Borrowing it
Nothing to install: this file belongs to Chachamaru127/codex-harness. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Chachamaru127/codex-harness/main/.codex/skills/harness-init/SKILL.mdgit clone --depth 1 https://github.com/Chachamaru127/codex-harnessWrote 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.
[](https://agentmods.dev/skills/chachamaru127/codex-harness/harness-init)<a href="https://agentmods.dev/skills/chachamaru127/codex-harness/harness-init"><img src="https://agentmods.dev/badge/skills/chachamaru127/codex-harness/harness-init/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.
<a href="https://agentmods.dev/skills/chachamaru127/codex-harness/harness-init"><img src="https://agentmods.dev/badge/skills/chachamaru127/codex-harness/harness-init.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00061 | $0.00921 |
| Opus 5.5 | $0.00024 | $0.00368 |
| Sonnet 5.5 | $0.00012 | $0.00184 |
| Haiku 4.5 | $0.00006 | $0.00092 |
Grade A, and why
harness-init scanned grade A with 0 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 1mo ago.
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.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 92 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Harness Init Skill
Sets up a project so VibeCoder can start development with natural language only. Completes with minimum 1 question, ready to start development immediately.
Quick Reference
- "Want to launch a new project fastest" → this skill
- "Leave it to you" / "Quickly" → proceed with defaults, no questions
- "With Next.js + Supabase" → technology specification
- "Introduce harness to existing project" → analyze existing code
Deliverables
- Real project generation (e.g., create-next-app) + initial setup
- Prepare
Plans.md/AGENTS.md/CLAUDE.md/.claude/ - Optional: Codex CLI compatibility (
.codex/+AGENTS.md) - Environment diagnosis → SSOT initialization → Final validation
- → Ready to run Plan→Work→Review immediately
Usage
/harness-init # Interactive setup (min 1 question)
/harness-init blog --mode=solo # With partial specification
/harness-init --stack=next-supabase # Specify tech stack
Feature Details
| Feature | Reference |
|---|---|
| Execution Flow | See references/execution-flow.md |
| Smart Defaults | See references/smart-defaults.md |
| Generated Files | See references/generated-files.md |
Optimized Flow
Before: Up to 11 dialogue rounds After: Minimum 1, maximum 2 dialogue rounds
Step 1: Unified question (1 time)
├─ What are you building?
├─ Who will use it?
└─ Leave it to me or detailed settings?
Step 2: Confirmation (skip if "leave it to me")
└─ Tech stack + project name
→ Execute setup (includes background analysis)
Step 3: Completion report
Arguments
| Argument | Description | Example |
|---|---|---|
[project description] |
What to build | "EC site" |
--mode |
solo / 2agent | --mode=solo |
--stack |
Tech stack | --stack=next-supabase |
--name |
Project name | --name=my-app |
--lang |
Language | --lang=en |
What ships with it
4 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.
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.
- 1mo ago First seen · 92 lines · 61 tokens per session scan A 073f3fbc026f
harness-init is a skill published in the GitHub repository Chachamaru127/codex-harness (2 stars, last pushed 8mo ago), licensed MIT. It adds 61 tokens to every session and 921 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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