harness-adopt

harness-adopt is a skill for Claude Code, Codex from harnessworks/harness-starter-kit. It costs 43 tokens per session (256 once invoked), scanned A, original, MIT.

A repository setup skill that applies Harness Starter Kit guidance, checks, memory, and adoption reporting to an existing project.

In plain words
What is it for?
It is for inspecting a repository, adding or updating useful harness files, running relevant checks, and reporting what was adopted.
Why use it?
It helps add only the repository guidance that fits the project's current tools and practices instead of copying templates blindly.

Skill for Claude CodeCodex

Written for Claude Code and Codex: argument-hint in frontmatter, but also agents/openai.yaml present.

Part of the agent-skills plugin — 6 skills shipped together

Good fit It is for inspecting a repository, adding or updating useful harness files, running relevant checks, and reporting what was adopted.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/harnessworks/harness-starter-kit/harness-adopt
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 harnessworks/harness-starter-kit --skill harness-adopt
Clone the repo
git clone --depth 1 https://github.com/harnessworks/harness-starter-kit

Made for: Claude Code, Codex.

Or install agent-skills, the plugin that ships this one along with the rest of its 6 skills.

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.

agentmods badge for harness-adopt

README.md
[![agentmods](https://agentmods.dev/badge/skills/harnessworks/harness-starter-kit/harness-adopt/github.svg)](https://agentmods.dev/skills/harnessworks/harness-starter-kit/harness-adopt)
Your own site
<a href="https://agentmods.dev/skills/harnessworks/harness-starter-kit/harness-adopt"><img src="https://agentmods.dev/badge/skills/harnessworks/harness-starter-kit/harness-adopt/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.

agentmods 80×15 button for harness-adopt

Your own site · 80×15
<a href="https://agentmods.dev/skills/harnessworks/harness-starter-kit/harness-adopt"><img src="https://agentmods.dev/badge/skills/harnessworks/harness-starter-kit/harness-adopt.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 256 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00043 $0.00256
Opus 5 $0.00022 $0.00128
Sonnet 5 $0.00009 $0.00051
Haiku 4.5 $0.00004 $0.00026

Measured 10d ago against content hash ae28b219a570, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

harness-adopt 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 10d 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.

agent-skills/skills/harness-adopt/SKILL.md · 31 lines

What it actually says

Harness Adopt

Apply harness engineering to the current target repository.

Steps

  1. Read ../../references/package-contract.md.
  2. Read ../../references/adopt-workflow.md.
  3. If ./harness-starter-kit/docs/adoption-workflow.md exists in the target, prefer that canonical workflow.
  4. Inspect the target repository before editing.
  5. Add or update only the smallest useful harness artifacts that fit the target's existing architecture, tools, docs, commands, and conventions.
  6. Run relevant local checks.
  7. Finish with an adoption report, including task outcome evidence status for substantial harness work.

Boundaries

  • Do not blindly copy templates.
  • Do not replace existing target docs or config wholesale.
  • Do not add CI, pre-commit hooks, dependencies, or package scripts unless they match the target's existing workflow.
  • Treat a nested ./harness-starter-kit clone as read-only reference material.
Files

What ships with it

1 file 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.

  1. 10d ago First seen · 31 lines · 43 tokens per session scan A ae28b219a570

Subscribe to this mod's changes

harness-adopt is a skill published in the GitHub repository harnessworks/harness-starter-kit (113 stars, last pushed 2mo ago), licensed MIT. It adds 43 tokens to every session and 256 once invoked, about $0.0002 per session on Opus 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 2026-08-30.