pattern-schema_skill

Overview

This skill generates a complete schemas.tsx file that defines all data types and Input/Output interfaces for patterns before any pattern code is written. It enforces the project conventions for Default, Writable, Stream, NAME and UI fields so generated types are testable and compile without TypeScript errors. It is focused on correctness, testability, and adherence to the documented rules.

How this skill works

The skill reads the pattern specification and emits TypeScript interfaces and supporting type imports following the provided template. It wraps editable fields with Writable<>, marks optional-initial values with Default<,>, declares actions as Stream<>, and adds required sub-pattern markers [NAME] and [UI] in Output interfaces. The output file passes the type check command deno task ct check schemas.tsx --no-run when conventions are followed.

When to use it

• Starting a new pattern: generate all types before implementing behavior.
• Refactoring patterns to ensure Input/Output consistency and testability.
• Onboarding or enforcing team-wide schema conventions across patterns.
• Preparing patterns for automated tests that use .send() or Stream linking.

Best practices

• Always use pattern<Input, Output>() — never single-type pattern<State>().
• Wrap every editable field in Input with Writable<> to allow writes.
• Use Default<T, value> for fields that may be undefined initially.
• Declare actions in Output as Stream<T> so they are testable and linkable.
• Include [NAME]: string and [UI]: VNode on Output interfaces for sub-patterns.

Example use cases

• Generate schemas.tsx for a todo item pattern with Item, ItemInput and ItemOutput.
• Create schema for a list-of-items pattern where list and item sub-patterns expose NAME and UI.
• Update an existing pattern to convert mutable fields into Writable<> and mark outputs correctly.
• Produce types that enable unit tests to call .send() against Stream actions.