Okyline Skill — Data skill for Claude Code

Okyline Skill for Claude

A skill that turns Claude into an Okyline expert - able to create, edit, and convert [Okyline](https://github.com/Okyline/okyline-spec) schemas, a declarative, example-driven syntax for describing and validating JSON data.

Features

Full Okyline core language support:

• Example-driven: structure and types inferred from realistic example values
• Inline constraints: ranges (0..100), length {2,50}, enums ('A','B','C'), regex ~pattern~, required @, nullable ?...
• Arrays and maps: size [1,10], element validation ->, uniqueness !, pattern keys
• Custom formats $format and nomenclatures $nomenclature
• Built-in formats: $Email, $Date, $DateTime...
• Conditional directives $appliedIf, $requiredIf, $forbiddenIf... and the checks the engine runs when a schema loads
• Expression language for computed validations $compute, exact decimal arithmetic
• Reusable definitions with $defs, &Name references, $ref inclusion, $override / $amend adaptation, $entries validation entry points
• Virtual fields $field for conditions on derived values
• External imports $deps / $import for cross-schema composition

Installation

Claude.ai

1. Go to Settings > Customize > Skills
2. Click + > Create skill and upload the ZIP file

Claude Code

Copy or extract this folder to your skills directory:

# Global (all projects)
~/.claude/skills/okyline/

# Or project-specific
.claude/skills/okyline/

OpenAI Codex CLI

Copy or extract this folder to:

~/.codex/skills/okyline/

Usage

Simply ask Claude to create an Okyline schema:

• "Create an Okyline schema for a user profile"
• "Write an okyline for an invoice with line items"
• "Generate a JSON validation schema using Okyline"

You can also provide more context:

• "Create an Okyline schema for a product with name (required, 2-100 chars), price (positive), and optional description"
• "Convert this JSON Schema