stress-test

stress-test is a skill for Claude Code from v0idOS/performance-deity. It costs 34 tokens per session (343 once invoked), scanned A, original, MIT.

A skill for stress-testing software with extreme inputs, malformed data, and simulated network or database failures.

In plain words
What is it for?
Use it to fuzz functions with oversized, null, invalid, deeply nested, or malformed inputs, document each failure, and add validation, pagination, streaming, retries, or circuit breakers.
Why use it?
It helps uncover crashes, memory exhaustion, infinite loops, and incorrect responses at the boundaries where untrusted or unusual data enters the system.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the performance-deity plugin — 17 skills shipped together

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.

agentmods
npx agentmods add skills/v0idos/performance-deity/stress-test
Any agent
npx skills add v0idOS/performance-deity --skill stress-test
Clone the repo
git clone --depth 1 https://github.com/v0idOS/performance-deity

Made for: Claude Code.

Or install performance-deity, the plugin that ships this one along with the rest of its 17 skills.

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 stress-test

README.md
[![agentmods](https://agentmods.dev/badge/skills/v0idos/performance-deity/stress-test.svg)](https://agentmods.dev/skills/v0idos/performance-deity/stress-test)
Your own site
<a href="https://agentmods.dev/skills/v0idos/performance-deity/stress-test"><img src="https://agentmods.dev/badge/skills/v0idos/performance-deity/stress-test.svg" alt="Measured on agentmods" 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 343 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00343
Opus 5 $0.00017 $0.00171
Sonnet 5 $0.00007 $0.00069
Haiku 4.5 $0.00003 $0.00034

Measured 5d ago against content hash c9c780ff8643, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

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 5d 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/stress-test/SKILL.md · 40 lines

What it actually says

Execute all four phases in order.

Phase 1 — Fuzzer

Write a script that sends the following inputs to the target function:

  • 1GB string payloads
  • null, undefined, NaN, -1, Infinity
  • Deeply nested recursive JSON (depth >1,000)
  • Malformed Unicode strings (\uFFFD, null bytes, RTL override characters)
  • Simulated network drops or database timeouts via mocked I/O

Phase 2 — Attack

Run the fuzzer. For each failure, document:

  • The exact input that caused the failure
  • The failure mode: unhandled exception, memory exhaustion, infinite loop, or incorrect output without error

Phase 3 — Hardening

For every documented failure:

  1. Add input validation at the function boundary. Reject invalid input immediately with a typed error.
  2. Add pagination or streaming for inputs that exceed a byte threshold.
  3. Add a circuit breaker or retry-with-exponential-backoff for every network and database dependency.

Phase 4 — Report

Re-run the full fuzzer. For every input that previously caused a crash, show the new response.

Input Before After
1GB string Crash / OOM 400 Bad Request
Null input Unhandled exception Typed error returned
Nested JSON 1k deep Stack overflow Rejected at boundary

Zero crashes is the target.

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. 5d ago First seen · 40 lines · 34 tokens per session scan A c9c780ff8643

Subscribe to this mod's changes

stress-test is a skill published in the GitHub repository v0idOS/performance-deity (2 stars, last pushed 4mo ago), licensed MIT. It adds 34 tokens to every session and 343 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 2026-08-31.