counterexample-generation

counterexample-generation is a skill for Claude Code, Codex from yogsoth-ai/stress-test. It costs 22 tokens per session (157 once invoked), scanned A, original, Apache-2.0.

A systematic method for producing counterexamples to a claim. It searches boundary cases, degenerate cases, and cases suggested by the subject area.

In plain words
What is it for?
Use it to challenge a theorem, hypothesis, rule, or general statement before accepting it.
Why use it?
It reduces reliance on one obvious test case and makes it easier to expose claims that fail outside their usual examples.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions subagents.

Good fit Use it to challenge a theorem, hypothesis, rule, or general statement before…

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/yogsoth-ai/stress-test/counterexample-generation
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 yogsoth-ai/stress-test --skill counterexample-generation
Clone the repo
git clone --depth 1 https://github.com/yogsoth-ai/stress-test

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 counterexample-generation

README.md
[![agentmods](https://agentmods.dev/badge/skills/yogsoth-ai/stress-test/counterexample-generation.svg)](https://agentmods.dev/skills/yogsoth-ai/stress-test/counterexample-generation)
Your own site
<a href="https://agentmods.dev/skills/yogsoth-ai/stress-test/counterexample-generation"><img src="https://agentmods.dev/badge/skills/yogsoth-ai/stress-test/counterexample-generation.svg" alt="Measured on agentmods" height="20"></a>
Per session 22 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 157 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 $0.00022 $0.00157
Opus 5 $0.00011 $0.00078
Sonnet 5 $0.00004 $0.00031
Haiku 4.5 $0.00002 $0.00016

Measured 6d ago against content hash 698c838764a9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

counterexample-generation 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 6d 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/counterexample-generation/SKILL.md · 27 lines

What it actually says

Counterexample Generation

Subagent that produces counterexamples to a claim using boundary cases, degenerate cases, and domain-specific heuristics.

Available SOPs

Optional, no fixed order; the final leaf is always a sop.

SOP When to use
spawn-agent Spawn a customized CC subagent with full MCP tool access. Used by SOPs that declare execution: subagent.
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. 6d ago First seen · 27 lines · 22 tokens per session scan A 698c838764a9

Subscribe to this mod's changes

counterexample-generation is a skill published in the GitHub repository yogsoth-ai/stress-test (2 stars, last pushed 2mo ago), licensed Apache-2.0. It adds 22 tokens to every session and 157 once invoked, about $0.0001 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.

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