js-analysis

Extracts complete API request signatures, credentials, and SPA routes from JavaScript files.

2|1|Updated Aug 28, 2026
One-click install
npx skills add https://github.com/lycheer1126/xs-bigdan --skill js-analysis-lycheer1126
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: js-analysis
Source: https://github.com/lycheer1126/xs-bigdan/tree/main/knowledge/skills/js_analysis
Command: npx skills add https://github.com/lycheer1126/xs-bigdan --skill js-analysis-lycheer1126

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve? During authorized security testing, manually reviewing every JavaScript file on a target site is slow and error-prone, and missing hidden API endpoints, hardcoded credentials, or admin routes means missing vulnerabilities. This Skill enforces a disciplined, full-coverage workflow for collecting and deeply analyzing all JS files so no endpoint or secret is overlooked. ## Core Features & Use Cases - Dual-channel JS collection: Combines automated crawler output with wayback machine URLs, HTML script tag extraction, and manual saves, then organizes files locally by domain. - Complete request signature extraction: For every fetch, axios, $.ajax, XMLHttpRequest, and GraphQL call, it captures method, URL, Content-Type, required/optional parameters, and authentication requirements into a structured _endpoint_params.json mapping table. - Secret, route, and interceptor mining: Extracts hardcoded API keys, JWT secrets, AES keys/IVs, SPA hash routes (Vue/React Router), and axios request interceptor logic that auto-injects tokens and signatures. - Use Case: While testing an authorized SPA target, run this workflow to download all JS chunks (including lazy-loaded admin bundles), extract 30+ API endpoints with parameter requirements, and hand the mapping table to downstream fuzzing and crypto-attack stages. ## Quick Start Ask the agent to perform full JS collection and deep analysis on the authorized target domain and produce the _endpoint_params.json endpoint-to-parameter mapping table.

Frequently Asked Questions about js-analysis

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I extract API endpoints from JavaScript files?

Download all JS files locally, then read each file completely to find fetch, axios, $.ajax, and GraphQL calls. For each call, record the HTTP method, URL, Content-Type, parameter names, and auth requirements into a structured endpoint mapping table.

How to find hardcoded API keys and secrets in JavaScript?

Search for assignment patterns like accessKeyId, JWT_SECRET, CryptoJS key/IV parsing, and OAuth client secrets, then read the full surrounding code. Cloud keys often start with prefixes like AKID, LTAI, AKIA, or AIza.

Why analyze lazy-loaded chunk JS files during reconnaissance?

Lazy-loaded chunk files frequently contain admin interfaces and hidden API endpoints not referenced in the main app bundle. Skipping them means missing high-value attack surface such as /admin/* routes and management APIs.

What is a request signature in JS endpoint analysis?

A request signature is the complete specification of an API call: HTTP method, full URL, Content-Type, required and optional parameters, and authentication mechanism. Extracting only URLs without parameters leaves fuzzing stages without enough information to build valid requests.

When should JavaScript files be skipped during analysis?

Only confirmed third-party libraries like moment.js or lodash can be skipped, and each skip must be recorded with a reason in the tracking metadata. Any file containing application, admin, or interceptor logic must be fully read.