evals

evals is a skill for Claude Code from igoruehara/spec-driven. It costs 55 tokens per session (363 once invoked), scanned A, original, MIT.

A specification-checking skill that measures whether a feature’s implementation covers its acceptance criteria, meaning the conditions that define when the feature works. It also reports open SPEC_DEVIATION items, which are differences between the agreed specification and the implementation.

In plain words
What is it for?
Use it to evaluate each feature, check whether acceptance criteria have tasks and test references, review edge cases, and produce a fidelity score with identified gaps.
Why use it?
It exposes missing traceability between requirements, development tasks, tests, and code, so gaps are easier to fix or formally accept.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

Needs its repository: it runs a file that does not travel with it, so clone the repository first. The line is node scripts/eval-spec-fidelity.mjs ..

Good fit Use it to evaluate each feature, check whether acceptance criteria have tasks and test references, review edge cases, and produce a fidelity score with identified gaps.

Compare 6 skills from other repositories ↓
Install

Getting it into your agent

It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.

Clone the repo
git clone --depth 1 https://github.com/igoruehara/spec-driven
agentmods
npx agentmods add skills/igoruehara/spec-driven/evals

Made for: Claude Code.

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 evals

README.md
[![agentmods](https://agentmods.dev/badge/skills/igoruehara/spec-driven/evals/github.svg)](https://agentmods.dev/skills/igoruehara/spec-driven/evals)
Your own site
<a href="https://agentmods.dev/skills/igoruehara/spec-driven/evals"><img src="https://agentmods.dev/badge/skills/igoruehara/spec-driven/evals/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 evals

Your own site · 80×15
<a href="https://agentmods.dev/skills/igoruehara/spec-driven/evals"><img src="https://agentmods.dev/badge/skills/igoruehara/spec-driven/evals.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 55 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 363 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 $0.00055 $0.00363
Opus 5.5 $0.00022 $0.00145
Sonnet 5.5 $0.00011 $0.00073
Haiku 4.5 $0.00006 $0.00036

Measured 1mo ago against content hash d755c86570b3, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

evals 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.

template/.claude/skills/evals/SKILL.md · 27 lines

What it actually says

Skill: Evals de fidelidade spec→código

Mede se o que foi construído reflete a spec — a métrica de qualidade da saída do agente. Duas camadas: determinística (script) e de julgamento.

1. Camada determinística

node scripts/eval-spec-fidelity.mjs .

Reporta, por feature: AC totais, cobertos por task, referenciados em teste/código e SPEC_DEVIATION abertos. Falha (exit 1) se algum AC não tem task — rastreabilidade quebrada. Referência em teste é aviso até a feature ser implementada.

2. Camada de julgamento (o script não pega isso)

  • O teste de cada AC-N realmente exercita o Given/When/Then — ou só cita o ID num teste vazio?
  • A implementação cobre os casos de borda e respeitou o "Fora de escopo" da spec?
  • Os SPEC_DEVIATION abertos têm resolução (corrigir código ou atualizar a spec/ADR)?

Saída

Score por feature + os gaps. Complementa o /validar (UAT de uma feature) com uma visão de fidelidade do portfólio. O mesmo eval roda na CI (esteira.yml) — aqui é o complemento com julgamento.

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. 1mo ago First seen · 27 lines · 55 tokens per session scan A d755c86570b3

Subscribe to this mod's changes

evals is a skill published in the GitHub repository igoruehara/spec-driven (213 stars, last pushed 2mo ago), licensed MIT. It adds 55 tokens to every session and 363 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 2026-08-30.

Related

Other skills, from other repositories

research-engineer

An uncompromising Academic Research Engineer. Operates with absolute scientific rigor, objective criticism, and zero flair. Focuses on theoretical correctness, formal verification, and optimal implementation across any required technology.

davila7/claude-code-templates · 43 tokens

eval-dataset-design

A guide to creating reliable test sets for AI agents. Each evaluation task includes the request, the simulated user's behaviour, a reset starting state, and a success check that can be independently verified.

bojieli/ai-agent-book · 138 tokens

tika-eval-compare

Compare extracts from two Tika builds over a corpus to detect regressions in content, encoding, exceptions, and embedded-document handling. Use for "compare before/after extracts", "eval this change against the corpus".

apache/tika · 50 tokens

cua-driver

Use Cua Driver for desktop or browser tasks that are awkward or unavailable through Bash/APIs, or when the user explicitly wants GUI interaction: app testing, visual bug reproduction, form filling, calendar entry, screenshots, and demo recording. Also covers Cua setup; not OpenAI Codex Computer Use or web research.

davidondrej/skills · 68 tokens

jetson-validate-image

Use after jetson-flash-image to run static BSP checks, on-target smoke/regression tests on a flashed DUT, or both. Not for build or flash steps. Triggers: validate bsp, on-target validation.

NVIDIA/skills · 50 tokens

atmos-validation

Validate Atmos projects, components, arbitrary JSON Schema inputs, EditorConfig, and GitHub Actions; use affected-file selection and native CI annotations.

cloudposse/atmos · 31 tokens