Library Detection Skill

Automatically detect the technology stack of a project by analyzing package manifests and configuration files. Returns structured data for use in onboarding, documentation discovery, and tool configuration.

Variables

Variable	Default	Description
SCAN_DEPTH	3	Max directory depth to search for manifests
INCLUDE_DEV_DEPS	true	Include development dependencies in analysis
DETECT_FRAMEWORKS	true	Identify frameworks from dependencies
DETECT_TEST_TOOLS	true	Identify test frameworks and runners
OUTPUT_FORMAT	json	Output format: json, markdown, or toon

Instructions

MANDATORY - Follow the Workflow steps below in order. Do not skip steps.

1. Scan for package manifests in the project
2. Parse each manifest to extract dependencies
3. Classify dependencies into categories
4. Detect frameworks and test tools from dependency patterns
5. Output structured stack summary

Red Flags - STOP and Reconsider

If you're about to:

• Assume a framework without checking imports or config files
• Skip manifest files because "the project is simple"
• Hardcode framework versions instead of reading from manifests
• Report a library without verifying it's actually used

STOP -> Read the manifest files -> Verify with imports/configs -> Then report

Workflow

1. Discover Manifests

Scan for these files (in order of priority):

File	Language	Parser
package.json	JavaScript/TypeScript	JSON
pyproject.toml	Python	TOML
requirements.txt	Python	Line-based
go.mod	Go	Go mod
Cargo.toml	Rust	TOML
pubspec.yaml	Dart/Flutter	YAML
CMakeLists.txt	C/C++	CMake
meson.build	C/C++	Meson
WORKSPACE	Bazel	Bazel
pom.xml	Java	XML
build.gradle	Java/Kotlin	Gradle DSL
Gemfile	Ruby	Ruby DSL
composer.json	PHP	JSON

Also check for:

• Dockerfile - containerization
• docker-compose.yml - container orchestration
• .github/workflows/*.yml - CI/CD
• Makefile - build system
• tsconfig.json - TypeScript config
• vite.config.* / webpack.config.* - bundlers

2. Parse Dependencies

For each manifest, extract:

• Production dependencies: runtime requirements
• Development dependencies: build/test tools
• Peer dependencies: expected host environment
• Optional dependencies: feature flags

3. Classify Stack

Group findings into:

{
  "languages": ["typescript", "python", "go", "rust", "dart", "cpp"],
  "frameworks": [
    {"name": "react", "version": "^18.0.0", "category": "frontend"},
    {"name": "fastapi", "version": "^0.100.0", "category": "backend"}
  ],
  "test_frameworks": [
    {"name": "vitest", "version": "^1.0.0"},
    {"name": "pytest", "version": "^7.0.0"}
  ],
  "build_tools": ["vite", "uv", "docker"],
  "databases": ["postgresql", "redis"],
  "cloud_providers": ["aws", "vercel"],
  "ci_cd": ["github-actions"]
}

4. Framework Detection Patterns

Use the cookbook for specific detection logic:

• Read ./cookbook/manifest-parsing.md for parsing rules
• Match dependency names against known framework patterns

5. Output

Return the structured stack summary in the requested format.

Cookbook

Manifest Parsing

• IF: Parsing any package manifest
• THEN: Read and execute ./cookbook/manifest-parsing.md

Quick Reference

Detection Patterns

Dependency Pattern	Detected As
react, react-dom	React framework
vue, @vue/*	Vue framework
next	Next.js framework
fastapi	FastAPI framework
django	Django framework
flask	Flask framework
express	Express.js framework
vitest, jest	JavaScript test framework
pytest	Python test framework
gtest, gmock, catch2	C/C++ test framework
flutter, flutter_test	Flutter framework
@testing-library/*	Testing utilities

Category Mappings

Category	Examples
frontend	react, vue, svelte, angular
backend	fastapi, django, express, gin
database	prisma, sqlalchemy, typeorm
testing	vitest, jest, pytest, playwright
build	vite, webpack, esbuild, rollup
linting	eslint, prettier, ruff, black
typing	typescript, mypy, pyright
build-native	cmake, meson, bazel

Output Schema

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "type": "object",
  "properties": {
    "project_root": {"type": "string"},
    "scanned_at": {"type": "string", "format": "date-time"},
    "languages": {
      "type": "array",
      "items": {"type": "string"}
    },
    "frameworks": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "name": {"type": "string"},
          "version": {"type": "string"},
          "category": {"type": "string"}
        }
      }
    },
    "test_frameworks": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "name": {"type": "string"},
          "version": {"type": "string"}
        }
      }
    },
    "build_tools": {
      "type": "array",
      "items": {"type": "string"}
    },
    "databases": {
      "type": "array",
      "items": {"type": "string"}
    },
    "cloud_providers": {
      "type": "array",
      "items": {"type": "string"}
    },
    "ci_cd": {
      "type": "array",
      "items": {"type": "string"}
    },
    "manifests_found": {
      "type": "array",
      "items": {"type": "string"}
    }
  }
}

Integration

Other skills and commands can use this skill for:

1. Documentation discovery: Map detected frameworks to doc sources
2. Onboarding: Generate quickstart guides tailored to the stack
3. Tool configuration: Auto-configure linters, formatters, test runners
4. Agent routing: Select appropriate AI providers based on stack

Example usage in another skill:

## Prerequisites

Before implementing, run the `library-detection` skill to identify:
- Test frameworks (for writing tests)
- Build tools (for verification)
- Database libraries (for data layer work)