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name: json-validator description: Validate, format, and fix JSON data. Use this skill when working with JSON files, API responses, or configuration files that need validation or formatting.

JSON Validator

Validate, format, and fix JSON data with helpful error messages and suggestions.

When to Use This Skill

Use this skill when you need to:

• Validate JSON syntax and structure
• Format/prettify JSON data
• Fix common JSON errors
• Convert between JSON and other formats
• Analyze JSON structure

Validation

When validating JSON:

1. Check syntax: Identify syntax errors with line numbers
2. Provide context: Show the problematic section
3. Suggest fixes: Offer specific corrections
4. Explain issues: Describe what's wrong and why

Common JSON Errors to Check

• Missing or extra commas
• Unclosed brackets/braces
• Unquoted keys
• Trailing commas (invalid in strict JSON)
• Single quotes instead of double quotes
• Comments (not allowed in JSON)
• Undefined/NaN/Infinity values

Example Validation Output

Copy❌ JSON Validation Failed

Line 5: Trailing comma after last object property
  "name": "example",
  "value": 123,  ← Remove this comma
}

✅ Suggested fix:
{
  "name": "example",
  "value": 123
}

Formatting

When formatting JSON:

1. Use 2-space indentation (standard)
2. Sort keys alphabetically (optional, ask user)
3. Remove unnecessary whitespace
4. Ensure consistent structure

Example

Input (minified):

Copy{"name":"test","items":[1,2,3],"active":true}

Output (formatted):

Copy{
  "name": "test",
  "items": [
    1,
    2,
    3
  ],
  "active": true
}

Fixing Common Issues

Trailing Commas

Copy// ❌ Invalid
{
  "key": "value",
}

// ✅ Fixed
{
  "key": "value"
}

Single Quotes

Copy// ❌ Invalid
{'key': 'value'}

// ✅ Fixed
{"key": "value"}

Unquoted Keys

Copy// ❌ Invalid
{key: "value"}

// ✅ Fixed
{"key": "value"}

Comments

Copy// ❌ Invalid
{
  // This is a comment
  "key": "value"
}

// ✅ Fixed
{
  "key": "value"
}

Conversion

When converting to/from JSON:

From JSON to other formats

• YAML: Preserve structure, use proper indentation
• TOML: Handle nested objects appropriately
• CSV: Flatten structure if needed, handle arrays
• XML: Choose appropriate tag names

To JSON from other formats

• Ensure proper escaping
• Validate the result
• Maintain data types (strings, numbers, booleans, null)

Analysis

When analyzing JSON structure:

1. Report schema:

   • Top-level type (object/array)
   • Key names and types
   • Nesting depth
   • Array sizes

2. Identify patterns:

   • Repeated structures
   • Optional fields
   • Data types used

3. Suggest improvements:

   • Inconsistent naming
   • Deep nesting issues
   • Large array optimization

Example Analysis

CopyJSON Structure Analysis:

Type: Object
Keys: 3 (name, items, metadata)

Schema:
{
  "name": string,
  "items": array[3] of numbers,
  "metadata": {
    "created": string,
    "updated": string
  }
}

Depth: 2 levels
Total size: ~150 bytes

Best Practices

1. Always validate before formatting - Don't format invalid JSON
2. Show clear error messages - Include line numbers and context
3. Preserve data types - Don't convert numbers to strings unnecessarily
4. Handle edge cases - Empty objects, null values, Unicode characters
5. Ask before major changes - e.g., sorting keys, removing comments

Examples

Example 1: Validate and Fix

User request: "Validate this JSON and fix any errors"

Response:

CopyFound 2 issues:

1. Line 3: Trailing comma after "name"
2. Line 5: Single quotes instead of double quotes

Here's the corrected JSON:
{
  "name": "example",
  "data": {
    "value": 42
  }
}

Example 2: Format

User request: "Format this JSON nicely"

Response:

Copy{
  "users": [
    {
      "id": 1,
      "name": "Alice"
    },
    {
      "id": 2,
      "name": "Bob"
    }
  ],
  "total": 2
}

Example 3: Convert to YAML

User request: "Convert this JSON to YAML"

Response:

Copyusers:
  - id: 1
    name: Alice
  - id: 2
    name: Bob
total: 2