Agent skill

Agent Eval

by affaan-m in affaan-m/ECC

カスタムタスクでコーディングエージェント(Claude Code、Aider、Codex など)をヘッドツーヘッドで比較し、合格率、コスト、時間、一貫性のメトリクスを測定します

MITAuto-check passedDevelopment

Install Agent Eval

skills CLI
$ npx skills add affaan-m/ECC --skill agent-eval -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI
$ gh skill install affaan-m/ECC agent-eval --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy
$ git clone --depth 1 https://github.com/affaan-m/ECC.git skills-src && mkdir -p .claude/skills && cp -r skills-src/docs/ja-JP/skills/agent-eval .claude/skills/agent-eval && rm -rf skills-src

Use ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.

Claude Code skills documentation · loads skills from .claude/skills/

Facts

Skill name
agent-eval
GitHub stars
276k
Token cost
~786 tokens
SKILL.md length
99 words
Files
1
Skills in repo
673
Repo updated
First seen
Licence
MIT

At a glance

カスタムタスクでコーディングエージェント(Claude Code、Aider、Codex など)をヘッドツーヘッドで比較し、合格率、コスト、時間、一貫性のメトリクスを測定します

  • Works in 3 steps: タスクの定義 → エージェントの実行 → 結果の比較
  • Development work in your project
  • SKILL.md covers 起動タイミング, インストール, コアコンセプト and ワークフロー, plus 3 more sections
  • Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Agent Eval is an agent skill from affaan-m/ECC. カスタムタスクでコーディングエージェント(Claude Code、Aider、Codex など)をヘッドツーヘッドで比較し、合格率、コスト、時間、一貫性のメトリクスを測定します

Its SKILL.md is about 790 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Development. It works with Git. The repository describes itself as: The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cursor and beyond. The licence is MIT.

When your agent uses it

  • Development work in your project

Example prompts

  • “/agent-eval”

Requirements

  • Docker

Workflow steps

3 steps, taken from the step headings in SKILL.md.

  1. タスクの定義
  2. エージェントの実行
  3. 結果の比較

What it can do on your machine

Read from SKILL.md and the folder at commit ef648e0. It shows what the files ask for, not the result of running them.

  • Tool permissions

    Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

    From allowed-tools in the SKILL.md frontmatter.

  • Runs code

    No scripts in the folder and no shell commands in SKILL.md (its code samples are yaml and bash).

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

  • Network

    Links to these hosts (documentation or services it may open):

    • github.com

    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

Agent Eval loads about 786 tokens when it runs. Until then it costs about 25 tokens; SKILL.md has 99 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it
~25
When it runs · the whole SKILL.md, loaded when a task matches
~786

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

Auto-check passed

The automated check found no risky patterns in SKILL.md.

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 affaan-m/ECC at commit ef648e0, republished under its MIT licence (© affaan-m). 99 words, ~786 tokens.

Download SKILL.mdSave it as .claude/skills/agent-eval/SKILL.md (or your agent's skills folder).
name
agent-eval
description
カスタムタスクでコーディングエージェント(Claude Code、Aider、Codex など)をヘッドツーヘッドで比較し、合格率、コスト、時間、一貫性のメトリクスを測定します
origin
ECC
tools
Read, Write, Edit, Bash, Grep, Glob

エージェント評価スキル

再現可能なタスクでコーディングエージェントをヘッドツーヘッドで比較するための軽量 CLI ツールです。「どのコーディングエージェントが最適か?」という比較はすべて感覚に頼りがちです — このツールはそれを体系化します。

起動タイミング

  • 自分のコードベースでコーディングエージェント(Claude Code、Aider、Codex など)を比較する
  • 新しいツールやモデルを採用する前にエージェントパフォーマンスを測定する
  • エージェントがモデルやツールを更新した際にリグレッションチェックを実行する
  • チームにデータに基づいたエージェント選択の判断を提供する

インストール

注意: agent-eval はソースを確認した後、リポジトリからインストールしてください。

コアコンセプト

YAML タスク定義

タスクを宣言的に定義します。各タスクは何をするか、どのファイルを操作するか、成功をどう判定するかを指定します:

yaml
name: add-retry-logic
description: Add exponential backoff retry to the HTTP client
repo: ./my-project
files:
  - src/http_client.py
prompt: |
  Add retry logic with exponential backoff to all HTTP requests.
  Max 3 retries. Initial delay 1s, max delay 30s.
judge:
  - type: pytest
    command: pytest tests/test_http_client.py -v
  - type: grep
    pattern: "exponential_backoff|retry"
    files: src/http_client.py
commit: "abc1234"  # 再現性のために特定コミットに固定
Git ワークツリー分離

各エージェント実行は独自の git ワークツリーを取得します — Docker 不要。これにより再現性の分離が提供され、エージェントが互いに干渉したりベースリポジトリを破壊したりしません。

収集メトリクス
メトリクス測定内容
合格率エージェントはジャッジをパスするコードを生成できたか?
コストタスクあたりの API 費用(利用可能な場合)
時間完了までのウォールクロック秒数
一貫性繰り返し実行での合格率(例:3/3 = 100%)

