ActiveRecord
This skill should be used when the user asks to "write a migration", "add a column", "add column to table", "create an index", "add a foreign key", "set up associations", "fix N+1 queries", "optimize queries", "add validations", "create callbacks", "use eager loading", or mentions ActiveRecord, belongs_to, has_many, has_one, :through associations, polymorphic associations, inverse_of, touch: true, counter_cache, dependent: destroy, where clauses, scopes, includes, preload, eager_load, joins, find_each, batch processing, counter caches, foreign key constraints, or database constraints. Should also be used when editing *_model.rb files, working in app/models/ directory, db/migrate/, discussing query performance, N+1 prevention, validation vs constraint decisions, or reviewing database schema design.
Draper Decorators
This skill should be used when the user asks to "create a decorator", "write a decorator", "move logic into decorator", "clean logic out of the view", "isn't it decorator logic", "test a decorator", or mentions Draper, keeping views clean, or representation logic in decorators. Should also be used when editing *_decorator.rb files, working in app/decorators/ directory, questioning where formatting methods belong (models vs decorators vs views), or discussing methods like full_name, formatted_*, display_* that don't belong in models. Provides guidance on Draper gem best practices for Rails applications.
MCP Server (Ruby)
This skill should be used when the user asks to "create an MCP server", "build MCP tools", "define MCP prompts", "register MCP resources", "implement Model Context Protocol", or mentions the mcp gem, MCP::Server, MCP::Tool, JSON-RPC transport, stdio transport, or streamable HTTP transport. Should also be used when editing MCP server files, working with tool/prompt/resource definitions, or discussing LLM tool integrations in Ruby.
RSpec Testing
This skill should be used when the user asks to "write specs", "create spec", "add RSpec tests", "fix failing spec", or mentions RSpec, describe blocks, it blocks, expect syntax, test doubles, or matchers. Should also be used when editing *_spec.rb files, working in spec/ directory, planning implementation phases that include tests (TDD/RGRC workflow), writing Testing Strategy or Success Criteria sections, discussing unit or integration tests, or reviewing spec output and test failures. Comprehensive RSpec and FactoryBot reference with best practices, ready-to-use patterns, and examples.