js-api-extract

js-api-extract is a skill for Claude Code, Codex from wgpsec/AboutSecurity. It costs 99 tokens per session (1,667 once invoked), scanned A, original, no licence file.

A method for reading JavaScript files used by web applications to find hidden API addresses, keys, internal hostnames, and WebSocket endpoints.

In plain words
What is it for?
Inspecting browser JavaScript bundles during the information-gathering stage of an authorized API security test.
Why use it?
It helps reveal server interfaces that ordinary directory scanning may miss, especially in single-page apps built with React, Vue, or Angular.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Inspecting browser JavaScript bundles during the information-gathering stage of an authorized API security test.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/wgpsec/aboutsecurity/js-api-extract
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 wgpsec/AboutSecurity --skill js-api-extract
Clone the repo
git clone --depth 1 https://github.com/wgpsec/AboutSecurity

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 js-api-extract

README.md
[![agentmods](https://agentmods.dev/badge/skills/wgpsec/aboutsecurity/js-api-extract/github.svg)](https://agentmods.dev/skills/wgpsec/aboutsecurity/js-api-extract)
Your own site
<a href="https://agentmods.dev/skills/wgpsec/aboutsecurity/js-api-extract"><img src="https://agentmods.dev/badge/skills/wgpsec/aboutsecurity/js-api-extract/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 js-api-extract

Your own site · 80×15
<a href="https://agentmods.dev/skills/wgpsec/aboutsecurity/js-api-extract"><img src="https://agentmods.dev/badge/skills/wgpsec/aboutsecurity/js-api-extract.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 99 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,667 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin unknown 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 $0.00099 $0.01667
Opus 5 $0.00049 $0.00834
Sonnet 5 $0.00020 $0.00333
Haiku 4.5 $0.00010 $0.00167

Measured 5d ago against content hash 530604e5ff73, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

js-api-extract scanned grade A with 1 finding 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -s "$TARGET" | grep -oE '(src|href)="[^"]*\.js[^"]*"' | sed 's/.*="\(.*\)"/\1/'
skills/recon/js-api-extract/SKILL.md · 128 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

1 file 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.

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 · 128 lines · 99 tokens per session scan A 530604e5ff73

Subscribe to this mod's changes

js-api-extract is a skill published in the GitHub repository wgpsec/AboutSecurity (1,725 stars, last pushed 9d ago), with no licence file. It adds 99 tokens to every session and 1,667 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

Related

Other skills, from other repositories

redteam-cors-miscfg-detail-pack

Domain routing and boundary guidance for authorized CORS misconfiguration testing, including reflected origins, null origins, subdomain trust, and credential exposure. Use when a task belongs to the CORS testing domain and needs scope, evidence, pivot, or exit criteria.

Netw0rkNoob/VulnClaw · 61 tokens

homepage-generator

Generate a fact-checked academic personal homepage from a CV, optionally augmented by an existing manual homepage and an assets directory. Produces editable structured source files (profile.yml + publications.bib + bio.md + news.md) and a single-file HTML page. Uses Codex MCP for independent factual review against…

wanshuiyin/ARIS-in-AI-Offer · 129 tokens

re-wasm

A workflow for examining WebAssembly modules, the compact binary programs that can run in web pages, browser extensions, games, and other hosts.

dslsdzc/rev-skills · 36 tokens

xss-dom

Guide DOM-based XSS exploitation during authorized penetration testing.

blacklanternsecurity/red-run · 15 tokens

js-reverse

A guide for investigating JavaScript that runs in a web page, including its request-signing logic, runtime values, and connections to browser APIs. It combines source inspection with observing the page while it operates.

Asaiuta/reverse-workbench-skill · 84 tokens

competition-bundle-sourcemap-recovery

Internal downstream skill for ctf-sandbox-orchestrator. CTF-sandbox workflow for source maps, build manifests, chunk registries, emitted bundles, obfuscated loader flow, and frontend runtime recovery. Use when the user asks to reconstruct served JavaScript structure, inspect source maps or chunk maps, trace bundle…

Asaiuta/reverse-workbench-skill · 112 tokens