ワークフロー

1. タスクの定義

タスクごとに 1 つの YAML ファイルを持つ tasks/ ディレクトリを作成します:

bash
mkdir tasks
# タスク定義を作成(上記のテンプレートを参照)
2. エージェントの実行

タスクに対してエージェントを実行します:

bash
agent-eval run --task tasks/add-retry-logic.yaml --agent claude-code --agent aider --runs 3

各実行:

  1. 指定されたコミットから新しい git ワークツリーを作成
  2. エージェントにプロンプトを渡す
  3. ジャッジ基準を実行
  4. 合格・不合格、コスト、時間を記録
3. 結果の比較

比較レポートを生成します:

bash
agent-eval report --format table
Task: add-retry-logic (3 runs each)
┌──────────────┬───────────┬────────┬────────┬─────────────┐
│ Agent        │ Pass Rate │ Cost   │ Time   │ Consistency │
├──────────────┼───────────┼────────┼────────┼─────────────┤
│ claude-code  │ 3/3       │ $0.12  │ 45s    │ 100%        │
│ aider        │ 2/3       │ $0.08  │ 38s    │  67%        │
└──────────────┴───────────┴────────┴────────┴─────────────┘

ジャッジタイプ

コードベース(決定論的)
yaml
judge:
  - type: pytest
    command: pytest tests/ -v
  - type: command
    command: npm run build
パターンベース
yaml
judge:
  - type: grep
    pattern: "class.*Retry"
    files: src/**/*.py
モデルベース(LLM-as-judge)
yaml
judge:
  - type: llm
    prompt: |
      Does this implementation correctly handle exponential backoff?
      Check for: max retries, increasing delays, jitter.

ベストプラクティス

  • 3〜5 タスクから始める — おもちゃの例ではなく、実際のワークロードを代表するタスク
  • エージェントごとに少なくとも 3 試行実行する — エージェントは非決定論的なので分散を把握する
  • タスク YAML でコミットを固定する — 日や週をまたいで結果が再現可能になる
  • タスクごとに少なくとも 1 つの決定論的ジャッジを含める(テスト、ビルド)— LLM ジャッジはノイズを加える
  • 合格率と一緒にコストを追跡する — 10 倍のコストで 95% のエージェントが正しい選択でない場合もある
  • タスク定義をバージョン管理する — それらはテストフィクスチャであり、コードとして扱う

リンク

© affaan-m, 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 docs/ja-JP/skills/agent-eval of affaan-m/ECC.

Open the folder on GitHubat commit ef648e0

Compare with similar skills

Agent Eval next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.

Agent Eval compared with similar skills
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Code Design Rationale Investigatorcursor/plugins10k9 repos~2.6kAutomated safety check: PassNone
Contributor-First PR MergeHKUDS/OpenHarness16k1 repos~847Automated safety check: PassMIT
Finishing A Development Branchfarm-fe/farm5.6k34 repos~1.8kAutomated safety check: PassMIT

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Works with

Categories

Questions about Agent Eval

What does Agent Eval do?

カスタムタスクでコーディングエージェント(Claude Code、Aider、Codex など)をヘッドツーヘッドで比較し、合格率、コスト、時間、一貫性のメトリクスを測定します. Agent Eval is an agent skill from affaan-m/ECC.

When should I use Agent Eval?

Agent Eval fits situations like: development work in your project.

How do I install Agent Eval in Claude Code?

Run `npx skills add affaan-m/ECC --skill agent-eval -a claude-code`. Or copy the skill folder (docs/ja-JP/skills/agent-eval in affaan-m/ECC) into .claude/skills/agent-eval in your project. Claude Code loads it when a task matches its description.

How do I install Agent Eval in Codex?

Run `npx skills add affaan-m/ECC --skill agent-eval -a codex`. Or copy the skill folder (docs/ja-JP/skills/agent-eval in affaan-m/ECC) into .agents/skills/agent-eval in your project. Codex loads it when a task matches its description.

Can I use Agent Eval in Cursor, Gemini CLI or GitHub Copilot?

Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add affaan-m/ECC --skill agent-eval -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/agent-eval, .gemini/skills/agent-eval, .github/skills/agent-eval and .opencode/skills/agent-eval in your project.

What does Agent Eval need to run?

SKILL.md names no scripts, command-line tools or credentials: Agent Eval is instructions for the agent only. Our summary lists: Docker.

Does Agent Eval access the network?

SKILL.md names 1 domain. As links in the text: github.com. This is read from the text; nothing was executed.

Is Agent Eval safe to install?

Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.

What licence does Agent Eval use?

Agent Eval is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Agent Eval use?

About 786 tokens (SKILL.md is roughly 3.1k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.

What are the alternatives to Agent Eval?

Skills that share tags, products or a category with Agent Eval: Finishing a Development Branch (obra/superpowers, 297k stars), Code Review Checklist (shareAI-lab/learn-claude-code, 78k stars), Code Design Rationale Investigator (cursor/plugins, 10k stars) and Contributor-First PR Merge (HKUDS/OpenHarness, 16k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Agent Eval?

affaan-m (a GitHub user) maintains it in affaan-m/ECC, which has 275,546 GitHub stars. The repository holds 673 skills in this directory. The repository was last updated on October 5, 2026.

Source: affaan-m/ECC on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.