application-security-testing

A workflow for planning application security testing across an entire product. It helps choose tests for source code, live web applications, APIs, and CI pipelines, then creates a ranked repair plan.

In plain words
What is it for?
Use it to map repositories, services, environments, APIs, credentials, and testing limits before selecting and running security tests.
Why use it?
It prevents teams from running the wrong test or testing everything indiscriminately when a product has several different assets.

Skill for Claude CodeCodex

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/usestrix/strix/application-security-testing
Any agent
npx skills add usestrix/strix --skill application-security-testing
Clone the repo
git clone --depth 1 https://github.com/usestrix/strix

Made for: Claude Code, Codex.

Per session 125 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 953 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 $0.00125 $0.00953
Opus 5 $0.00063 $0.00477
Sonnet 5 $0.00025 $0.00191
Haiku 4.5 $0.00013 $0.00095

Measured 2d ago against content hash 5aad863f88d7, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

application-security-testing 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 2d 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/application-security-testing/SKILL.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Application security testing

Entry point for "make my application secure" requests, where the target is not yet a single URL or repo. The job here is to pick the right test per asset, run it, and produce one ranked plan — not to run everything at maximum depth.

Install, LLM setup, all CLI flags, and the managed-cloud path live in the penetration-testing-with-strix skill. Read it first if strix --version fails.

Only test assets the user owns or is authorized to test. Confirm authorization before the first run, and prefer staging over production, because the agents send real exploit payloads and can change data.

1. Map the assets

Ask (or read from the repo) and write the answers down before scanning:

  • Source — one repo, a monorepo, several services? Which languages/frameworks?
  • Running environments — is there a staging deployment? A public production site? A local dev server only?
  • APIs — REST, GraphQL, gRPC? Is there an OpenAPI/GraphQL schema?
  • Authentication — can you get two test accounts in different tenants? Most high-impact bugs need them.
  • Constraints — out-of-scope paths, whether production may be touched, budget and wall-clock limits.

If there is no staging environment and production is off limits, say so early. A code-only review is still valuable, but it cannot prove exploitability against a live app.

2. Pick the right test per asset

Asset Skill to use
Repository or working tree find-security-vulnerabilities-in-code
Live web app or staging site web-app-penetration-testing
REST/GraphQL/gRPC API api-security-testing
Assessment mapped to OWASP categories owasp-top-10-testing
Every pull request, continuously ci-security-scanning-with-strix
No Docker, no LLM key, or a report an auditor will accept managed-pentesting-with-strix

Those skills carry the flags, credential handling, and result-reading details. Do not duplicate their instructions here.

Read the full file on GitHub · 67 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. 2d ago First seen · 67 lines · 125 tokens per session scan A 5aad863f88d7

Subscribe to this mod's changes

application-security-testing is a skill published in the GitHub repository usestrix/strix (59,426 stars, last pushed 3d ago), licensed Apache-2.0. It adds 125 tokens to every session and 953 once invoked, about $0.0006 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.