplace add 'https://github.com/SeoNaRu/nulnul-harness.git#v3.2.0'
claude plugin install nulnul-harness@nulnul-harness

For first-time adoption, including a repository with an existing harness, ask:

Set up NULNUL for this repository, preserving its existing instructions and agent roles.
Then fix the booking API and verify that the existing behavior still passes.

For a project already using NULNUL, just ask for the work:

Fix the booking API and verify that the existing behavior still passes.

That is the intended normal workflow. You do not need to manually choose a Skill, create a Session, save Memory, pick an Agent topology, or run Evolution.

A task already covered by a complete local contract can stay on the Direct path. Installing the plugin does not force setup or durable Memory for every request.