Parse Package JSON

Parse Package JSON

Extract structured data from package.json files for version management, dependency auditing, and metadata retrieval.

When to Use

• Get current project version for release workflows
• Extract dependency list for auditing
• Read package metadata for reports
• Validate package.json structure

Instructions

Step 1: Read package.json

Use Read tool to load package.json file.

Expected Input:

• file_path: Path to package.json (default: ./package.json)

Tools Used: Read

Step 2: Parse JSON

Parse the JSON content and validate structure.

Validation:

• File must be valid JSON
• Must contain name and version fields at minimum
• Dependencies should be objects (if present)

Step 3: Extract Fields

Extract relevant fields into structured output.

Fields to Extract:

• version: Semantic version string
• name: Package name
• description: Package description (optional)
• dependencies: Production dependencies object (optional)
• devDependencies: Development dependencies object (optional)
• scripts: Available npm scripts (optional)
• main: Entry point file (optional)
• private: Private flag (optional)

Step 4: Return Structured Data

Return extracted data as JSON object.

Expected Output:

{
  "version": "0.7.0",
  "name": "megacampus2",
  "description": "Project description",
  "dependencies": {
    "react": "^18.2.0"
  },
  "devDependencies": {
    "typescript": "^5.0.0"
  },
  "scripts": {
    "build": "tsc",
    "test": "jest"
  },
  "main": "dist/index.js",
  "private": true
}

Error Handling

• File Not Found: Return error with message "package.json not found at {path}"
• Invalid JSON: Return error with parsing details
• Missing Required Fields: Return error listing missing fields (name, version)
• Invalid Structure: Return error describing structure issue

Examples

Example 1: Extract Version

Input:

file_path: ./package.json

Output:

{
  "version": "0.7.0",
  "name": "megacampus2"
}

Example 2: Full Package Info

Input:

file_path: ./packages/client/package.json

Output:

{
  "version": "1.2.3",
  "name": "@megacampus/client",
  "dependencies": {
    "react": "^18.2.0",
    "react-dom": "^18.2.0"
  },
  "scripts": {
    "dev": "vite",
    "build": "vite build"
  }
}

Example 3: Error - File Not Found

Input:

file_path: ./nonexistent.json

Output:

{
  "error": "package.json not found at ./nonexistent.json",
  "success": false
}

Validation

• Can read package.json from default path
• Can read package.json from custom path
• Extracts all specified fields correctly
• Handles missing optional fields gracefully
• Returns error for missing file
• Returns error for invalid JSON
• Returns error for missing required fields

Supporting Files

• schema.json: JSON schema defining expected package.json structure