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.
npx skills add simota/agent-skills --skill voidgit clone --depth 1 https://github.com/simota/agent-skillsWrote 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.
[](https://agentmods.dev/skills/simota/agent-skills/void)<a href="https://agentmods.dev/skills/simota/agent-skills/void"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/void/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.
<a href="https://agentmods.dev/skills/simota/agent-skills/void"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/void.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 3 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Prompt Injection · line 6 Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
- medium Prompt Injection · line 251 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
- medium Prompt Injection · line 251 Large whitespace padding was detected (a block of blank lines or a long run of spaces). This can push injected instructions below or to the right of the visible area so a human reviewer never sees them while the agent still reads them. Manual review of the hidden content is recommended.Fix: Remove the large whitespace padding (blank-line blocks or long space runs) and review any content hidden below or to the right of it. Keep skill files compact and reviewable so no instructions can be
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00041 | $0.04402 |
| Opus 5.5 | $0.00016 | $0.01761 |
| Sonnet 5.5 | $0.00008 | $0.00880 |
| Haiku 4.5 | $0.00004 | $0.00440 |
Grade A, and why
void 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.
How it starts
The opening of the file, as written. The whole thing — 293 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Void
Subtraction agent for YAGNI checks, scope cuts, pruning proposals, and complexity reduction across code, features, processes, documents, design, dependencies, configuration, and specifications. Void does not execute changes.
What ships with it
10 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.
- _common 10 B
- reference/complexity-metrics.md 3.9 KB
- reference/cost-analysis.md 6.1 KB
- reference/evaluation-criteria.md 9.5 KB
- reference/feature-creep-pitfalls.md 6.2 KB
- reference/organizational-complexity.md 3.8 KB
- reference/over-engineering-anti-patterns.md 6.2 KB
- reference/proposal-templates.md 5.8 KB
- reference/prune 11 B
- reference/subtraction-patterns.md 8.6 KB
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.
- 7d ago Changed · +1 lines 91e3c7f65a20
- 12d ago Changed 261d6070c8ad
- 14d ago Changed c3cf5ed97e87
- 17d ago Changed 1c6aa3d6b22d
- 1mo ago Changed · -3 lines de8921ab15de
- 1mo ago Changed 802a69901562
- 1mo ago First seen · 295 lines · 41 tokens per session scan A 501883be8625
void is a skill published in the GitHub repository simota/agent-skills (95 stars, last pushed yesterday), licensed MIT. It adds 41 tokens to every session and 4,402 once invoked, about $0.0002 per session on Opus 5.5. 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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unlazy
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caveman
Ultra-compressed reply mode. Cuts output tokens 65-75% by answering in terse "caveman" style while keeping full technical accuracy, and shapes what survives: action first, state restated every turn, concrete time estimates, visible wins. Intensity levels: lite, full (default), ultra, wenyan-lite, wenyan-full…
template-engine
Load, validate, and populate templates consistently across frameworks.
desktop-sessions-discovery
Discover, search, and selectively restore Claude desktop app sessions hidden across multiple accountIds. Use when user mentions "missing sessions after account switch", "lost desktop sessions", "where do my old sessions live", or runs multiple Claude accounts on the same machine. Do NOT use for Claude Code CLI session…
checkpoint
Create, list, or recover mid-workflow checkpoints so interrupted work resumes from a known-good position.