evaluation

evaluation is a skill for Claude Code, Codex from guanyang/open-agent-hub. It costs 40 tokens per session (3,152 once invoked), scanned A, a copy of evaluation, MIT.

A guide for measuring whether an AI agent system works well over time. It covers repeatable checks, test suites, scoring rules, quality gates, and comparisons with earlier versions.

In plain words
What is it for?
Testing agent pipelines, comparing configurations, checking context changes, catching regressions before release, and monitoring results in production.
Why use it?
AI agents can make different decisions on different runs, so ordinary software tests may miss regressions or give an incomplete picture of quality.

Skill for Claude CodeCodex

Part of the open-agent-hub plugin — 102 skills, 3 commands, 8 agents, 6 MCP servers shipped together

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.

agentmods
npx agentmods add skills/guanyang/open-agent-hub/evaluation
Any agent
npx skills add guanyang/open-agent-hub --skill evaluation
Clone the repo
git clone --depth 1 https://github.com/guanyang/open-agent-hub

Made for: Claude Code, Codex.

Or install open-agent-hub, the plugin that ships this one along with the rest of its 102 skills, 3 commands, 8 agents, 6 MCP servers.

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 evaluation

README.md
[![agentmods](https://agentmods.dev/badge/skills/guanyang/open-agent-hub/evaluation.svg)](https://agentmods.dev/skills/guanyang/open-agent-hub/evaluation)
Your own site
<a href="https://agentmods.dev/skills/guanyang/open-agent-hub/evaluation"><img src="https://agentmods.dev/badge/skills/guanyang/open-agent-hub/evaluation.svg" alt="Measured on agentmods" height="20"></a>
Per session 40 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,152 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 $0.00040 $0.03152
Opus 5 $0.00020 $0.01576
Sonnet 5 $0.00008 $0.00630
Haiku 4.5 $0.00004 $0.00315

Measured 5d ago against content hash 1f31cda0910d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

evaluation 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 5d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/evaluator.py), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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.

Origin

This is a copy

100% identical to evaluation — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/evaluation/SKILL.md · 285 lines

How it starts

The opening of the file, as written. The whole thing — 285 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Evaluation Methods for Agent Systems

Evaluate agent systems differently from traditional software because agents make dynamic decisions, are non-deterministic between runs, and often lack single correct answers. Build evaluation frameworks that account for these characteristics, provide actionable feedback, catch regressions, and validate that context engineering choices achieve intended effects.

When to Activate

Activate this skill when:

  • Testing agent performance systematically
  • Validating context engineering choices
  • Measuring improvements over time
  • Catching regressions before deployment
  • Building quality gates for agent pipelines
  • Comparing different agent configurations
  • Evaluating production systems continuously

Do not activate this skill for adjacent work owned by other skills:

  • Designing the LLM judge itself, pairwise comparison, judge calibration, or bias mitigation: advanced-evaluation.
  • Designing autonomous control surfaces, novelty gates, rollback, or PR approval boundaries: harness-engineering.
  • Debugging a specific context failure mode before measuring it: context-degradation.

Core Concepts

Focus evaluation on outcomes rather than execution paths, because agents may find alternative valid routes to goals. Judge whether the agent achieves the right outcome via a reasonable process, not whether it followed a specific sequence of steps.

Use multi-dimensional rubrics instead of single scores because one number hides critical failures in specific dimensions. Capture factual accuracy, completeness, citation accuracy, source quality, and tool efficiency as separate dimensions, then weight them for the use case.

Use model-judged evaluation only after deterministic checks and rubrics are stable. When the work centers on judge prompts, pairwise comparison, calibration, or bias mitigation, switch to Advanced Evaluation.

Run deterministic validation before LLM judgment whenever the artifact has machine-checkable structure. Schema validity, duplicate keys, rubric math, manifest sync, retrieval status, and required evidence paths should fail fast before an evaluator spends tokens or returns a subjective score.

Read the full file on GitHub · 285 lines

Files

What ships with it

2 files 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. 5d ago First seen · 285 lines · 40 tokens per session scan A 1f31cda0910d

Subscribe to this mod's changes

evaluation is a skill published in the GitHub repository guanyang/open-agent-hub (960 stars, last pushed yesterday), licensed MIT. It adds 40 tokens to every session and 3,152 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to evaluation, differing in 0 lines, and is treated as a copy.

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