spec-stress-test

spec-stress-test is a skill for Claude Code, Codex from Waddling-Penguin/mogkit. It costs 4 tokens per session (1,110 once invoked), scanned A, original, MIT.

A risk review for a product requirements document, or PRD, which describes what a product should do. It lists edge cases, failures, conflicting requirements, hidden assumptions, and the user impact of problems, ranked by severity.

In plain words
What is it for?
Use it to challenge a PRD or technical specification before implementation, especially for unusual inputs, unreliable systems, and conflicting rules.
Why use it?
It exposes weaknesses that are easy to miss when a specification is read only through its intended happy path.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to challenge a PRD or technical specification before implementation, especially for unusual inputs, unreliable systems, and conflicting rules.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/waddling-penguin/mogkit/spec-stress-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 Waddling-Penguin/mogkit --skill spec-stress-test
Clone the repo
git clone --depth 1 https://github.com/Waddling-Penguin/mogkit

Made for: Claude Code, 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 spec-stress-test

README.md
[![agentmods](https://agentmods.dev/badge/skills/waddling-penguin/mogkit/spec-stress-test/github.svg)](https://agentmods.dev/skills/waddling-penguin/mogkit/spec-stress-test)
Your own site
<a href="https://agentmods.dev/skills/waddling-penguin/mogkit/spec-stress-test"><img src="https://agentmods.dev/badge/skills/waddling-penguin/mogkit/spec-stress-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 spec-stress-test

Your own site · 80×15
<a href="https://agentmods.dev/skills/waddling-penguin/mogkit/spec-stress-test"><img src="https://agentmods.dev/badge/skills/waddling-penguin/mogkit/spec-stress-test.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 4 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,110 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 $0.00004 $0.01110
Opus 5 $0.00002 $0.00555
Sonnet 5 $0.00001 $0.00222
Haiku 4.5 $0.00000 $0.00111

Measured 10d ago against content hash 360ec46e0593, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

spec-stress-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 10d 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.

skills/standalone/spec-stress-test/SKILL.md · 101 lines

How it starts

The opening of the file, as written. The whole thing — 101 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Purpose

A spec read by its author looks airtight. The author has the mental model the words gesture at, so gaps and ambiguities slide past unnoticed. This skill reads the spec as an adversary — looking for what it does not say, where two requirements collide, and where the user will be stranded when reality deviates from the happy path.

It does NOT rewrite the spec. It does not suggest replacement language. It does not produce a "v2 with my fixes." The output is the attack list. The PM decides which attacks deserve a fix and writes the fixes themselves. Rewriting the spec would let the PM skip the work of deciding which problems are real, which are out of scope, and which are acceptable risks.

Procedure

  1. Read the pasted spec end to end.
  2. Identify the implicit happy path the spec assumes. Note it briefly — it is the contrast against which everything else gets examined.
  3. Generate attacks in five categories. For each attack, write one line, in the user's perspective where possible: a. Edge cases — inputs, states, or scales the spec doesn't address (empty state, max state, single-user, ten-million-user, offline, slow network, the third device). b. Failure modes — what breaks when a dependency is unavailable, partial, slow, or wrong. What does the user see? c. Race conditions / requirement collisions — two requirements in the spec that contradict each other, or that work individually but not when both fire at once. d. Unstated assumptions — beliefs the spec relies on without naming. ("Assumes the user has already done X." "Assumes the data is clean.") e. User-visible failure UX — for each failure mode, what does the end-user actually experience? Silent failure, confusing state, lost work, etc.
  4. Rank every attack by severity. Use three levels:
    • Critical — ships broken or unsafe; users lose data, get stuck, or are misled.
    • High — degrades the experience meaningfully for a non-trivial segment.
    • Medium — real but narrow; acceptable to defer with a stated mitigation. Do not pad with low-severity items. If something does not clear "Medium", drop it.
  5. Add a short What the spec doesn't tell me section listing the information you'd need from the PM to sharpen any "unclear" findings above. This is the gap the spec itself has, not your gap.
  6. Emit the output contract. Do not propose replacement spec language.

Read the full file on GitHub · 101 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. 10d ago First seen · 101 lines · 4 tokens per session scan A 360ec46e0593

Subscribe to this mod's changes

spec-stress-test is a skill published in the GitHub repository Waddling-Penguin/mogkit (5 stars, last pushed 3mo ago), licensed MIT. It adds 4 tokens to every session and 1,110 once invoked, about $0.0000 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 2026-08-31.

Related

Other skills, from other repositories

find-skills

Discovers, searches, and installs skills from multiple AI agent skill marketplaces (400K+ skills) using the SkillKit CLI. Supports browsing official partner collections (Anthropic, Vercel, Supabase, Stripe, and more) and community repositories, searching by domain or technology, and installing specific skills from…

rohitg00/skillkit · 162 tokens

find-skills

Helps users discover and install agent skills when they ask questions like "how do I do X", "find a skill for X", "is there a skill that can...", or express interest in extending capabilities. This skill should be used when the user is looking for functionality that might exist as an installable skill.

rexleimo/aios · 67 tokens

opencli-sitemap-author

Use when creating or maintaining OpenCLI site sitemaps: agent-facing navigation, page-state, action, workflow, API-reference, pitfall, and fallback knowledge for a website. Use after browser exploration discovers durable site context, when a sitemap is stale, or when promoting local site knowledge into the repo.

jackwener/OpenCLI · 67 tokens

feishu

Work with Feishu or Lark bots, docs, sheets, bitables, approval flows, and OpenAPI/MCP setup without hardcoding credentials.

Hmbown/CodeWhale · 33 tokens

interview

Ask one useful structured question at a time only when material product/implementation choices are genuinely missing; remember answers and produce a brief/spec. Discoverable facts should be investigated instead of asked.

Hmbown/CodeWhale · 40 tokens

recipe-create-meet-space

Create a Google Meet meeting space and share the join link.

googleworkspace/cli · 18 tokens