skill-test

skill-test is a skill for Codex from frabcd/codex-ai-game-studio. It costs 31 tokens per session (526 once invoked), scanned A, original, MIT.

A read-only checker for coding-agent skill files that tests their required structure and expected behaviour. It has static, specification, and audit modes for different levels of review.

In plain words
What is it for?
Validating a skill package, checking its documentation and configuration, and producing a coverage report.
Why use it?
It catches invalid metadata, broken links, unsafe instructions, secrets, unsupported settings, and missing coverage before a skill is used.

Skill for Codex

Written for Codex: agents/openai.yaml present. Also seen: mentions subagents; mentions Codex.

Good fit Validating a skill package, checking its documentation and configuration, and producing a coverage report.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/frabcd/codex-ai-game-studio/skill-test
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 frabcd/codex-ai-game-studio --skill skill-test
Clone the repo
git clone --depth 1 https://github.com/frabcd/codex-ai-game-studio

Made for: Codex.

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 skill-test

README.md
[![agentmods](https://agentmods.dev/badge/skills/frabcd/codex-ai-game-studio/skill-test/github.svg)](https://agentmods.dev/skills/frabcd/codex-ai-game-studio/skill-test)
Your own site
<a href="https://agentmods.dev/skills/frabcd/codex-ai-game-studio/skill-test"><img src="https://agentmods.dev/badge/skills/frabcd/codex-ai-game-studio/skill-test/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 skill-test

Your own site · 80×15
<a href="https://agentmods.dev/skills/frabcd/codex-ai-game-studio/skill-test"><img src="https://agentmods.dev/badge/skills/frabcd/codex-ai-game-studio/skill-test.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 31 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 526 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.
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 $0.00031 $0.00526
Opus 5 $0.00015 $0.00263
Sonnet 5 $0.00006 $0.00105
Haiku 4.5 $0.00003 $0.00053

Measured 7d ago against content hash 159b23706147, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

skill-test 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 7d 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.

plugins/ai-game-studio/skills/skill-test/SKILL.md · 50 lines

How it starts

The opening of the file, as written. The whole thing — 50 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Port provenance: adapted from the pinned upstream source at 984023ddac0d5e27624f2baacde6105e45de375f under MIT; see the repository parity ledger for the exact path and blob.

Test a Codex skill

Evaluate a target skill as both a package and a behavior. Testing is read-only unless the user separately approves writing a report.

Static validation

  1. Locate the skill directory and read SKILL.md plus agents/openai.yaml.
  2. Require YAML frontmatter containing exactly name and description.
  3. Confirm the directory name and frontmatter name match and use lowercase hyphen-case.
  4. Confirm the description explains both what the skill does and when it should activate. Reject unsupported legacy frontmatter and broken relative links.
  5. Confirm agents/openai.yaml has a useful display name, a 25-64 character short description, and a default prompt that explicitly names the skill.
  6. Confirm mutating setup, installation, engine-control, catalog-refresh, and destructive enhancement workflows disable implicit invocation.
  7. Scan for secrets, absolute developer paths, path escapes, unsupported model pins, product-specific tool declarations, and platform-only assumptions.

Run the official skill validator when it is available. Report the exact command, exit status, and diagnostics.

Forward testing

Use isolated Codex subagents with the raw skill instructions. Cover:

  • a direct explicit invocation;
  • a natural-language request that should select the skill when implicit use is enabled;
  • a near-miss that should route elsewhere;
  • a negative or unsafe request that must preserve approval and rights gates.

Do not reveal an expected answer in the test prompt. Score routing, instruction adherence, safety boundary, artifact clarity, platform neutrality, and evidence. For failures, distinguish instruction defects from missing external capabilities.

Return a concise test matrix and a prioritized improvement proposal. Do not edit the tested skill until the user approves that separate change.

Read the full file on GitHub · 50 lines

Files

What ships with it

1 file 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. 7d ago First seen · 50 lines · 31 tokens per session scan A 159b23706147

Subscribe to this mod's changes

skill-test is a skill published in the GitHub repository frabcd/codex-ai-game-studio (10 stars, last pushed 3d ago), licensed MIT. It adds 31 tokens to every session and 526 once invoked, about $0.0002 per session on Opus 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 2026-09-03.

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