business-logic-ensure-business-constraints
Ensure Business Constraints for Business Logic
Goal
Write business-logic business constraints with a consistent ensure ... formalism translated into the syntax and naming conventions of the language in use.
Examples of the intended formalism are:
ensure requester is enabledensure there are available cars
Do not copy those phrases verbatim unless the language style truly fits them. Translate them into the local code style, naming style, and control-flow conventions while preserving the same meaning.
These business constraints do not produce business data. They succeed with a unit-equivalent result such as void, unit, undefined, or None, or they fail with an error.
What Counts as In Scope
Apply this skill to code that does one or more of these things:
More from code-sherpas/agent-skills
neverthrow-return-types
Require `neverthrow`-based return types in TypeScript and JavaScript code whenever the surrounding technology allows it. Use when creating, refactoring, reviewing, or extending standalone functions, exported module functions, class methods, object methods, service methods, repository methods, and similar APIs that should expose explicit success and failure result types in their signatures. Prefer `Result<T, E>` for synchronous code and `ResultAsync<T, E>` for asynchronous code. Only skip a `neverthrow` return type when a framework, library, runtime interface, or externally imposed contract is incompatible and requires a different return shape.
19neverthrow-wrap-exceptions
Capture exceptions and promise failures with `neverthrow` instead of hand-written `try/catch` in TypeScript and JavaScript code. Use when wrapping synchronous functions that may throw, promise-returning functions that may throw before returning, existing `PromiseLike` values that may reject, or third-party APIs such as parsers, database clients, HTTP clients, file-system helpers, serializers, and SDK calls. Prefer `Result.fromThrowable` for synchronous throwers, `ResultAsync.fromThrowable` for promise-returning functions that may throw or reject, and `ResultAsync.fromPromise` when you already have a `PromiseLike` value in hand. Only keep `try/catch` when the language construct, cleanup requirement, or framework boundary truly requires it.
14atomic-design
Create or update web UI components with a strict reuse-first workflow. Use when building, refactoring, restyling, or extending frontend or template components while minimizing raw DOM or HTML by reusing or generalizing existing components first.
11write-persistence-representations
Create or update persistence-layer data representations in any stack, including ORM entities, schema definitions, table mappings, document models, collection definitions, and similar database-facing code. Use when agents needs to add or change persisted fields, identifiers, relationships, indexes, timestamps, auditing fields, or storage mappings in frameworks, libraries, or ORMs such as Prisma, TypeORM, Sequelize, Drizzle, Mongoose, Hibernate/JPA, Doctrine, Ecto, Active Record, or equivalent persistence technologies.
8business-logic
Identify, interpret, review, or write business logic in code. Use when an agent needs to decide whether code expresses business rules, business algorithms, or business workflows, or when it must implement, preserve, or refactor code that creates, stores, or transforms data according to real business policies.
8immutable-domain-entities
Require the immutable design pattern for domain entities. Use when an agent needs to create, modify, review, or interpret domain entities and should preserve identity while expressing state changes through new immutable instances. Domain entities must be modeled as immutable classes, not as plain type aliases or interfaces paired with standalone functions.
8