Harness Score

What it does

When your agent uses it

• Tasks that involve Architecture decision records

Example prompts

• “/harness-score”

Requirements

• Node.js
• Pre-approved tools (allowed-tools): Bash

Workflow steps

4 steps, taken from the first numbered list in SKILL.md.

1. 1Shell out to npx metaharness score --json (single subprocess,
2. 2Parse the JSON shape: `{ harnessFit, compileConfidence, taskCoverage,
3. 3If --alert-on-fit-below N: exit 1 when harnessFit < N.
4. 4Output JSON (default) or markdown table.

What it can do on your machine

Read from SKILL.md and the folder at commit 58e0ae7. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Bash

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • npx
  • node

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md. Its commands use npx, which can reach the network depending on how they are called.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Harness Score loads about 605 tokens when it runs. Until then it costs about 81 tokens; SKILL.md has 194 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~81

When it runs · the whole SKILL.md, loaded when a task matches

~605

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NotePre-approves every shell command (allowed-tools: Bash)SKILL.md

  allowed-tools: Bash

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from ruvnet/ruflo at commit 58e0ae7, republished under its MIT licence (© ruvnet). 194 words, ~605 tokens.

name

harness-score

description

5-dimension harness readiness scorecard from `metaharness score <path>`. Returns harnessFit / compileConfidence / taskCoverage / toolSafety / memoryUsefulness + estCostPerRunUsd + scaffoldReady. Pure-read; subprocess invocation; degrades gracefully when MetaHarness is absent (ADR-150 architectural constraint).

allowed-tools

Bash

argument-hint

[--path .] [--alert-on-fit-below 70] [--format table|json]

node plugins/ruflo-metaharness/scripts/score.mjs --alert-on-fit-below 70 --format json

{
  "degraded": true,
  "reason": "metaharness-not-available",
  "hint": "Install with `npm i -D metaharness@~0.4.1` (pinned range — this plugin never fetches @latest) or verify network access for the one-time cache install."
}

© ruvnet, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in plugins/ruflo-metaharness/skills/harness-score of ruvnet/ruflo.

Open the folder on GitHubat commit 58e0ae7