siege

siege is a skill for Claude Code, Codex from simota/agent-skills. It costs 34 tokens per session (5,584 once invoked), scanned A, original, MIT.

A system-resilience testing skill for checking how software behaves under heavy load, broken dependencies, unexpected failures, or deliberately altered code. It covers load, contract, chaos, and mutation testing.

In plain words
What is it for?
Designing and reviewing tests for performance limits, service contracts, failure recovery, fault injection, and whether the test suite detects intentional code changes.
Why use it?
Normal tests may not reveal capacity limits or failures between connected services. These checks provide evidence about reliability before real users discover the weaknesses.

Skill for Claude CodeCodex

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

Good fit Designing and reviewing tests for performance limits, service contracts, failure recovery, fault injection, and whether the test suite detects intentional code changes.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/simota/agent-skills/siege
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 simota/agent-skills --skill siege
Clone the repo
git clone --depth 1 https://github.com/simota/agent-skills

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 siege

README.md
[![agentmods](https://agentmods.dev/badge/skills/simota/agent-skills/siege/github.svg)](https://agentmods.dev/skills/simota/agent-skills/siege)
Your own site
<a href="https://agentmods.dev/skills/simota/agent-skills/siege"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/siege/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 siege

Your own site · 80×15
<a href="https://agentmods.dev/skills/simota/agent-skills/siege"><img src="https://agentmods.dev/badge/skills/simota/agent-skills/siege.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 34 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,584 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. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
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 Excessive Agency · line 96
    Skill enables autonomous high-impact decisions without human-in-the-loop verification. Critical operations (destructive commands, financial transactions, data deletion) should require explicit user confirmation.
    Fix: Add human-in-the-loop confirmation for destructive, irreversible, or high-impact operations. Never auto-execute commands that modify files, send data, or alter system state.
  • low Excessive Agency · line 137
    Skill's behavior or capabilities extend beyond its stated purpose. Scope creep allows an agent to perform actions unrelated to its documented functionality, increasing the attack surface.
    Fix: Limit the skill's scope to its documented purpose. Remove instructions that enable the agent to perform actions outside its stated functionality.
How audits are shown
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 $0.00034 $0.05584
Opus 5 $0.00017 $0.02792
Sonnet 5 $0.00007 $0.01117
Haiku 4.5 $0.00003 $0.00558

Measured 6d ago against content hash 8b86cfc21b49, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

siege 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.

siege/SKILL.md · 309 lines

How it starts

The opening of the file, as written. The whole thing — 309 lines — stays where its author put it; the contents beside it link to each section on GitHub.

siege

Siege verifies system limits before users find them. It designs and audits load tests, contract tests, chaos experiments, mutation tests, and resilience checks. It reports evidence and recommended follow-up work; implementation fixes belong to partner agents.

Read the full file on GitHub · 309 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. 6d ago First seen · 309 lines · 34 tokens per session scan A 8b86cfc21b49

Subscribe to this mod's changes

siege is a skill published in the GitHub repository simota/agent-skills (76 stars, last pushed 7d ago), licensed MIT. It adds 34 tokens to every session and 5,584 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.