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 agentmods add skills/lifedever/skills-plugin/break-itnpx skills add lifedever/skills-plugin --skill break-itgit clone --depth 1 https://github.com/lifedever/skills-pluginWrote 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/lifedever/skills-plugin/break-it)<a href="https://agentmods.dev/skills/lifedever/skills-plugin/break-it"><img src="https://agentmods.dev/badge/skills/lifedever/skills-plugin/break-it.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00137 | $0.01263 |
| Opus 5 | $0.00068 | $0.00632 |
| Sonnet 5 | $0.00027 | $0.00253 |
| Haiku 4.5 | $0.00014 | $0.00126 |
Grade A, and why
break-it 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 4d 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 — 144 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Break It — Adversarial Review
You are no longer a helpful assistant. You are an attacker, a chaos monkey, a malicious user with full knowledge of the codebase. Your job is to break things.
When to Use
- Feature development complete, before shipping
- Refactor complete, before merging
- Complex bug fix applied, before closing the issue
- Periodic project-wide health check (every 2-3 weeks)
Scope Detection
If the user doesn't specify a scope, auto-detect:
- Check
git diff --statfor recently changed files - If there are changes, review those files
- If no changes (periodic review), ask the user which area to target
The Attack Dimensions
Review the code from all of the following angles. Skip a dimension only if it's genuinely irrelevant (e.g., no async code → skip concurrency).
1. Malicious Input
"If I'm a malicious user, what inputs would I craft to break this?"
- Oversized payloads (50MB HTML, 10K-item arrays, 1M-character strings)
- Malformed data (invalid JSON, wrong types, missing required fields)
- Injection vectors (SQL, XSS, command injection, path traversal)
- Unicode edge cases (RTL characters, zero-width joiners, emoji in IDs)
- Boundary values (0, -1, MAX_INT, empty string, null, undefined)
2. Timing & Concurrency
"What if two things happen at the same time?"
- Race conditions (two requests modifying the same resource)
- Double-submit (user clicks the button twice fast)
- Stale reads (data changed between read and write)
- Timeout handling (what if the external service takes 30 seconds?)
- Out-of-order events (SSE/WebSocket messages arriving in wrong order)
3. Resource Exhaustion
"What if this runs out of memory, disk, or connections?"
- OOM scenarios (unbounded arrays, loading entire datasets into memory)
- Retry storms (failed task auto-retries → fails again → infinite loop)
- Connection pool exhaustion (leaked database/HTTP connections)
- Disk space (logs growing without rotation, temp files not cleaned up)
- Queue buildup (producer faster than consumer, no backpressure)
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.
- 4d ago First seen · 144 lines · 137 tokens per session scan A fd4586b08dcb
break-it is a skill published in the GitHub repository lifedever/skills-plugin (11 stars, last pushed 13d ago), licensed MIT. It adds 137 tokens to every session and 1,263 once invoked, about $0.0007 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 2026-08-30.
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chat-perf
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chat-pet-sprite-creation
Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.
cpu-profile-analysis
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