score-harness

score-harness is a skill for Claude Code from ruvnet/metaharness. It costs 0 tokens per session (740 once invoked), scanned A, original, MIT.

A scorecard for judging a generated coding harness across five areas: repository understanding, agent usefulness, MCP safety, test coverage, and publishing readiness. A coding harness is the project setup that lets agents work with a codebase and its tools.

In plain words
What is it for?
Use it to assess a harness, detect missing tests or release files, check tool-safety settings, and report whether it reaches the defined release grade.
Why use it?
It turns several quality checks into one score, grade, and status block for a README. MCP refers to the tool-connection system used by agents, and the scorecard checks whether its access is controlled.

Skill for Claude Code

Written for Claude Code: a Claude Code plugin manifest. Also seen: reads .claude/ paths; mentions Codex.

Part of the agent-harness-generator plugin — 14 skills, 1 plugin shipped together

Good fit Use it to assess a harness, detect missing tests or release files, check tool-safety settings, and report whether it reaches the defined release grade.

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

Made for: Claude Code.

Or install agent-harness-generator, the plugin that ships this one along with the rest of its 14 skills, 1 plugin.

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 score-harness

README.md
[![agentmods](https://agentmods.dev/badge/skills/ruvnet/metaharness/score-harness.svg)](https://agentmods.dev/skills/ruvnet/metaharness/score-harness)
Your own site
<a href="https://agentmods.dev/skills/ruvnet/metaharness/score-harness"><img src="https://agentmods.dev/badge/skills/ruvnet/metaharness/score-harness.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 740 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. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
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 $0.00000 $0.00740
Opus 5 $0.00000 $0.00370
Sonnet 5 $0.00000 $0.00148
Haiku 4.5 $0.00000 $0.00074

Measured 9d ago against content hash 4093fd09e4c4, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

score-harness 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 9d 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.

.claude-plugin/skills/score-harness/SKILL.md · 77 lines

How it starts

The opening of the file, as written. The whole thing — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.

score-harness

Codex skill: 5-dimension harness scorecard with README-ready badges (iter 111 → iter 114).

What it does

Every generated harness gets a single 0-100 score and a 6-field badge block. The user roadmap target: A grade (>=85) without manual edits.

Dimension Weight Reads
Repo understanding 25% .harness/manifest.json (surface + kernel_version + host)
Agent usefulness 25% src/agents/*.ts + .claude/skills/* + .claude/commands/* counts
MCP safety 20% .harness/mcp-policy.json (default-deny + audit + perm gates)
Test coverage 15% __tests__/ + npm test + .github/workflows/
Publish readiness 15% witness.json + sbom.json + package.json#bin

Grade + exit code:

Grade Range Exit
A 85-100 0 — the user's target
B 70-84 0
C 50-69 1 (needs work)
F 0-49 2 (blocked)

Badge block (the 6-field shape)

{
  "score": 87,
  "mcpRisk": "Low",
  "releaseReady": true,
  "testsDetected": true,
  "sbom": true,
  "witnessSigned": true
}

mcpRisk is one of None / Low / Medium / High. Drop this block into the generated harness README as visible badges — see ADR-030 for the propagation discipline.

Usage from Codex

/score-harness path=./my-harness
/score-harness path=./my-harness bundle=true

Equivalent CLI

harness score ./my-harness                # text + bars + dimension breakdown
harness score ./my-harness --json         # 6-field badges JSON
harness score ./my-harness --bundle       # ADR-031 schema-1 envelope
harness score ./my-harness --out badges.json
  • validate-harness (iter 22) — release-readiness umbrella that the score subcommand inherits signals from
  • diag-harness (iter 70) — kernel-version skew (one of the Repo-understanding signals)
  • threat-model (iter 114) — focused MCP threat artifact

See also

Read the full file on GitHub · 77 lines

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. 9d ago First seen · 77 lines · 0 tokens per session scan A 4093fd09e4c4

Subscribe to this mod's changes

score-harness is a skill published in the GitHub repository ruvnet/metaharness (639 stars, last pushed today), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 740 tokens. 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.

Related

Other skills, from other repositories

C31-review

Reviews code changes using dynamically selected reviewer personas, then runs a verify-work pass: UAT walkthrough, verifier validation, and decision coverage logging. Writes memory/.planning/phases/XX-VERIFICATION.md.

ChianW/C31 · 32 tokens

C31-coding-discipline

A disciplined workflow for coding tasks that requires a failing test before production code, a plan, isolated work for larger changes, review, and final verification. TDD, or test-driven development, means writing the failing test first, then making it pass.

ChianW/C31 · 84 tokens

neuron-evaluation-engineer

Create and run AI evaluations with datasets, assertions, and output drivers in Neuron AI. Use this skill whenever the user mentions evaluation, testing AI systems, creating evaluators, dataset-driven testing, assertion-based validation, or wants to measure AI system performance. Also trigger for tasks involving…

neuron-core/neuron-ai · 77 tokens

neuron-test-engineer

Write tests for Neuron AI agents, RAG systems, workflows, and tools using the built-in testing utilities. Use this skill when the user mentions testing agents, writing unit tests, mocking AI providers, testing tool execution, verifying RAG retrieval, testing workflow behavior, or creating test cases for Neuron AI…

neuron-core/neuron-ai · 94 tokens

hk-rca

Interactive Root Cause Analysis enforcer. Guides you through the 7-step RCA protocol: Reproduce, Locate, Hypothesis, Failing Test, Fix, Verify Live, Document. Use when debugging a bug, investigating a failure, or when something unexpected happened. This skill gates each step — it won't let you skip to a fix without…

deepklarity/harness-kit · 111 tokens

hk-local-run-spec

Plan and execute an odin spec. Handles working directory, auth, nested-session detection, and post-run diagnostics. Use whenever the user wants to run a spec, test a spec, or do a smoke test. Triggers on: 'run this spec', 'test this spec', 'odin plan', 'smoke test', or /hk-local-run-spec.

deepklarity/harness-kit · 78 tokens