Framework Detector Skill

Quick Reference

When to Use: Automatically detect framework in project before loading framework-specific skills

Supported Frameworks: NestJS, React, Phoenix, Rails, .NET/ASP.NET Core, Blazor

Detection Method: Multi-signal analysis with weighted confidence scoring

Usage

Basic Detection

const FrameworkDetector = require('./detect-framework');

const detector = new FrameworkDetector('/path/to/project');
const result = await detector.detect();

console.log(result.primary);    // "nestjs"
console.log(result.confidence); // 0.92
console.log(result.alternates); // [{ framework: "dotnet", confidence: 0.45 }]

CLI Usage

# Detect framework in current directory
./detect-framework.js

# Detect framework in specific project
./detect-framework.js /path/to/project

# Output format (JSON)
{
  "primary": "react",
  "confidence": 0.89,
  "alternates": [],
  "details": { ... }
}

Detection Signals

1. Package Manager (Weight: 10)

• Node.js: package.json dependencies
• Ruby: Gemfile gems
• Elixir: mix.exs dependencies
• .NET: *.csproj PackageReferences

2. Files (Weight: 8-9)

• Required: Framework-specific config files
• Optional: Common project structure files
• Wildcards: Pattern matching (e.g., *.csproj)

3. Imports (Weight: 7-8)

• Code pattern analysis in source files
• Regex-based matching
• File sampling for performance (max 20 files)

4. Boost Factors (Multiplier: 1.2-1.6x)

• Strong indicators multiply confidence
• Framework-specific patterns
• Examples:
  • NestJS: nest-cli.json (+50%)
  • React: JSX files (+40%)
  • Blazor: .razor files (+60%)

Confidence Threshold

Default: 0.8 (80% confidence required)

Interpretation:

• ≥ 0.9: Very high confidence
• 0.8-0.9: High confidence
• 0.6-0.8: Medium confidence (below threshold)
• < 0.6: Low confidence

Framework-Specific Patterns

NestJS Detection

✓ @nestjs/core in package.json
✓ nest-cli.json exists
✓ @Module decorator in .ts files
✓ @Controller decorator in .ts files

React Detection

✓ react in package.json
✓ .jsx or .tsx files exist
✓ useState or useEffect in code
✓ createRoot in code

Phoenix Detection

✓ {:phoenix, in mix.exs
✓ config/config.exs exists
✓ Phoenix.Endpoint in .ex files
✓ Phoenix.Router in .ex files

Rails Detection

✓ gem 'rails' in Gemfile
✓ config/application.rb exists
✓ Rails.application in code
✓ ActiveRecord::Base in code

.NET Detection

✓ Microsoft.AspNetCore in .csproj
✓ Program.cs exists
✓ [ApiController] in .cs files
✓ using Microsoft.AspNetCore

Blazor Detection

✓ Microsoft.AspNetCore.Components in .csproj
✓ .razor files exist
✓ @page directive in .razor files
✓ ComponentBase in code

Performance

Optimizations:

• File sampling (10-20 files max per check)
• Glob ignore patterns (node_modules, dist, build)
• Early exit on strong matches
• Async/await for parallel checks

Typical Detection Time: 100-500ms

Error Handling

No Frameworks Detected:

{
  primary: null,
  confidence: 0,
  alternates: [],
  details: {}
}

Multiple Frameworks (e.g., monorepo):

{
  primary: "react",
  confidence: 0.91,
  alternates: [
    { framework: "nestjs", confidence: 0.87 }
  ]
}

Integration with SkillLoader

const { SkillLoader } = require('../skill-loader');
const FrameworkDetector = require('./detect-framework');

async function loadFrameworkSkill(projectRoot) {
  // 1. Detect framework
  const detector = new FrameworkDetector(projectRoot);
  const result = await detector.detect();

  // 2. Handle low confidence
  if (result.confidence < 0.8) {
    // Prompt user or use alternates
    console.warn('Low confidence detection');
  }

  // 3. Load skill
  const loader = new SkillLoader({
    agentName: 'backend-developer',
    agentVersion: '3.0.0'
  });

  const skill = await loader.loadSkill(result.primary, 'quick');
  return skill;
}

Configuration

Edit framework-patterns.json to:

• Add new frameworks
• Adjust detection weights
• Modify confidence threshold
• Update boost factors

See Also

• framework-patterns.json – Detection patterns configuration
• detect-framework.js – Implementation source
• ../../lib/skill-loader.js – Skill loading integration